OPPO Find X3 Pro on ColorOS 11.2
Security Target
Version: 1.1
Status: Release
Last Update: 2021-09-27
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Revision History
Revision Date Author(s) Changes to Previous Revision
0.1 2021-03-
09
Di Li First draft of this ST.
0.4 2021-03-
12
Di Li Update according to Yi Cheng’s review comments.
0.5 2021-03-
31
Di Li Update according to Yi Cheng’s review comments.
0.6 2021-04-
10
Di Li Update according to Yi Cheng’s review comments.
0.7 2021-05-
07
Di Li Update according to Yi Cheng’s review comments.
0.8 2021-05-
10
Di Li Update according to Yi Cheng’s review comments.
1.0 2021-06-
22
Di Li Update the build number of the TOE, and editorial changes.
1.1 2021-09-
27
Di Li Update the build number of the TOE to the latest October
build.
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Table of Contents
1 INTRODUCTION.....................................................................................................................7
1.1 SECURITY TARGET IDENTIFICATION ................................................................................................. 7
1.2 TOE IDENTIFICATION .................................................................................................................. 7
1.3 TOE OVERVIEW......................................................................................................................... 8
1.3.1 TOE Type......................................................................................................................... 8
1.3.2 TOE Usage....................................................................................................................... 8
1.3.3 Major Security Features.................................................................................................. 8
1.4 TOE DESCRIPTION...................................................................................................................... 9
1.4.1 Physical Boundaries ........................................................................................................ 9
1.4.2 Logical Boundaries.......................................................................................................... 9
1.4.3 TOE Documentation...................................................................................................... 12
2 CC CONFORMANCE CLAIM ..................................................................................................13
2.1 CONFORMANCE RATIONALE........................................................................................................ 14
3 SECURITY PROBLEM DEFINITION .........................................................................................15
3.1 THREATS................................................................................................................................. 15
3.2 ASSUMPTIONS ......................................................................................................................... 15
3.3 ORGANIZATIONAL SECURITY POLICIES ........................................................................................... 16
4 SECURITY OBJECTIVES .........................................................................................................17
4.1 SECURITY OBJECTIVES FOR THE TOE............................................................................................. 17
4.2 SECURITY OBJECTIVES FOR THE OPERATIONAL ENVIRONMENT............................................................ 18
5 EXTENDED COMPONENTS DEFINITION ................................................................................19
6 SECURITY REQUIREMENTS ..................................................................................................21
6.1 TOE SECURITY FUNCTIONAL REQUIREMENTS ................................................................................. 21
6.1.1 Security Audit (FAU)...................................................................................................... 24
6.1.2 Cryptographic support (FCS)......................................................................................... 27
6.1.3 User data protection (FDP) ........................................................................................... 33
6.1.4 Identification and authentication (FIA)......................................................................... 34
6.1.5 Security management (FMT) ........................................................................................ 39
6.1.6 Protection of the TSF (FPT)............................................................................................ 43
6.1.7 TOE access (FTA)........................................................................................................... 45
6.1.8 Trusted path/channels (FTP)......................................................................................... 45
6.2 TOE SECURITY ASSURANCE REQUIREMENTS .................................................................................. 45
6.2.1 Development (ADV) ...................................................................................................... 46
6.2.2 Guidance documents (AGD).......................................................................................... 47
6.2.3 Life-cycle support (ALC)................................................................................................. 48
6.2.4 Tests (ATE) .................................................................................................................... 49
6.2.5 Vulnerability assessment (AVA).................................................................................... 49
7 TOE SUMMARY SPECIFICATION...........................................................................................50
7.1 SECURITY AUDIT....................................................................................................................... 50
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7.2 CRYPTOGRAPHIC SUPPORT ......................................................................................................... 51
7.3 USER DATA PROTECTION ........................................................................................................... 57
7.4 IDENTIFICATION AND AUTHENTICATION......................................................................................... 61
7.5 SECURITY MANAGEMENT........................................................................................................... 64
7.6 PROTECTION OF THE TSF ........................................................................................................... 64
7.7 TOE ACCESS ........................................................................................................................... 68
7.8 TRUSTED PATH/CHANNELS......................................................................................................... 69
8 TSF INVENTORY...................................................................................................................70
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List of Tables
Table 1: The Detailed Description of Evaluated Devices.................................................... 9
Table 2: TOE Security Functional Components ................................................................ 21
Table 3: Mandatory Auditable Events .............................................................................. 25
Table 4: Security Management Functions........................................................................ 39
Table 5: Security Assurance Requirements ..................................................................... 45
Table 6: Audit Event ........................................................................................................ 50
Table 7: Supported Cryptographic Algorithms ................................................................. 51
Table 8: Asymmetric Key Generation .............................................................................. 52
Table 9: Salt Generation .................................................................................................. 53
Table 10: Cryptographic Algorithms Provided by BoringSSL............................................ 54
Table 11: CAVP Certificates by Application Processor...................................................... 54
Table 12: Function Categories ......................................................................................... 59
Table 13: Power-up Cryptographic Algorithm Known Answer Tests................................. 67
Table 14: TSF name and path .......................................................................................... 70
Table 15: FAR and FRR Testing Rounds ........................................................................... 72
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List of Figures
Figure 1: Password conditioning diagram........................................................................................ 55
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1 Introduction
This document is the Common Criteria (CC) Security Target (ST) for the OPPO Find X3 Pro on
ColorOS 11.2 product to be evaluated as Mobile Devices in exact compliance with:
• The Mobile Device Fundamentals Protection Profile Version 3.1, dated 16 June, 2017
[PP_MD_V3.1]
This section contains the Security Target (ST) and Target of Evaluation (TOE) identifications,
TOE overview, and TOE description.
The Security Target contains the following additional sections:
• Conformance Claims (Section 2)
• Security Problem Definition (Section 3)
• Security Objectives (Section 4)
• Extended Components Definition (Section 5)
• Security Requirements (Section 6)
• TOE Summary Specification (Section 7)
1.1 Security Target Identification
ST Title: OPPO Find X3 Pro on ColorOS 11.2 Security Target
Version: 1.1
Status: Release
Date: 2021-09-27
Sponsor: Guangdong OPPO Mobile Telecommunications Corp., Ltd
Developer: Guangdong OPPO Mobile Telecommunications Corp., Ltd
Keywords: MDFPP31, Common Criteria, mobile device, TLS, HTTPS, Bluetooth, X509 certificate
1.2 TOE Identification
The TOE is OPPO Find X3 Pro on ColorOS 11.2.
The features provided by the TOE is shown below:
Features OPPO Find X3 Pro
Processor Processor: Qualcomm Snapdragon™ 888 up to 2.8 GHz x 1 + +2.4GHz x 3 + 1.8
GHz x 4 Octa-Core
GPU: Adreno™ 660
RAM 12 GB RAM
Storage 256 GB internal memory (non-expandable)
Display AMOLED 6.70", 20.1:9 ratio (3216 x 1440)
Camera Rear Quad Cameras with LED Flash.
MAIN camera:50 MP all pixel omni-directional PDAF f/1.8
Rear Ultra-wide angle camera: 50 MP all pixel omni-directional PDAF f/2.2
Telephoto camera: 13 MP f/2.4, and AF supported
Macro camera: 3 MP f/3.0
Front Cameras with 32 MP Lens f/2.4
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Communications 5G, 4G LTE Network / Mobile Hotspot / Bluetooth 5.0 / Wi-Fi Tethering / NFC / Wi-Fi
Direct / USB and Bluetooth Tethering / Android Beam (NFC) / Media Server / Screen
Sharing (Miracast) / GPS, A-GPS, BeiDou, GLONASS, and QZSS positioning systems
Battery 4500 mAh
Biometric Optical in-display fingerprint readers
1.3 TOE Overview
1.3.1 TOE Type
The TOE Type is personally-owned mobile phone for both personal and enterprise use.
1.3.2 TOE Usage
The TOE is OPPO Find X3 Pro mobile phone running with ColorOS 11.2.
The TOE OS manages the device hardware and provides the technologies with a rich API set required to
implement native applications, it also provides the capability to approve or reject an application based upon
the API access that the application requires (or to grant applications access at runtime).
The TOE provides a built-in Mobile Device Management (MDM) framework API, giving management features
that may be utilized by external MDM solutions (not part of this evaluation), allowing enterprises to use
profiles to control some of the device settings. Security management capabilities are also provided to users
via the user interface of the device and to administrators through the installation of Configuration Profiles
on the device by using MDM solutions.
The TOE provides cryptographic services for the encryption of data-at-rest within the TOE, for secure
communication channels, for protection of Configuration Profiles, and for use by apps. These cryptographic
services can also be used to establish a trusted channel to other IT entities.
User data protection is provided by encrypting all of the user and mobile application data stored in the
user’s data partition, restricting access by apps and by restricting access until the user has been
successfully authenticated.
User identification and authentication is provided by a user defined passphrase (and supplemented by
biometric technologies) where the minimum length of the passphrase, passphrase rules, and the maximum
number of consecutive failed authentication attempts can be configured by an administrator. Any kind of
Smart Lock mechanism shall be disabled in the configuration of the TOE.
The TOE protects itself by having its own code and data protected from unauthorized access (using
hardware provided memory protection features), by encrypting internal user and TOE Security Functionality
(TSF) data using TSF protected keys and encryption/decryption functions, by self-tests, by ensuring the
integrity and authenticity of TSF updates and downloaded apps, and by locking the TOE upon user request
or after a defined time of user inactivity.
1.3.3 Required non-TOE Hardware/Software/Firmware
The TOE consists of its hardware and the ColorOS, other components that running with TOE, e.g. user
application, wireless AP, authentication server for EAP-TLS mutual authentication, MDM client and server,
and mobile data network, are considered as non-TOE components, but they are still required by the TOE to
perform administrative management functions or other operational functions for the end user or the
administrator.
1.3.4 Major Security Features
This section summarizes the security functions provided by the TOE:
• Security Audit
• Cryptographic support
• User data protection
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• Identification and authentication
• Security management
• Protection of the TSF
• TOE access
• Trusted path/channels
1.4 TOE Description
Table 1: The Detailed Description of Evaluated Devices
Device
Name
Model
Number
Chipset
Vendor
CPU
OS
Version
Build
Number
Kernel Version
OPPO Find
X3 Pro
CPH2173 Qualcomm
Snapdragon
888
Octa-core
ColorOS
11.2
CPH2173_1
1_A.21
Android version 11
kernel version 5.4
1.4.1 Physical Boundaries
The TOE’s physical boundary is the physical perimeter of its enclosure. The TOE runs ColorOS as its
operating system on the Qualcomm Snapdragon 888 processor (refer to as Application Processor). 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.
User documentation listed in Section 1.4.3 is also included in the TOE scope.
1.4.2 Logical Boundaries
This section describes the logical security features offered by the TOE listed in Section 1.3.4.
1.4.2.1 Security audit
The TOE implements a security log and logcat that are each stored in a circular memory buffer. An MDM
agent can read/fetch the security logs, can retrieve logcat logs, and then handle appropriately (potentially
storing the log to Flash or transmitting its contents to the MDM server). These log methods meet the logging
requirements outlined by FAU_GEN.1 in MDFPP31.
1.4.2.2 Cryptographic support
The TOE provides cryptographic services with CAVP certified algorithms via the following two cryptographic
modules:
• BoringSSL 65d184c9f337bb7f461060e3808e07164cb0d236 (User Space)
• Application Processor Snapdragon 888 (Kernel space & User Space)
BoringSSL is a fork of OpenSSL which is built into shared libraries of ColorOS. The cryptographic functions
provided by BoringSSL include symmetric key generation, encryption and decryption, asymmetric key
generation and key establishment, cryptographic hashing, and keyed-hash message authentication. The
TOE also provides below functions which are used to implement security protocols and the encryption of
data-at-rest:
• Random number generation
• Data encryption and decryption
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• Signature generation/verification
• Message digest
• Message authentication
• Key generation
• Key wrapping
Application Processor provides a set of FIPS 140-2 certified hardware cryptographic modules, the
cryptographic functions provided by Application Processor include symmetric key generation, encryption
and decryption, cryptographic hashing, and keyed-hash message authentication. The TOE also provides
below functions which are used to implement security protocols and the encryption of data-at-rest:
• Random number generation
• Data encryption and decryption
• Message digest
• Message authentication
• Key generation
• Key derivation
Many of above listed 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 MDFPP31 standards.
1.4.2.3 User data protection
The TOE controls access to system services by hosted applications, including protection of the Trust Anchor
Database. Additionally, User data in files is protected using cryptographic functions, ensuring this data
remains protected even if the device gets lost or is stolen. Data is protected such that only the app that
owns the data can access it. 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.
1.4.2.4 Identification and authentication
Except for answering calls, making emergency calls, using the cameras, using the flashlight, using the quick
settings, and checking notifications, users need to authenticate using a passcode or a biometric
(fingerprint). The user is required to use the passcode authentication mechanism under the following
conditions.
• Turn on or restart the device
• Unlock the device for the first time after reboot
• Update software
• Erase the device
• View or change passcode settings
• Install enterprise profiles
The passcode can be configured for a minimum length, for dedicated passcode policies, and for a maximum
lifetime. When entered, passcodes are obscured and the frequency of entering passcodes is limited as well
as the number of consecutive failed attempts of entering the passcode.
The TOE also enters a locked state after a (configurable) time of user inactivity, and the user is required to
either enter his passcode or use biometric authentication (fingerprint) to unlock the TOE.
External entities connecting to the TOE via a secure protocol (Extensible Authentication Protocol Transport
Layer Security (EAP-TLS), Transport Layer Security (TLS)) can be authenticated using X.509 certificates.
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1.4.2.5 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
1.4.2.6 Protection of the TSF
Some of the functions the TOE implements to protect the TSF and TSF data are as follows:
• Protection of cryptographic keys - they are not accessible or exportable through the use of the
application processor’s hardware.
• Protection of REKs - 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 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 also protects itself from modification by applications as well as to isolate the
address spaces of applications from one another to protect those applications.
• Digital signature protection of the TSF image - all updates to the TSF need to be digitally signed.
• Software/firmware integrity self-test upon start-up - the TOE will not go operational when this test
fails.
• Digital signature verification for apps.
• Access to defined TSF data and TSF services only when the TOE is unlocked.
• The TOE provides its own timing mechanism to ensure that reliable time information is available
(e.g., for log accountability).
1.4.2.7 TOE access
The TSF provides functions to lock the TOE upon request by user or after an administrator configurable time
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.
1.4.2.8 Trusted path/channels
The TOE supports the use of the following cryptographic protocols that define a trusted channel between
itself and another trusted IT product.
• IEEE 802.11-2012
• IEEE 802.11ac-2013 (a.k.a. Wi-Fi 5)
• IEEE 802.11ax (a.k.a. Wi-Fi 6)
• IEEE 802.1X
• EAP-TLS (1.0, 1.1, 1.2)
• TLS (1.2)
• HTTPS
• Bluetooth (5.0)
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1.4.3 TOE Documentation
Reference Document Name Version
[CC_GUIDE] OPPO Find X3 Pro on ColorOS 11.2 Administrator Guidance 1.1
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2 CC Conformance Claim
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 Extended
• Package Claims:
- The ST does not claim conformance to any packages
• PP Claims:
- Exact conformance: Protection Profile for Mobile Device Fundamentals, Version 3.1, 16
June 2017 (MDFPP31)
• Technical Decisions, all applicable technical decisions until 26 March 2021:
TD No. Applied Rationale
TD0174 – MDFPP30 Yes Optional Ciphersuites for TLS
TD0244 – MDFPP31 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 per TD
TD0369 – MDFPP31 Yes LTTCKM present
TD0371 – MDFPP31 No Use Case 2 not selected
TD0413 – MDFPP31 Yes Any allowed PP-Module
TD0426 – MDFPP31 No This TD has been superseded by TD0502
TD0468 – MDFPP31 Yes Impacts assurance activities
TD0502 – MDFPP31 Yes Adds FFC scheme selections to FCS_CKM.1
TD0523 – MDFPP31 Yes
Adds OCSP stapling and OCSP multi-stapling revocation
methods to FIA_X509_EXT.1
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TD0579 - MDFPP31 Yes
Selects “no other auditable events” and “no additional
auditable events” for FAU_GEN.1, items 7 and 8.
2.1 Conformance Rationale
The ST conforms to MDFPP31. The security problem definition, security objectives, and security
requirements have been drawn from the PP.
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3 Security Problem Definition
The security problem definition has been taken from MDFPP31. It is reproduced here for the
convenience of the reader.
3.1 Threats
T.EAVESDROP Network Eavesdropping (PP_MD_V3.1)
An attacker is positioned on a wireless communications channel or elsewhere on the network
infrastructure. Attackers may monitor and gain access to data exchanged between the Mobile
Device and other endpoints.
T.NETWORK Network Attack (PP_MD_V3.1)
An attacker is positioned on a wireless communications channel or elsewhere on the network
infrastructure. Attackers may initiate communications with the Mobile Device or alter
communications between the Mobile Device and other endpoints in order to compromise the
Mobile Device. These attacks include malicious software update of any applications or system
software on the device. These attacks also include malicious web pages or email attachments
which are usually delivered to devices over the network.
T.PHYSICAL Physical Access (PP_MD_V3.1)
An attacker, with physical access, may attempt to access user data on the Mobile Device including
credentials. These physical access threats may involve attacks, which attempt to access the
device through external hardware ports, impersonate the user authentication mechanisms,
through its user interface, and also through direct and possibly destructive access to its storage
media.
Note: Defending against device re-use after physical compromise is out of scope of this ST.
T.FLAWAPP Malicious or Flawed Application (PP_MD_V3.1)
Applications loaded onto the Mobile Device may include malicious or exploitable code. This code
could be included intentionally by its developer or unknowingly by the developer, perhaps as part
of a software library. Malicious apps may attempt to exfiltrate data to which they have access.
They may also conduct attacks against the platform’s system software which will provide them
with additional privileges and the ability to conduct further malicious activities. Malicious
applications may be able to control the device's sensors (GPS, cameras, and microphones) to
gather intelligence about the user's surroundings even when those activities do not involve data
resident or transmitted from the device. Flawed applications may give an attacker access to
perform network-based or physical attacks that otherwise would have been prevented.
T.PERSISTENT Persistent Presence (PP_MD_V3.1)
Persistent presence on a device by an attacker implies that the device has lost integrity and
cannot regain it. The device has likely lost this integrity due to some other threat vector, yet the
continued access by an attacker constitutes an on-going threat in itself. In this case the device
and its data may be controlled by an adversary at least as well as by its legitimate owner.
3.2 Assumptions
A.CONFIG (PP_MD_V3.1)
It is assumed that the TOE’s security functions are configured correctly in a manner to ensure that
the TOE security policies will be enforced on all applicable network traffic flowing among the
attached networks.
A.NOTIFY (PP_MD_V3.1)
It is assumed that the mobile user will immediately notify the administrator if the Mobile Device is
lost or stolen.
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A.PRECAUTION (PP_MD_V3.1)
It is assumed that the mobile user exercises precautions to reduce the risk of loss or theft of the
Mobile Device.
3.3 Organizational Security Policies
There are no OSPs for the Mobile Device.
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4 Security Objectives
The security objectives for the TOE have been taken from MDFPP31. It is reproduced here for the
convenience of the reader. MDFPP31 offers additional information about the identified security
objectives as well as a security objectives rationale, but that has not been reproduced here and MDFPP31
should be consulted if there is interest in that material.
4.1 Security Objectives for the TOE
The security objectives for the Mobile Device are defined as follows. They are reproduced here for the
convenience of the reader.
O.COMMS Protected Communications (PP_MD_V3.1)
To address the network eavesdropping and network attack threats described in section 3.1,
concerning wireless transmission of Enterprise and user data and configuration data between the
TOE and remote network entities, conformant TOEs will use a trusted communication path. The TOE
will be capable of communicating using one (or more) of these standard protocols: IPsec, TLS,
HTTPS, or Bluetooth. The protocols are specified by RFCs that offer a variety of implementation
choices. Requirements have been imposed on some of these choices (particularly those for
cryptographic primitives) to provide interoperability and resistance to cryptographic attack.
While conformant TOEs must support all of the choices specified in the ST, they may support
additional algorithms and protocols. If such additional mechanisms are not evaluated, guidance
must be given to the administrator to make clear the fact that they were not evaluated.
O.STORAGE Protected Storage (PP_MD_V3.1)
To address the issue of loss of confidentiality of user data in the event of loss of a Mobile Device
(T.PHYSICAL), conformant TOEs will use data-at-rest protection. The TOE will be capable of
encrypting data and keys stored on the device and will prevent unauthorized access to encrypted
data.
O.CONFIG Mobile Device Configuration (PP_MD_V3.1)
To ensure a Mobile Device protects user and enterprise data that it may store or process, conformant
TOEs will provide the capability to configure and apply security policies defined by the user and the
Enterprise Administrator. If Enterprise security policies are configured these must be applied in
precedence of user specified security policies.
O.AUTH Authorization and Authentication (PP_MD_V3.1)
To address the issue of loss of confidentiality of user data in the event of loss of a Mobile Device
(T.PHYSICAL), users are required to enter an authentication factor to the device prior to accessing
protected functionality and data. Some non-sensitive functionality (e.g., emergency calling, text
notification) can be accessed prior to entering the authentication factor. The device will
automatically lock following a configured period of inactivity in an attempt to ensure authorization
will be required in the event of the device being lost or stolen.
Authentication of the endpoints of a trusted communication path is required for network access to
ensure attacks are unable to establish unauthorized network connections to undermine the integrity
of the device.
Repeated attempts by a user to authorize to the TSF will be limited or throttled to enforce a delay
between unsuccessful attempts.
O.INTEGRITY Mobile Device Integrity (PP_MD_V3.1)
To ensure the integrity of the Mobile Device is maintained conformant TOEs will perform self-tests
to ensure the integrity of critical functionality, software/firmware and data has been maintained.
The user shall be notified of any failure of these self-tests. (This will protect against the threat
T.PERSISTENT.)
To address the issue of an application containing malicious or flawed code (T.FLAWAPP), the integrity
of downloaded updates to software/firmware will be verified prior to installation/execution of the
object on the Mobile Device. In addition, the TOE will restrict applications to only have access to the
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system services and data they are permitted to interact with. The TOE will further protect against
malicious applications from gaining access to data they are not authorized to access by randomizing
the memory layout.
O.PRIVACY End User Privacy and Device Functionality (PP_MD_V3.1)
In a BYOD environment (use cases 3 and 4), a personally-owned mobile device is used for both
personal activities and enterprise data. Enterprise management solutions may have the technical
capability to monitor and enforce security policies on the device. However, the privacy of the
personal activities and data must be ensured. In addition, since there are limited controls that the
enterprise can enforce on the personal side, separation of personal and enterprise data is needed.
This will protect against the T.FLAWAPP and T.PERSISTENT threats.
4.2 Security Objectives for the Operational Environment
OE.CONFIG (PP_MD_V3.1)
TOE administrators will configure the Mobile Device security functions correctly to create the
intended security policy.
OE.NOTIFY (PP_MD_V3.1)
The Mobile User will immediately notify the administrator if the Mobile Device is lost or stolen.
OE.PRECAUTION (PP_MD_V3.1)
The Mobile User exercises precautions to reduce the risk of loss or theft of the Mobile Device.
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5 Extended Components Definition
All of the extended requirements in this ST have been drawn from MDFPP31. MDFPP31
defines the following extended requirements and, since they are not redefined in this ST,
MDFPP31 should be consulted for more information in regard to those CC extensions.
Extended SFRs:
• FCS_CKM_EXT.1: Extended: Cryptographic Key Support
• FCS_CKM_EXT.2: Extended: Cryptographic Key Random Generation
• FCS_CKM_EXT.3: Extended: Cryptographic Key Generation
• FCS_CKM_EXT.4: Extended: Key Destruction
• FCS_CKM_EXT.5: Extended: TSF Wipe
• FCS_CKM_EXT.6: Extended: Salt Generation
• FCS_HTTPS_EXT.1: Extended: HTTPS Protocol
• FCS_IV_EXT.1: Extended: Initialization Vector Generation
• FCS_RBG_EXT.1: Extended: Cryptographic Operation (Random Bit Generation)
• FCS_SRV_EXT.1: Extended: Cryptographic Algorithm Services
• FCS_STG_EXT.1: Extended: Cryptographic Key Storage
• FCS_STG_EXT.2: Extended: Encrypted Cryptographic Key Storage
• FCS_STG_EXT.3: Extended: Integrity of encrypted key storage
• FCS_TLSC_EXT.1: Extended: TLS Protocol
• FCS_TLSC_EXT.2: Extended: TLS 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
• FIA_BLT_EXT.4: Extended: Secure Simple Pairing
• FIA_BMG_EXT.1: Extended: Accuracy of Biometric 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
20
• FIA_X509_EXT.1: Extended: Validation of certificates
• FIA_X509_EXT.2: Extended: X509 certificate authentication
• FIA_X509_EXT.3: Extended: Request Validation of certificates
• FMT_MOF_EXT.1: Extended: Management of security functions behavior
• FMT_SMF_EXT.1: Extended: Specification of Management Functions
• FMT_SMF_EXT.2: Extended: Specification of Remediation Actions
• FPT_AEX_EXT.1: Extended: Anti-Exploitation Services (ASLR)
• FPT_AEX_EXT.2: Extended: Anti-Exploitation Services (Memory Page Permissions)
• FPT_AEX_EXT.3: Extended: Anti-Exploitation Services (Overflow Protection)
• FPT_AEX_EXT.4: Extended: Domain Isolation
• FPT_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.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
• FTP_ITC_EXT.1: Extended: Trusted channel Communication
Extended SARs:
• ALC_TSU_EXT.1: Timely Security Updates
21
6 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 MDFPP31. The refinements and operations already performed in
MDFPP31 are not identified (e.g., highlighted) here, rather the requirements have been copied from
MDFPP31 and any residual operations have been completed herein. Of particular note, MDFPP31 made
a number of refinements and completed some of the SFR operations defined in the Common Criteria
(CC) and that MDFPP31 should be consulted to identify those changes if necessary.
The SARs are also drawn from MDFPP31 which includes all the SARs for EAL 1 augmented with
ALC_TSU_EXT.1. However, the SARs are effectively refined since requirement-specific 'Assurance
Activities' are defined in MDFPP31 that serve to ensure corresponding evaluations will yield more
practical and consistent assurance than the EAL 1 assurance requirements alone. MDFPP31 should be
consulted for the assurance activity definitions.
Conventions
The following conventions have been applied in this document:
• Security Functional Requirements – Part 1 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.
Iteration is indicated by a number in parentheses after the SFR name. For example,
FIA_UAU.6(1) and FIA_UAU.6(2) indicate that the ST includes two iterations of the
FIA_UAU.6 requirement, (1) and (2).
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 (e.g., “… all objects”), and strikethrough for deletions (e.g., “… some legacy
protocol …”).
6.1 TOE Security Functional Requirements
The following table identifies the SFRs that are implemented by TOE.
Table 2: TOE Security Functional Components
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.2(1): Cryptographic key establishment
FCS_CKM.2(2): Cryptographic key establishment (while device is
locked)
22
FCS_CKM_EXT.1: Extended: Cryptographic Key Support
FCS_CKM_EXT.2: Extended: Cryptographic Key Random
Generation
FCS_CKM_EXT.3: Extended: Cryptographic Key Generation
FCS_CKM_EXT.4: Extended: Key Destruction
FCS_CKM_EXT.5: Extended: TSF Wipe
FCS_CKM_EXT.6: Extended: Salt Generation
FCS_COP.1(1): Cryptographic operation
FCS_COP.1(2): Cryptographic operation
FCS_COP.1(3): Cryptographic operation
FCS_COP.1(4): Cryptographic operation
FCS_COP.1(5): Cryptographic operation
FCS_HTTPS_EXT.1: Extended: HTTPS Protocol
FCS_IV_EXT.1: Extended: Initialization Vector Generation
FCS_RBG_EXT.1: Extended: Cryptographic Operation (Random
Bit Generation)
FCS_SRV_EXT.1: Extended: Cryptographic Algorithm Services
FCS_STG_EXT.1: Extended: Cryptographic Key Storage
FCS_STG_EXT.2: Extended: Encrypted Cryptographic Key
Storage
FCS_STG_EXT.3: Extended: Integrity of encrypted key storage
FCS_TLSC_EXT.1: Extended: TLS Protocol
FCS_TLSC_EXT.2: Extended: TLS 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
23
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_BMG_EXT.1: Extended: Accuracy of Biometric
Authentication
FIA_PMG_EXT.1: Extended: Password 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.3: Extended: Request Validation of certificates
FMT: Security management
FMT_MOF_EXT.1: Extended: Management of security functions
behavior
FMT_SMF_EXT.1: Extended: Specification of Management
Functions
FMT_SMF_EXT.2: Extended: Specification of Remediation
Actions
FPT: Protection of the TSF
FPT_AEX_EXT.1: Extended: Anti-Exploitation Services (ASLR)
FPT_AEX_EXT.2: Extended: Anti-Exploitation Services (Memory
Page Permissions)
24
FPT_AEX_EXT.3: Extended: Anti-Exploitation Services (Overflow
Protection)
FPT_AEX_EXT.4: Extended: Domain Isolation
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.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
FTP: Trusted path/channels FTP_ITC_EXT.1: Extended: Trusted channel Communication
6.1.1 Security Audit (FAU)
6.1.1.1 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 3
7. [no additional auditable events]
8. [no additional auditable events] (TD0579 applied)
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
25
4. The outcome (success or failure) of the event
5. Additional information in Table 3
6. [no additional information]
Table 3: Mandatory Auditable Events
Requirement Auditable Events
Additional Audit Record
Contents
FAU_GEN.1 None.
FAU_STG.1 None.
FAU_STG.4 None.
FCS_CKM_EXT.1 [None]. No additional information.
FCS_CKM_EXT.2 None.
FCS_CKM_EXT.3 None.
FCS_CKM_EXT.4 None.
FCS_CKM_EXT.5 [None]. No additional information.
FCS_CKM_EXT.6 None.
FCS_CKM.1 [None]. No additional information.
FCS_CKM.2(*) None.
FCS_COP.1(*) None.
FCS_IV_EXT.1 None.
FCS_SRV_EXT.1 None.
FCS_STG_EXT.1
Import or destruction of key.
Identity of key. Role and
identity of requestor.
[No other events]
FCS_STG_EXT.2 None.
FCS_STG_EXT.3
Failure to verify integrity of
stored key.
Identity of key being verified.
FDP_DAR_EXT.1 [None]. No additional information.
FDP_DAR_EXT.2 Failure to encrypt/decrypt data. No additional information
FDP_IFC_EXT.1 None.
FDP_STG_EXT.1
Addition or removal of
certificate from Trust Anchor
Database.
Subject name of certificate.
26
FIA_PMG_EXT.1 None.
FIA_TRT_EXT.1 None.
FIA_UAU_EXT.1 None.
FIA_UAU.5 None.
FIA_UAU.7 None.
FIA_X509_EXT.1
Failure to validate X.509v3
certificate.
Reason for failure of validation.
FMT_MOF_EXT.1 None.
FPT_AEX_EXT.1 None.
FPT_AEX_EXT.2 None.
FPT_AEX_EXT.3 None.
FPT_JTA_EXT.1 None.
FPT_KST_EXT.1 None.
FPT_KST_EXT.2 None.
FPT_KST_EXT.3 None.
FPT_NOT_EXT.1 [None]. [No additional information].
FPT_STM.1 None.
FPT_TST_EXT.1
Initiation of self-test.
Failure of self-test. [None]
FPT_TST_EXT.2(1)
Start-up of TOE. No additional information.
[None] [No additional information]
FPT_TUD_EXT.1 None.
FTA_SSL_EXT.1 None.
6.1.1.2 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.
27
6.1.1.3 Prevention of Audit Data Loss (FAU_STG.4)
FAU_STG.4.1
The TSF shall overwrite the oldest stored audit records if the audit trail is full.
6.1.2 Cryptographic support (FCS)
6.1.2.1 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 [
o “NIST curves” P-384 and [P-256] that meet the following: FIPS
PUB 186-4, “Digital Signature Standard (DSS)”, Appendix B.4],
]. (TD0502 applied)
Application note: TD0502: Cryptographic selections and updates for MDF PP. FCS_CKM.1 and
FCS_CKM.2 in the MDF PP do not include/specify appropriate selections for key agreement groups and
do not support safe primes.
6.1.2.2 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 [
o NIST Special Publication 800-56B, 'Recommendation for Pair-Wise
Key Establishment Schemes Using Integer Factorization
Cryptography']
- Elliptic curve-based key establishment schemes that meets the following:
NIST Special Publication 800-56A, 'Recommendation for Pair-Wise Key
Establishment Schemes Using Discrete Logarithm Cryptography'
]. (TD0502 applied)
Application note: TD0502: Cryptographic selections and updates for MDF PP. FCS_CKM.1 and
FCS_CKM.2 in the MDF PP do not include/specify appropriate selections for key agreement groups and
do not support safe primes.
6.1.2.3 Cryptographic key establishment (while device is locked)
(FCS_CKM.2(2))
FCS_CKM.2.1(2)
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.
28
6.1.2.4 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].
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.
6.1.2.5 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)
Application note: TD0351: Additional methods for DEK formation. The methods that MDFPP31 allows
for KEK formation should be expanded to DEKs.
6.1.2.6 Extended: Cryptographic Key Generation
(FCS_CKM_EXT.3)
FCS_CKM_EXT.3.1
The TSF shall use [
- asymmetric KEKs of [112 bits] 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 using 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 [concatenating the keys and using a KDF (as
described in SP 800-108), encrypting one key with another]
].
Application note: TD0366: Flexibility in Password Conditioning in FCS_COP.1(5). With impact on
FCS_CKM_EXT.3.2.
6.1.2.7 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
o For volatile memory, the destruction shall be executed by a single direct
overwrite [consisting of zeroes].
29
o For non-volatile EEPROM, the destruction shall be executed by a single
direct overwrite consisting of a pseudo random pattern using the TSF's
RBG (as specified in FCS_RBG_EXT.1), followed a read-verify.
o For non-volatile flash memory, that is not wear-leveled1, the destruction
shall be executed [by a block erase that erases the reference to
memory that stores data as well as the data itself].
o For non-volatile flash memory, that is wear-leveled, the destruction shall
be executed [by a block erase].
o 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.
6.1.2.8 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 the KEKs in non-
volatile memory by following the requirements in FCS_CKM_EXT.4.1,
- Overwriting all Protected Data according to the following rules:
o 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 a read-verify.
o 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].
o For flash memory, that is wear-leveled, the destruction shall be
executed [by a block erase].
o 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.
6.1.2.9 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.
6.1.2.10 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
• [
o AES Key Wrap (KW) (as defined in NIST SP 800-38F),
o AES-GCM (as defined in NIST SP 800-38D),
1 Wear-leveling phrase and next bullet added by TD0047 and selection modified by TD0057.
30
o AES-XTS (as defined in NIST SP 800-38E) mode
]
and cryptographic key sizes 128-bit key sizes and [256-bit key sizes].
6.1.2.11 Cryptographic operation (FCS_COP.1(2))
FCS_COP.1.1(2)
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 bits] that meet the following: FIPS Pub 180-4.
6.1.2.12 Cryptographic operation (FCS_COP.1(3))
FCS_COP.1.1(3)
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
• [
o ECDSA schemes using “NIST curve” P-384 and [P-256] that meet
the following: FIPS PUB 186-4, 'Digital Signature Standard (DSS)',
Section 5,
].
6.1.2.13 Cryptographic operation (FCS_COP.1(4))
FCS_COP.1.1(4)
The TSF shall perform keyed-hash message authentication in accordance with a
specified cryptographic algorithm HMAC-SHA-1 and [HMAC-SHA-256, HMAC-SHA-
384, HMAC-SHA-512] and cryptographic key sizes [160, 256, 384, 512 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”.
6.1.2.14 Cryptographic operation (FCS_COP.1(5))
FCS_COP.1.1(5)
The TSF shall perform conditioning in accordance with a specified cryptographic
algorithm HMAC-[SHA-256] using a salt, and [key stretching with scrypt] and
output cryptographic key sizes [256] that meet the following: NIST [no standard].
(TD0366 applied)
Application note: TD0366: Flexibility in Password Conditioning in FCS_COP.1(5).
6.1.2.15 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.
6.1.2.16 Extended: Initialization Vector Generation (FCS_IV_EXT.1)
FCS_IV_EXT.1.1
The TSF shall generate IVs in accordance with Table 11 in MDFPP31: References and IV
Requirements for NIST-approved Cipher Modes.
31
6.1.2.17 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 [Hash_DRBG (any), CTR_DRBG (AES)].
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.
6.1.2.18 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(3)
- All mandatory and selected algorithms in FCS_COP.1(2)
- All mandatory and selected algorithms in FCS_COP.1(4)
[
- All mandatory and [selected algorithms] in FCS_CKM.1,
].
6.1.2.19 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].
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, the administrator].
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
[the administrator, 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 [the
administrator, a common application developer].
32
6.1.2.20 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 [
o Protected by the REK with [
o encryption by a KEK chaining from a REK,
o encryption by a KEK that is derived from a REK],
],
o Protected by the REK and the password with [
o encryption by a KEK chaining to a REK and the password-
derived or biometric-unlocked KEK
o 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, CBC mode]
].
Application note: TD0369: Long-term trusted channel key material. Changes to the PP application
notes.
6.1.2.21 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 [ [WPA2 WiFi
PSK, Bluetooth Keys], all software-based key storage] by [
• [GCM] cipher mode for encryption according to FCS_STG_EXT.2,
• a keyed hash (FCS_COP.1(4)) using a key protected by a key protected by
FCS_STG_EXT.2
]. (TD0369 applied)
FCS_STG_EXT.3.2
The TSF shall verify the integrity of the [MAC] of the stored key prior to use of the key.
Application note: TD0369: Long-term trusted channel key material. Changes to the PP application
notes.
6.1.2.22 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: [
- Optional Ciphersuites: [
o TLS_RSA_WITH_AES_256_GCM_SHA384 as defined in RFC 5288,
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_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.
33
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.
Application note: TD0174: The “TLS_RSA_WITH_AES_128_CBC_SHA256 as defined in RFC5246” and
“TLS_RSA_WITH_AES_256_CBC_SHA256 as defined in RFC5246” ciphersuites have been moved from
the mandatory ciphersuites to the optional one.
6.1.2.23 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)
Application note: TD0244: FCS_TLSC_EXT - TLS Client Curves Allowed. FCS_TLSC_EXT.2 in MD PP
v3.1 limits the curves that a client may propose.
6.1.3 User data protection (FDP)
6.1.3.1 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 [application, groups of
applications] from accessing [all] data stored by other [application, groups of
applications]. Exceptions may only be explicitly authorized for such sharing by [a
common application developer (for sharing between applications), no one
(for sharing between personal and enterprise profiles)].
6.1.3.2 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 (for address book), no one (for calendar, keychain)].
6.1.3.3 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.
6.1.3.4 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
34
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.
6.1.3.5 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.
6.1.3.6 Extended: Storage of Critical Biometric Parameters
(FDP_PBA_EXT.1)
FDP_PBA_EXT.1.1
The TSF shall protect the authentication template [using a password as an
additional factor].
6.1.3.7 Extended: User Data Storage (FDP_STG_EXT.1)
FDP_STG_EXT.1.1
The TSF shall provide protected storage for the Trust Anchor Database.
6.1.3.8 Extended: Inter-TSF user data transfer protection
(FDP_UPC_EXT.1)
FDP_UPC_EXT.1.1
The TSF provide a means for non-TSF applications executing on the TOE to use TLS,
HTTPS, Bluetooth BR/EDR, and [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
The TSF shall permit the non-TSF applications to initiate communication via the trusted
channel.
6.1.4 Identification and authentication (FIA)
6.1.4.1 Authentication failure handling (FIA_AFL_EXT.1)
FIA_AFL_EXT.1.1
The TSF shall consider password and [no other] as critical authentication
mechanisms.
FIA_AFL_EXT.1.2
The TSF shall detect when a configurable positive integer within [0 - 50] of [non-
unique] unsuccessful authentication attempts occur related to last successful
authentication for each authentication mechanism.
35
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.
6.1.4.2 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.
6.1.4.3 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.
6.1.4.4 Extended: Rejection of Duplicate Bluetooth Connections
(FIA_BLT_EXT.3)
FIA_BLT_EXT.3.1
The TSF shall discard pairing and session initialization attempts from a Bluetooth
device address (BD_ADDR) to which an active session already exists. (TD0468 applied)
6.1.4.5 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.
6.1.4.6 Extended: Accuracy of Biometric Authentication
(FIA_BMG_EXT.1(1))
FIA_BMG_EXT.1.1(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(1)
The overall System Authentication False Accept Rate (SAFAR) shall be no greater than
1 in [1:5,000] within a 1% margin.
36
Application note: TD0301: Updates to Administrator Management and Biometric Authentication. For
FIA_BMG_EXT.1.1, vendors should be allowed to assign their particular FAR as opposed to being forced
to select one from the list.
6.1.4.7 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.
6.1.4.8 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.
6.1.4.9 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: - unlock the user's Credential encrypted (CE files) and keystore keys
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.”
].
6.1.4.10 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
37
6.1.4.11 Re-Authentication (FIA_UAU.6(2))
FIA_UAU.6.1(2)
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].
6.1.4.12 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.
6.1.4.13 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.
6.1.4.14 Extended: Timing of Authentication (FIA_UAU_EXT.2)
FIA_UAU_EXT.2.1
The TSF shall allow [[
- Take screen shots (stored internally)
- Enter password to unlock
- Make/receive emergency calls
- Take pictures (stored internally) - unless the camera was disabled
- Turn the TOE off
- Restart the TOE
- Enable Airplane mode
- See notifications (note that some notifications identify actions, for example
to view a screenshot; however, selecting those notifications highlights the
password prompt and require the password to access that data)
- Configure sound, vibrate, or mute
- Set the volume (up and down) for ringtone
- Access notification widgets (without authentication):
o Flashlight toggle
o Do not disturb toggle
o Auto rotate toggle
o Sound (on, mute, vibrate)
o Night light filter toggle
]] 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.
38
6.1.4.15 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, that the CA flag is set to TRUE for all CA certificates, and
that any path constraints are met.
- The TSF shall validate that any CA certificate includes a caSigning purpose in the key
usage field.
- The TSF shall validate the revocation status of the certificate using [OCSP as
specified in RFC 2560].
- The TSF shall validate the extendedKeyUsage field according to the following rules:
o Certificates used for trusted updates and executable code integrity
verification shall have the Code Signing purpose (id-kp 3 with OID
1.3.6.1.5.5.7.3.3) in the extendedKeyUsage field.
o Server certificates presented for TLS shall have the Server Authentication
purpose (id-kp 1 with OID 1.3.6.1.5.5.7.3.1) in the extendedKeyUsage
field.
o 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
EKU field. [conditional]
o Client certificate presented for TLS shall have the Client Authentication
purpose (id-kp 2 with OID 1.3.6.1.5.5.7.3.2) in the EKU field.
o OCSP certificates presented for OCSP responses shall have the OCSP
Signing purpose (id-kp 9 with 1.3.6.1.5.5.7.3.9) in the EKU field.
[conditional]
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.
(TD0523 applied)
Application note: TD0523: Updates to Certificate Revocation (FIA_X509_EXT.1). Two items are
addressed via this TD, revocation checking and validation of ECC certificates.
6.1.4.16 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, 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].
6.1.4.17 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.
39
6.1.5 Security management (FMT)
6.1.5.1 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 4 to the
user.
FMT_MOF_EXT.1.2
The TSF shall restrict the ability to perform the functions in column 5 of Table 4 to the
administrator when the device is enrolled and according to the administrator-
configured policy.
6.1.5.2 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 4 Security
Management Functions.
Table 4: Security Management Functions
Management Function
Status Markers:
M – Mandatory
I – Implemented optional function
FMT_SMF_EXT.1
Users
(exclusive)
Administrator
MDM
Policy
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
[d. 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
40
4. enable/disable [Bluetooth,
NFC, Wi-Fi, cellular (GSM/WCDMA/LTE TDD/
LTE FDD/5G NR)]
The administrator can disable the Bluetooth using the TOE’s MDM
APIs. Once disabled, a user cannot enable the Bluetooth.
The administrator cannot fully disable/restrict NFC, Wi-Fi or cellular
voice capabilities.
The TOE’s radios operate at frequencies of 13.56 MHz (NFC), 2.4 GHz
(Bluetooth), 2.4/5 GHz (Wi-Fi), 850/900/1800/1900MHz (GSM), Bands
1/2/4/5/6/8/19 (WCDMA), Bands 34/38/39/40/41/42 (TDD-LTE), Bands
1/2/3/4/5/7/8/12/13/17/18/19/20/25/26/28/32/66 (LTE FDD),
n1/n3/n5/n7/n8/n20/n28/n38/n40/n41/n77/n78/n79 (5G NR).
M
M I
I I
5. enable/disable [microphone, camera]:
a. across device (microphone, camera),
[b. on a per-app basis (microphone, camera)]
An administrator can enable/disable the device’s microphone and
camera via an MDM API. Once the microphone or camera 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 MDM
M M
41
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 [Biometric Authentication Factor]
The Biometric Authentication Factor is always enabled and could not
be disabled by user.
I I I
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
I I I
42
disable Developer Mode.
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
The administrator could read logs that kept by the TSF using
"TestDPC -> Request security logs", and user could read logs via
“LogKit” tool.
I I
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,
]
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]
43. place applications into application process groups based on
[assignment: enterprise configuration settings]
44. Unenroll the TOE from management I I I
45. Enable/disable the Always On VPN protection
Administrator could config Always On VPN protection by
using DevicePolicyManage`s API setAlwaysOnVpnPackage.
Or the user can access this by going to “Settings” ->
“Connection & sharing” -> “VPN”
46. Revoke Biometric template
47. [assignment: list of other management functions to be
provided by the TSF]
6.1.5.3 Extended: Specification of Remediation Actions
(FMT_SMF_EXT.2)
FMT_SMF_EXT.2.1
43
The TSF shall offer [wipe of protected data, wipe of sensitive data, remove
Enterprise applications, remove all device-stored Enterprise resource data]
upon unenrollment and [factory reset]. (TD0346 applied)
Application note: TD0346: Revision of FMT_SMF_EXT.2 in MDF PP. Remove "alert the administrator"
from the selection.
6.1.6 Protection of the TSF (FPT)
6.1.6.1 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.
6.1.6.2 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.
6.1.6.3 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.
6.1.6.4 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.
6.1.6.5 Extended: JTAG Disablement (FPT_JTA_EXT.1)
FPT_JTA_EXT.1.1
The TSF shall [control access by a signing key] to JTAG.
6.1.6.6 Extended: Key Storage (FPT_KST_EXT.1)
FPT_KST_EXT.1.1
The TSF shall not store any plaintext key material in readable non-volatile memory.
6.1.6.7 Extended: No Key Transmission (FPT_KST_EXT.2)
FPT_KST_EXT.2.1
The TSF shall not transmit any plaintext key material outside the security boundary of
the TOE.
44
6.1.6.8 Extended: No Plaintext Key Export (FPT_KST_EXT.3)
FPT_KST_EXT.3.1
The TSF shall ensure it is not possible for the TOE user(s) to export plaintext keys.
6.1.6.9 Extended: Self-Test Notification (FPT_NOT_EXT.1)
FPT_NOT_EXT.1.1
The TSF shall transition to non-operational mode and [no other actions] when the
following types of failures occur:
- failures of the self-test(s)
- TSF software integrity verification failures
- [no other failures]
6.1.6.10 Reliable time stamps (FPT_STM.1)
FPT_STM.1.1
The TSF shall be able to provide reliable time stamps for its own use.
6.1.6.11 Extended: TSF Cryptographic Functionality Testing
(FPT_TST_EXT.1)
FPT_TST_EXT.1.1
The TSF shall run a suite of self-tests during initial start-up (on power on) to
demonstrate the correct operation of all cryptographic functionality.
6.1.6.12 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].
6.1.6.13 Extended: Trusted Update: TSF version query
(FPT_TUD_EXT.1)
FPT_TUD_EXT.1.1
The TSF shall provide authorized users the ability to query the current version of the
TOE firmware/software.
FPT_TUD_EXT.1.2
The TSF shall provide authorized users the ability to query the current version of the
hardware model of the device.
FPT_TUD_EXT.1.3
The TSF shall provide authorized users the ability to query the current version of
installed mobile applications.
6.1.6.14 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 [never update] the TSF boot integrity [hash].
45
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.
6.1.7 TOE access (FTA)
6.1.7.1 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) [no other actions].
6.1.8 Trusted path/channels (FTP)
6.1.8.1 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 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].
6.2 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.
Table 5: Security Assurance Requirements
Requirement Class Requirement Component
Security Target (ASE)
ASE_CCL.1: Conformance claims
ASE_ECD.1: Extended components definition
ASE_INT.1: ST introduction
46
ASE_OBJ.1: Security objectives for the operational environment
ASE_REQ.1: Stated security requirements
ASE_SPD.1: Security Problem Definition
ASE_TSS.1: TOE summary specification
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
6.2.1 Development (ADV)
6.2.1.1 Basic functional specification (ADV_FSP.1)
ADV_FSP.1.1d
The developer shall provide a functional specification.
ADV_FSP.1.2d
The developer shall provide a tracing from the functional specification to the SFRs.
ADV_FSP.1.1c
The functional specification shall describe the purpose and method of use for each
SFR-enforcing and SFR-supporting TSFI.
ADV_FSP.1.2c
The functional specification shall identify all parameters associated with each SFR-
enforcing and SFR-supporting TSFI.
ADV_FSP.1.3c
The functional specification shall provide rationale for the implicit categorisation of
interfaces as SFR-non-interfering.
ADV_FSP.1.4c
The tracing shall demonstrate that the SFRs trace to TSFIs in the functional
specification.
ADV_FSP.1.1e
The evaluator shall confirm that the information provided meets all requirements for
content and presentation of evidence.
ADV_FSP.1.2e
The evaluator shall determine that the functional specification is an accurate and
complete instantiation of the SFRs.
47
6.2.2 Guidance documents (AGD)
6.2.2.1 Operational user guidance (AGD_OPE.1)
AGD_OPE.1.1d
The developer shall provide operational user guidance.
AGD_OPE.1.1c
The operational user guidance shall describe, for each user role, the user-accessible
functions and privileges that should be controlled in a secure processing environment,
including appropriate warnings.
AGD_OPE.1.2c
The operational user guidance shall describe, for each user role, how to use the
available interfaces provided by the TOE in a secure manner.
AGD_OPE.1.3c
The operational user guidance shall describe, for each user role, the available
functions and interfaces, in particular all security parameters under the control of the
user, indicating secure values as appropriate.
AGD_OPE.1.4c
The operational user guidance shall, for each user role, clearly present each type of
security-relevant event relative to the user-accessible functions that need to be
performed, including changing the security characteristics of entities under the control
of the TSF.
AGD_OPE.1.5c
The operational user guidance shall identify all possible modes of operation of the TOE
(including operation following failure or operational error), their consequences and
implications for maintaining secure operation.
AGD_OPE.1.6c
The operational user guidance shall, for each user role, describe the security measures
to be followed in order to fulfil the security objectives for the operational environment
as described in the ST.
AGD_OPE.1.7c
The operational user guidance shall be clear and reasonable.
AGD_OPE.1.1e
The evaluator shall confirm that the information provided meets all requirements for
content and presentation of evidence.
6.2.2.2 Preparative procedures (AGD_PRE.1)
AGD_PRE.1.1d
The developer shall provide the TOE including its preparative procedures.
AGD_PRE.1.1c
The preparative procedures shall describe all the steps necessary for secure
acceptance of the delivered TOE in accordance with the developer's delivery
procedures.
AGD_PRE.1.2c
The preparative procedures shall describe all the steps necessary for secure
installation of the TOE and for the secure preparation of the operational environment in
accordance with the security objectives for the operational environment as described
in the ST.
AGD_PRE.1.1e
The evaluator shall confirm that the information provided meets all requirements for
content and presentation of evidence.
48
AGD_PRE.1.2e
The evaluator shall apply the preparative procedures to confirm that the TOE can be
prepared securely for operation.
6.2.3 Life-cycle support (ALC)
6.2.3.1 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.
6.2.3.2 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.
6.2.3.3 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
The evaluator shall confirm that the information provided meets all requirements for
content and presentation of evidence.
49
6.2.4 Tests (ATE)
6.2.4.1 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.
6.2.5 Vulnerability assessment (AVA)
6.2.5.1 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.
50
7 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
7.1 Security Audit
FAU_GEN.1:
The TOE uses different forms of logs to meet all the required management logging events specified in
Table 1 of the MDFPP31:
1. Security Logs
2. Logcat Logs
Each of the above logging methods are described below.
• Security Logs: A table that depicts the list of all auditable events (for MDFPP31) 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. These logs can be read by an administrator via an MDM agent.
• 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 are
descriptive and do not require the administrator to know the template of the log to understand
its values. Logcat Logs cannot be exported but can be viewed by an administrator via an MDM
agent.
Both types of logs, when full, wrap around and overwrite the oldest log (as the start of the buffer).
The following table enumerates the events that the TOE audits.
Table 6: Audit Event
Requirement Audit Event Content
FAU_GEN.1
Start-up and shutdown of the audit
functions
FAU_GEN.1 All administrative actions
FAU_GEN.1 Start-up and shutdown of the Rich OS
FAU_GEN.1 Insertion or removal of removable media
FAU_GEN.1 [None]
51
FCS_CKM_EXT.1 [None] No additional information.
FCS_CKM_EXT.5 [None] No additional information.
FCS_CKM.1 [None] No additional information.
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.
FDP_DAR_EXT.1 [None.] No additional information.
FDP_DAR_EXT.2 Failure to encrypt/decrypt data. No additional information.
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_NOT_EXT.1 [None] No additional information.
FPT_TST_EXT.1
Initiation of self-test.
Failure of self-test.
No additional information.
FPT_TST_EXT.2(1) Start-up of TOE. No additional information.
FAU_STG.1: For security logs, the TOE stores all audit records in memory, making it only accessible to
the logd daemon, and only applications that are set with the “device owners” permission by MDM 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.
The TOE stores Logcat Logs in memory and only allows access by an administrator via an MDM Agent.
The TOE prevents deleted of these logs by any method other than USB debugging (and enabling USB
Debugging takes the phone out of the evaluated configuration).
FAU_STG.4: The security logs and logcat logs are stored in memory in a circular log buffer of
4096KB/256KB, respectively. Logcat logs alone have a configurable size, able to be set by an MDM API.
There is no limit to the size that the Logcat log buffer can be configured to and it is limited to the size
of the system’s memory. Each log system retains its own circular buffer. Once either log is full, it begins
overwriting the oldest message in its respective buffer and continues overwriting the oldest message
with each new auditable event. These logs persist until they are either overwritten or the device is
restarted.
7.2 Cryptographic Support
The TOE implements cryptographic algorithms in accordance with the following NIST standards.
Table 7: Supported Cryptographic Algorithms
Algorithm NIST Standard SFR Reference
AES CBC, CCMP, KW, KWP,
GCM, CCM, XTS
FIPS 197, SP 800-38A/C/D/E/F FCS_COP.1(1)
52
SHA-1, SHA-256, SHA384,
SHA512
FIPS 180-4 FCS_COP.1(2)
RSA, ECDSA FIPS SP 186-4
FCS_COP.1(3)
FCS_CKM.1
HMAC-SHA-1, HMAC-SHA-256,
HMAC-SHA-384, HMAC-SHA-512
FIPS 198-1 & 180-4 FCS_COP.1(4)
RSA, ECDSA SP800-56A/B
FCS_CKM.2(1)
FCS_CKM.2(2)
DRBG FIPS SP 800-90A FCS_RBG_EXT.1
The Cryptographic support function in the TOE is designed to fulfill the following security functional
requirements:
l FCS_CKM.1: The TOE provides generation of asymmetric keys including:
Table 8: Asymmetric Key Generation
Algorithm Key Sizes / Curves 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 (not domain
parameters)
P-256/384 TLS Key exchange (WPA2 with EAP-TLS & HTTPS)
All the cryptographic algorithms that provided by the AP have NIST CAVP certificates, which are
listed in the tables of FCS_COP.1, other algorithms provided by BoringSSL have also been tested
with the NIST ACVTS system.
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 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 and protected by BE mechanism), 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-decrypted and used to decrypt data received and encrypted while locked.
l FCS_CKM.2(1): The TOE performs key establishment as part of EAP-TLS and TLS session
establishment. Table 8: Asymmetric Key Generation Asymmetric Key Generation enumerates
the TOE’S supported key establishment implementations (RSA/ECDH for TLS/EAP-TLS). The TOE
acts as a TLS client, the TOE only performs 800-56B encryption when participating in TLS_RSA_*
based TLS handshakes. Thus, the TOE does not perform 800-56B decryption.
l FCS_CKM.2(2): The TOE provides an SDP library for applications that uses a hybrid crypto scheme
based on 2048-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.
53
l 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 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.
l 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), TEE will call qsee_prng_getdata() API to generate a 256-bit AES key. 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).
When generating keys, DRBG is fed in with 384 bits length of entropy input, based on the entropy
analysis, this 384 bits stream contains more than 256-bits entropy which is the maximum length
of the generated keys, which could ensure that the TOE generates DEKs with sufficient entropy,
the generated key cannot be recovered with less work than a full exhaustive search of the key
space.
l FCS_CKM_EXT.3: The TOE takes the user-entered password and conditions/stretches this value
before combining the factor with other KEK. The TOE generates all non-derived KEKs using the
RAND_bytes() API call from its BoringSSL AES-256 CTR_DRBG to ensure a full 112/256-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.
l 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 KEK through a
secure direct overwrite (BLKSECDISCARD ioctl) of the wear-leveled Flash memory containing the
key followed by a read-verify. Document “Key Hierarchy Figure” further explains how each type
of plaintext key material is generated, stored and cleared.
l 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 Sensitive Data Protection
KEKs protecting sensitive data files in the user data partition by overwrite the DEK, KEK, and
then 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. Document “Key Hierarchy
Figure” further explains how each type of plaintext key material is generated, stored and
cleared.
l FCS_CKM_EXT.6: The TOE generates salt nonces (which are just salt values used in WPA2) using
its /dev/random
Table 9: Salt Generation
Salt value and size Used RBG Storage
User password salt (128-bit) BoringSSL’s AES-256 CTR_DRBG Flash filesystem
54
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)
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)
l 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 (65d184c9f337bb7f461060e3808e07164cb0d236) provides the
following cryptographic algorithms:
Table 10: Cryptographic Algorithms Provided by BoringSSL
SFR Algorithm Standard
FCS_CKM.1 (Key Gen) RSA/ECDSA FIPS186-4
FCS_CKM.2 (Key
Establishment)
ECDSA-based Key exchange,
RSA-based Key exchange
SP800-56A
SP800-56B
FCS_COP.1(1) (AES) AES CBC, CCMP, KW, KWP, GCM, CCM, XTS
FIPS 197, SP800-
38A/C/D/E/F
FCS_COP.1(2) (Hash) SHA-1, SHA-256/384/512 FIPS 180-4
FCS_COP.1(3) (Sign/Verify)
RSA/ECDSA Signature generation and
verification
FIPS 186-4
FCS_COP.1(4) (Keyed Hash)
HMAC-SHA-1, HMAC-SHA-256, HMAC-SHA-
384. HMAC-SHA-512
FIPS198-1
FCS_RBG_EXT.1 (Random)
CTR_DRBG
Hash_DRBG
SP800-90A
The TOE’s application processor Qualcomm Snapdragon 888 provides the following
cryptographic algorithms
Table 11: CAVP Certificates by Application Processor
SFR Module Algorithm Standard Certificates
FCS_COP.1(1)
(AES)
QTI Crypto
Engine Core
AES 128/256 CBC
FIPS 197, SP 800-
38A
A805
FCS_COP.1(1)
(AES)
Qualcomm (R)
Inline Crypto
Engine (UFS)
AES 128/256 XTS
FIPS 197, SP 800-
38E
A771
A772
FCS_COP.1(2)
(Hash)
QTI Crypto
Engine Core
SHA 1/256
Hashing
FIPS 180-4 A805
55
FCS_COP.1(3)
(Signature
services)
QTEE kernel HMAC-SHA-1/256 FIPS 186-4 A981
FCS_COP.1(4)
(Keyed Hash)
QTI Crypto
Engine Core
HMAC-SHA-1/256
FIPS 198-1 & 180-
4
A805
FCS_RBG_EXT.1
(Random)
(DRBG)
QTI Pseudo
Random
Number
Generator
DRBG Bit
Generation
SP 800-90A (Hash-
256)
A764
FCS_CKM_EXT.3 QTEE kernel KBKDF SP 800-108 A981
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 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 with 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 PBKDF v2 and
ROMix to fulfil the requirements for password conditioning.
Figure 1: Password conditioning diagram
56
The resulting derived key from this operation is used to decrypt the FBE DEK (document “Key
Hierarchy Figure” further explains on how this key is used in FBE) and to decrypt the Software
based protected key.
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, 512/256, 1024/384, and 1024/512-bits for HMAC-SHA-1, HMAC-SHA-256, HMAC-SHA-
384, and HMAC-SHA-512 respectively.
The TOE uses SHA together with algorithms in FCS_COP.1(3) for digital signature generation
and verification, SHA-1 is used to generate 160-bit message digest, SHA-256, SHA-384 and
SHA512 are used to generate 256-bit, 384-bit and 512-bit message digests respectively. The
TOE also uses SHA with algorithms in FCS_COP.1(4) and FCS_COP.1(5) for the hash value
generation.
l 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. The TOE does not establish the connection if the peer certificate is deemed
invalid, and notify to the application that making the HTTPS connection.
l FCS_IV_EXT.1: The TOE generates IVs by reading from /dev/random for use with all keys, which
is compliance with the requirements of table 11 of MDFPP31.
l FCS_RBG_EXT.1: The TOE provides two RBGs including:
1. A SHA-256 Hash_DRBG provided in the hardware of the Application Processor.
2. An AES-256 CTR_DRBG provided by BoringSSL.
The AES-256 CTR_DRBG that comes with BoringSSL is the only RBG present in the ColorOS and
available for other user applications that running upon the OS. 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 seeds the Hash_DRBG of Application Processor with its hardware noise source to ensure
at least 256-bits of entropy. The TOE then uses the output of Hash_DRBG to continuously fill the
Linux Kernel Random Number Generator (LKRNG) input pool, then the TOE seeds its BoringSSL
AES-256 CTR_DRBG using 384-bits of data from /dev/random, which get data from the LKRNG
input pool, thus ensuring at least 256-bits of entropy can be got for the generated random
numbers. The TOE uses its BoringSSL DRBG for all random generation including keys, IVs and
salts.
l 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),
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.
l 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. Certificates are stored in files using UID-based permissions and an API virtualizes the
access. 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.
57
The TOE also provides additional protections on keys beyond including key attestation, to allow
enterprises and application developers the ability to ensure which keys have been generated
securely within the phone.
Document “Key Hierarchy Figure” further explains how each type of plaintext key material is
generated, stored and cleared.
l FCS_STG_EXT.2: The TOE employs a key hierarchy that protects all DEKs and KEKs, see
document “Key Hierarchy Figure” for more information.
Long-term Trusted channel Key Material (LTTCKM, i.e., Bluetooth and WiFi keys) are encrypted
using AES-256-GCM encryption within their respective configuration files.
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 Android Key Store.
l 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 (GCM). The TOE protects
the Wi-Fi LTTCKM keys using an AES-GCM-256 key protected by the TOE’s secure key storage
(KeyStore). The TOE protects the BT LTTCKM keys through an AES-CBC-256 key protected by
TEE, and then a HMAC-SHA-256 key protected by TEE.
l FCS_TLSC_EXT.1: The TOE provides mobile applications (through its Android API) the use of TLS
version 1.2 together with the ciphersuites defined in Section 6.1.2.22 to all the applications that
running on the ColorOS, and the TOE requires no configuration other than using the appropriate
library APIs as described in the Admin Guidance. The TOE also supports to import certificate for
the applications use.
When an application uses the APIs provided in the Admin Guide to attempt to establish a trusted
channel connection based on 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 TOE supports client (mutual) authentication. The TOE
in its evaluated configuration and, by design, supports elliptic curves for TLS (P-256 & P-384)
and has a fixed set of supported curves (thus the admin cannot and need not configure any
curves).
No additional configuration is needed to restrict allow the device to use the supported cipher
suites, as only the claimed cipher suites are supported in the aforementioned library as each of
the aforementioned ciphersuites are supported on the TOE by default or through the use of the
TLS library.
While the TOE supports the use of wildcards in X.509 reference identifiers (SAN and CN), the
TOE does not support certificate pinning. If the TOE cannot determine the revocation status of a
peer certificate, the TOE rejects the certificate and rejects the connection.
l FCS_TLSC_EXT.2: The TOE supports Elliptic Curves Extension of NIST curves (secp256r1,
secp384r1) in the Client Hello handshake message by default.
7.3 User Data Protection
The User data protection function is designed to fulfill the following security functional requirements:
l FDP_ACF_EXT.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).
An example of a normal permission is the ability to vibrate the device:
android.permission.VIBRATE. This permission allows an application to make the
58
device vibrate, and an application that does not request (or declare) this permission
would have its vibration requests ignored.
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.
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 its Manifest file.
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.
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).
4. Signature|System - 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 into a system image which need to share specific features
explicitly because they are being built together.
An example of a Signature|System 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 into 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.
59
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 11.0 (Level 30) API found here:
https://developer.android.com/about/versions/10/features 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. Below table shows a series of
functional categories centered on common functionality.
Table 12: Function Categories
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
Management
Date time, Reboot/Shutdown, Sleep, Force-close
application, Administrator Enrollment
Wi-Fi, Bluetooth, USB Access Wi-Fi, Bluetooth, USB tethering, debugging and file
transfer
Mobile Device Management &
Administration
MDM APIs
Peripheral Hardware NFC, Camera, Headphones
Security & Encryption Certificate/Key Management, Password, Revocation
rules
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
60
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.
l FDP_ACF_EXT.2: The TOE allows an administrator to allow sharing of the enterprise profile
address book with the normal profile. Each application group (profile) has its own calendar as
well as keychain (keychain is the collection of user [not application] keys, and only the user can
grant the user’s applications access to use a given key in the user’s keychain), thus the personal
and work profiles do not share calendar appointments nor keys.
l FDP_DAR_EXT.1: The TOE provides Data-At-Rest AES-256 XTS hardware encryption (also known
as FBE, file-based encryption) for all data stored on the TOE in the user data partition (which
includes both user data and TSF data). FBE provide the Credential Encrypted (CE) storage
locations available to applications, which is the default storage location and only available after
the user has unlocked the device.
The TOE also has TSF data relating to key storage for TSF keys not stored in the system’s Android
Key Store. The TOE separately encrypts those TSF keys and data. Additionally, the TOE includes
a read-only 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.
l 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 developer opt-in for
SDP, all data that is received on the device destined for that application is treated as sensitive.
This library provides two mechanisms, Authenticated Encryption (AE) and Brief Authenticated
Encryption (BE), using the symmetric and asymmetric key scheme respectively. When the AE
mechanism is used, the library calls into the TOE to generate an AES key that acts as a master
KEK for the SDP encryption process. The AE mechanism could encrypt or decrypt data only when
the device is unlocked. When the BE mechanism is used, the library calls into the TOE to generate
an RSA key that acts as a master KEK for the SDP encryption process. When an application that
uses BE mechanism receives incoming data while the device is locked, an 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 decrypted 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 could re-encrypts it with AE
mechanism.
l FDP_IFC_EXT.1: The TOE supports the installation of VPN Client applications, which ensures all
traffics other than traffic necessary to establish the VPN connection go through the VPN tunnel.
The TOE routes all packets through the kernel’s IPsec interface (ipsec0) when the VPN is active.
When the kernel routes these data packets, it will determine whether to protect, bypass or
discard according to the policy configured by the user.
There is no difference in the routing of IP traffic when using any supported baseband protocols
(e.g. Wi-Fi or, LTE). 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.
l 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,
61
the biometric sensor takes an image of the presented biometric for comparison to the enrolled
templates. The captured image is used to generate the features points and then 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.
Password authentication is required prior to managing the authentication templates, include
viewing or modifying the template information, enrolling a new template, unenrolling the
existing template, trying to enable or disable the biometric authentication mechanism.
l 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.
l 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 BR/EDR and LE. Mobile
applications can use the following Android APIs for TLS, HTTPS, and Bluetooth respectively:
1. javax.net.ssl.SSLContex
http://developer.android.com/reference/javax/net/ssl/SSLContext.html
2. javax.net.ssl.HttpsURLConnection
http://developer.android.com/reference/javax/net/ssl/HttpsURLConnection.html
3. android.bluetooth
http://developer.android.com/reference/android/bluetooth/package-summary.html
7.4 Identification and Authentication
The Identification and authentication functions are designed to fulfill the following security functional
requirements:
l FIA_AFL_EXT.1: The TOE maintains in persistent storage, for each user, the number of failed
password logins since the last successful login, and upon reaching the maximum number of
incorrect logins, the TOE performs a full wipe of all protected data (and in fact, wipes all user
data). An administrator can adjust the number of failed logins for the cryptlock screen from the
default of 10 failed logins to a value between 0 (deactivate wiping) and 50 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 persistent secure storage and increments the counter before
validating the password. Upon successful validation of the password, this counter is reset back
to zero. By storing the counter persistently, and by incrementing the counter prior to validating
it, the TOE ensures a correct tally of failed attempts even if it loses power.
The TOE also support fingerprint, and the phone allows the user to unlock the device using his
or her fingerprint. The TOE (through a separate counter) allows users up to 5 attempts to unlock
the device via fingerprint before temporarily disabling fingerprint authentication for 30 seconds.
While the TOE has temporarily disabled the finger sensor, the user can input their password to
unlock the phone. After a total of 4 failed rounds of attempted fingerprint authentications (20
total unlock attempts), the TOE completely disables the fingerprint sensor. Once the TOE has
disabled the fingerprint sensor, it remains disabled until the user enters their password to unlock
the device. Note that restarting the phone at any point disables the fingerprint sensor
62
automatically until the user enters a correct password and unlocks the phone, and therefore TOE
restart disruptions are not applicable for biometric authentication mechanisms.
l 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.
l FIA_BLT_EXT.2: The TOE prevents data transfer of any type until Bluetooth pairing has
completed, there is no RFCOMM nor L2CAP data transfer can occur before pairing. Additionally,
the TOE supports OBEX (OBject Exchange) through L2CAP (Logical Link Control and Adaptation
Protocol).
l FIA_BLT_EXT.3: The TOE rejects duplicate Bluetooth connections by only allowing a single
session per paired device. This ensures that when the TOE receives a duplicate session attempt
while the TOE already has an active session with that device, then the TOE ignores the duplicate
session.
l 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.
l FIA_BMG_EXT.1: The TOE’s fingerprint sensor provides a FAR of 1:100,000 with an FRR of 3%,
which meets the requirements for FIA_BMG_EXT. Calculations of FAR/FRR/SAFAR can be found
in the Appendix A: FAR/FRR Calculation.
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 fingerprint authentication factor is 1:5,000.
l 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 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.
l FIA_TRT_EXT.1: The TOE limits the number of authentication attempts through the UI to no more
than 5 attempts within 30 seconds. Thus if the current [the nth] and prior four authentication
attempts have failed, and the (n - 4)th attempt was less than 30 second ago, the TOE will prevent
any further authentication attempts until 30 seconds has elapsed. Note as well that the TOE will
wipe itself when it reaches the maximum number of unsuccessful authentication attempts (as
described in FIA_AFL_EXT.1 above).
l FIA_UAU.5: The TOE allows the user to authenticate using either a password or fingerprint sensor.
Upon boot, the first unlock screen presented requires the user to enter their password to unlock
the device. The fingerprint sensor is enabled only after 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 by using a fingerprint authentication. The TOE verifies user’s
password by sending hash of the password to the TEE. FIA_PMG_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, biometric authentication is not accepted to permit the referenced functions.
The TOE’s evaluated configuration disallows other authentication mechanisms, such as PIN, or
Smart Lock mechanisms (on-body detection, trusted places, trusted devices, trusted face,
trusted voice).
63
l FIA_UAU.6(1)/(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 -> Fingerprint, face & password -> Set Lock screen password/Add
fingerprint” menu in the TOE’s user interface. The TOE can disable Smart Lock through
management controls. Only after entering their current user password the user then can elect
to change their password.
l 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.
Further, the TOE provides no feedback other than whether the fingerprint unlock attempt
succeeded or failed.
l 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.
l FIA_UAU_EXT.2: The TOE allows a user to perform the actions assigned in FIA_UAU_EXT.2.1
without first successfully authenticating.
Actions that may access internal Flash storage (e.g. take screen shots, take pictures) are
automatically done by the TOE, user could not change the storage location or rename them.
When configured, the user can also launch Breeno Assistant to initiate some features of the
phone. However, If the actions require accessing 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.
l 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 into TOE’s Trust Anchor Database. If the TOE detects the absence of either the
extension or flag, the TOE will import the certificate as a user public key and add it to the
keystore (not the Trust Anchor Database). 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.
l FIA_X509_EXT.2: 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
plus OPPO’s additional 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 user 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
64
establish a connection with the server acting as the OCSP Responder, the TOE will not deem the
peer’s certificate as valid and will not establish a TLS connection with the peer.
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.
l FIA_X509_EXT.3: The TOE’s provides applications the java.security.cert.CertPathValidator API
Class of methods for validating certificates and certification paths (certificate chains establishing
a trust chain from a certificate to a trust anchor). This class is also recommended to be used by
third-party Android developers for certificate validation. However, TrustedCertificateStore must
be used to chain certificates to the Android System Trust Anchor Database (anchors should be
retrieved and provided to PKIXParameters used by CertPathValidator).
The available APIs may be found here:
http://developer.android.com/reference/java/security/cert/package-summary.html.
7.5 Security Management
The Security management function is designed to fulfill the following security functional requirements:
l FMT_MOF_EXT.1: The TOE provides the management functions described in Table 4 in section
6.1.5.2. 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).
l FMT_SMF_EXT.1: The TOE provides all management functions indicated as mandatory (“M”) by
Table 4. 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).
l FMT_SMF_EXT.2: The TOE offers MDM agents the ability to wipe protected data (including
sensitive data), remove Enterprise applications, and remove all device stored Enterprise
resource data upon un-enrollment and factory reset. 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.
7.6 Protection of the TSF
The Protection of the TSF function is designed to fulfill the following security functional requirements:
l FPT_AEX_EXT.1: The Linux kernel of the TOE’S Android operating system provides address space
layout randomization utilizing the get_random_long(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.
l FPT_AEX_EXT.2: The TOE utilizes 5.4 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
65
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
l 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.
l 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.
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->Software Update) while the phone is running. The TOE will verify the digital
signature of the new OTA before applying the new firmware.
For the install of the ColorOS build through fashboot interface, the user must apply “Unlock
permission” on ColorOS, and unlock the device’s bootloader via installing Unlock APK, “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.
USSD and MMI code are not able to modify user or TSF data from the dialer at the TOE’s locked
state.
l 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 OPPO’s private key can be used to access a device’s JTAG interface. The OPPO private
key corresponds to the OPPO ECDSA P-384 public key (a SHA-384 hash of which is fused into the
TOE’S application processor).
JTAG pads are located on the printed circuit board, which is covered by the rear panel and the
battery, they are inaccessible without breaking the rear panel. JTAG pads include TCK, TMS, TDI,
TDO, TRST_N and SRST_N.
l 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 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. Note as well that the TOE does not use the user’s fingerprint
template to encrypt / protect key material. As the TOE encrypts all keys stored in Flash, and
66
encrypts all the fingerprint templates in the TEE of AP, upon boot-up, the TOE must first decrypt
any keys in order to utilize them.
l 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: vold,
wpa_supplicant, and the Android Key Store.
1. vold and QCT’s 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. Android 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).
l FPT_KST_EXT.3: The TOE does not provide any way to export plaintext DEKs or KEKs (including
all keys stored in the Android KeyStore) 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 (TEE) 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 kernel which holds the key in order to encrypt and decrypt reads and writes to the encrypted
user data partition files 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 application do not have any access to any system-level components and only have
access to keys that the application has imported into the Android KeyStore. 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 user’s 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.
l 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, 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.
l FPT_STM.1: The TOE requires time for the Package Manager (which installs and verifies APK
signatures and certificates), image verifier, wpa_supplicant, and Android 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 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.
67
l 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
it cryptographic algorithms to ensure it is working correctly. Should any of the tests fail, the TOE
will halts the boot process, and forces a reboot of the device.
Table 13: Power-up Cryptographic Algorithm Known Answer Tests
Algorithm Implemented in Description
AES
encryption/decryption
BoringSSL Comparison of known answer to calculated value
SHA hashing BoringSSL Comparison of known answer to calculated value
RSA signature
generation and
verification
BoringSSL Comparison of known answer to calculated value
ECDSA signature
generation and
verification
BoringSSL Comparison of known answer to calculated value
HMAC-SHA BoringSSL Comparison of known answer to calculated value
DRBG random bit
generation
BoringSSL Comparison of known answer to calculated value
AES
encryption/decryption
Application
Processor
Comparison of known answer to calculated value
SHA hashing Application
Processor
Comparison of known answer to calculated value
HMAC-SHA Application
Processor
Comparison of known answer to calculated value
l FPT_TST_EXT.2(1): The TOE ensures a secure boot process no matter in normal boot mode or
auxiliary boot mode, i.e., fast boot. In both boot modes, 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. 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).
l FPT_TUD_EXT.1: The TOE’S user interface provides a method to query the current version of the
TOE software/firmware (ColorOS 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.
l 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 ColorOS of the TOE requires that all applications shall be signed with a valid signature before
installing the application.
68
Additionally, ColorOS allows updates through OPPO App Market and Google Play updates,
including both APK and APEX files. Both file types use Android APK signature format and the TOE
verifies the accompanying signature prior to installing the file (additionally, ColorOS ensures that
updates to existing files use the same signing certificate).
l ALC_TSU_EXT.1: To make timely security updates to the TOE, the following procedures are in
place:
a. Security vulnerabilities reporting:
OPPO supports a Security Response Center for ColorOS outlined here:
https://security.oppo.com/en/. This allows developers or users to search for, file, and
vote on vulnerabilities that need to be fixed. This helps to ensure that all vulnerabilities
that affect large numbers of people get pushed up in priority to be fixed. The user could
login to the website from computer-based web browser, or directly establish a trusted
channel web connection to securely file the vulnerability by following the set-up steps
to establish a secure HTTPS/TLS/EAP-TLS connection from the TOE.
b. Security vulnerability response process:
OPPO creates updates and patches to resolve reported issues as quickly as possible. The
delivery time for resolving an issue depends on the severity, normally from several days
to 1 month for the critical or high-risk vulnerabilities, or up to 3 months for medium or
low-risk vulnerabilities. The updates or patches are tested before releasing to ensure
they will not adversely impact on other functions of the product. Once the testing are
finished, OPPO rolls out the updates and patches, then user could query the updates of
the TOE via OTA as addressed in FPT_TUD_EXT.1, and update the TOE by following the
[CC_GUIDE].
c. Security updates announcement:
All the vulnerabilities are announced on website: https://security.oppo.com/en/notice.
OPPO commits to pushing out monthly security updates for the ColorOS operating
system (including the Java layer and kernel, not including applications). Monthly security
updates have historically been supported on OPPO products for 2 years after release.
These systematic updates are designed to address the highest security problems as
quickly as possible and allows OPPO to ensure their mobile phone products remain as
safe as possible and any issues are addressed promptly.
7.7 TOE Access
The TOE access function is designed to fulfill the following security functional requirements:
l 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.
69
7.8 Trusted Path/Channels
The Trusted path/channels function is designed to fulfill the following security functional requirements:
l FTP_ITC_EXT.1: The TOE provides secured (encrypted and mutually authenticated)
communication channels between itself and other trusted IT products through the use of IEEE
802.11-2012, 802.1X, and EAP-TLS and TLS, HTTPS. 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. The TOE also provides the OTA via HTTPS and TLS channel.
70
8 TSF Inventory
Below is a list of user-mode TSF binaries and libraries that are used to provide the security
functionality of the TOE. Each of the below are built with the "-fstack-protector" complier option to
protect overflow stack attack.
Table 14: TSF name and path
Name Path Security Function
keystore /system/bin KeyStore
gatekeeperd /system/bin Key Management
qseecomd /vendor/bin DAR
time_daemon /vendor/bin Time
vold /system/bin DAR
adbd /apex/com.android.adbd/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 /system/bin/
Recovery/Initial
Image Load
recovery /system/bin Recovery
mke2fs /system/bin Recovery
charger /system/bin Recovery
init /system/bin Recovery
libQSEEComAPI.so
system/vendor/lib,
system/vendor/lib64
TrustZone Daemon
com.coloros.ocs.opencapabilityservice /my_stock/app/OpenCapabilityService DAR
wpa_supplicant /vendor/bin/hw WLAN
71
Appendix A: FAR/FRR Calculation
A.1 Fingerprint Recognition Description
The TOE implements the in-display optical fingerprint sensor as the biometric authentication
mechanism.
OLED screen that comes with the TOE emits light when it requires the fingerprint to be authenticated,
user put his/her fingerprint right upon the fingerprint sensor, the light illuminate user’s finger, the
reflected lights are focused by the lens and finally collected by the fingerprint sensor, then the sensor
generates the picture of the fingerprint and grabs the features points as the matching template during
the registration phase, or compare the grabbed feature points to the stored template during the
authentication phase.
Figure 2 shows the mechanism of in-display optical fingerprint sensor.
Figure 2: In-display optical fingerprint sensor
A.2 Testing Environment Setup
Since the data set would be too large for the phone to calculate directly, so offline test approach is taken
for calculating the FAR/FRR. Vendor setup the testing environment as shown below, which uses all the
same hardware as the TOE, but a general PC is used instead of the TOE to run the fingerprint recognition
firmware and calculate the results. The firmware is also same as the one running in the TOE.
1. Fingerprint sensor model: GW9578 manufactured by Goodix
2. Fingerprint matching firmware: v03.02.02.216 by Goodix
3. Testing equipment: Samsung OLED is used, and fingerprint is placed under the OLED screen.
4. Fingerprints collection method: Tester put his fingerprint on the OLED and initiate the fingerprint
collection process.
A.3 Data Set Capture
1. Data set is generated by real fingers, each tester provides one fingerprint.
2. Fingerprint template: For each fingerprint, 20 small images (178 * 178 pixels) of the different
parts of the fingerprint are captured, and then concatenated together as the full fingerprint
template for future matching with, the resolution of full template varies because valid
information of each captured image varies.
3. Matching candidate: For each fingerprint, 50 small images (178 * 178 pixels) are captured as
the authentication input, which will be compared with the full template generated in above step.
A.4 FAR/FRR Calculation
1. False Acceptance Rate (FAR) calculation:
For a single fingerprint, each matching candidate is compared with all the templates.
Matching times = Numbers of fingerprints * 50 * (numbers of fingerprints - 1)
FAR = Numbers of false accepted fingerprints / Matching times
2. False Rejection Rate (FRR) calculation:
OLED
Lens
Sensor
72
For a single fingerprint, each matching candidate is compared with its own template.
Matching times = Numbers of fingerprints * 50
FRR = Numbers of false rejected fingerprints / Matching times
A.5 FAR/FRR Testing Results
Three rounds testing are performed for calculation of FAR, and since different environmental affects
the fingerprint recognition, so eight rounds of testing are performed to simulate all possible
circumstances in real world.
Table 15 shows the testing results of FAR and FRR.
FAR
Rounds Fingerprints Samples False Accepted Matching Times
Round 1 (Normal Temp.) 310 50 19 4789500
Round 2 (Normal Temp.) 306 50 11 4666500
Round 3 (Normal Temp.) 314 50 17 4914100
The worst FAR shown in round 1 is 19 / 4789500 ≈ 1:250000
FRR
Rounds Fingerprints Samples False Rejected Matching Times
Round 1 (Normal Temp.) 60 50 18 3000
Round 2 (Wet finger) 60 50 66 3000
Round 3 (Hand cream) 60 50 12 3000
Round 4 (High light 1) 60 50 132 3000
Round 5 (High light 2) 60 50 292 3000
Round 6 (Low Temp.) 60 50 74 3000
Round 7 (Dirty finger) 60 50 39 3000
Round 8 (Sweat Finger) 60 50 56 3000
Count with all the false rejected values: 689 / 24000 ≈ 3%
Table 15: FAR and FRR Testing Rounds
Fingerprint manufacturer claims the FAR as 1:150,000 and FRR as 3%, which we could find out that the
manufacturer claimed values fall into the testing results. Considering the worst-case scenario in the
real world, OPPO claims the FAR as 1:100,000 and FRR as 3%.