Security Target: 0350b

HD65256D Security Target

– Public Version

HD65256D-CC-ST-0002

HD65256D Version 01

Smartcard Security Target

- Public Version -

Renesas Technology Corp.

Revision 2.0

23 February, 2007

Copyright 2007, Renesas Technology Corp. All rights reserved.

HD65256D Security Target

– Public Version

Revision

Revision Date

Rev. 1.0

Rev. 2.0

28 Sept.,

2006

23 Feb.,

2007

Section

0.4

Description

Release

Small modifications in reference information

HD65256D-CC-ST-0002

Revision 2.0, 23 February, 2007 Page ii

HD65256D Security Target

– Public Version

0 Preface

HD65256D-CC-ST-0002

0.1 Objectives of Document

This document defines the Security Target for evaluation of the Renesas HD65256D. It is intended to comply with the BSI-PP-0002 Protection Profile (see [BSI-PP-0002]). Although no evaluated conformance claim is made, it is also intended to conform as far as possible with the requirements of the IC package of the

SCSUG Protection Profile, and to provide support for operating system and application software that aims to meet SCSUG requirements.

0.2 Scope of Document

This document defines the Security Target as required by [CC/1]. This is a Public version of the document used in the evaluation process.

0.3 Intended Reader ship

Developers concerned with certification of the TOE.

Developers of Smartcard Embedded Software to run on the TOE.

Evaluators and certifiers of the TOE.

0.4 Related Documents

A reference of the form [REF, n] refers to section n of REF.

Liter atur e

[BSI-PP-0002] Smartcard IC Platform Protection Profile, v1.0, Eurosmart, July 2001

[AIS31] Functionality classes and evaluation methodology for physical random number generators,

AIS 31, v3.1 (part of Bundesamt für Sicherheit in der Informationstechnik Application Notes and Interpretation of the Scheme), Certification Body of the BSI

[AIS20] Functionality classes and evaluation methodology for deterministic random number generators, AIS 20, v1 (part of Bundesamt für Sicherheit in der Informationstechnik

Application Notes and Interpretation of the Scheme), Certification Body of the BSI

[CC/1]

[CC/2]

[CC/3]

ISO/IEC 15408-1:1999 (E) Information Technology – Security techniques – Evaluation criteria for IT security – Part 1: Introduction and general model, 1999-12-01

ISO/IEC 15408-2:1999 (E) Information Technology – Security techniques – Evaluation criteria for IT security – Part 2: Security functional requirements, 1999-12-01

ISO/IEC 15408-3:1999 (E) Information Technology – Security techniques – Evaluation criteria for IT security – Part 3: Security assurance requirements, 1999-12-01

Note: the combination of all 3 parts of ISO 15408 is also referred to in this document as "Common

Criteria" or "CC".

[PA] Smartcard Integrated Circuit Platform Augmentations, v1.0, Atmel, Hitachi Europe, Infineon

Technologies & Philips Semiconductors, March 2002

Documents and User Guidance

[HM] Renesas 32-bit Smart Card Microcomputer AE-5 Series AE56D (HD65256D) Hardware

Manual, Rev. 1.1, Renesas Technology Corp., 10 August, 2006

[OPT] Option List for Mask ROM Data (for HD65256D [AE56D]) (about Mask ROM data), v.1.0R,

Renesas Technology Corp., 5 July 2005

Revision 2.0, 23 February, 2007 Page iii

HD65256D Security Target

– Public Version

HD65256D-CC-ST-0002

[EEPOPT] Option List for EEPROM Write (for HD65256D [AE56D]), v.1.10R, Renesas Technology

Corp., 17 November 2005

[PM] H8SX Software Manual (Renesas 32-bit CISC Microcomputer H8SX Family), Revision 3.0,

Renesas Technology Corp., 14 September, 2004

[UGM1] HD65256D User Guidance Manual – Information for software developers using the

HD65256D in security–conscious applications, Rev. 1.10, Renesas Technology Corp., 20

July, 2006

[UGM2] KURA Chip User Guidance Manual – Information for users of the security chip, Rev. 1.00,

Renesas Technology Corp., 7 June, 2006

0.5 Document Str ucture

This document follows the structure set out in [CC/1].

Note that sub-sections are structured to show parts that originate from [BSI-PP-0002], [PA] and other sources.

0.6 Outstanding Issues

None.

0.7 Glossar y

Ter m Meaning

CC

CPU

CRC

DES

DFA

DPA

EAL

ECB

CBC

EEPROM

Embedded Software

Cipher Block Chaining

A mode of DES encryption.

Common Criteria (ISO 15408)

Central Processing Unit

Cyclic Redundancy Check

Data Encryption Standard

Differential Fault Analysis

Differential Power Analysis

Evaluation Assurance Level

Electronic Code Book

A mode of DES encryption.

Electronically Erasable Programmable Read-Only Memory

Software held in the chip, having been developed by users of the TOE. Such software generally includes an operating system and may include all or part of applications. There are two types of Embedded Software:

Hard-coded – held in ROM

Soft-coded – held in EEPROM or RAM.

The chip does not depend on such software, and Embedded Software is not part of the

TOE. However, hard-coded Embedded Software will be included in the ROM of any issued TOE at manufacturing time.

Note that Embedded Software includes all software on a TOE other than the IC

Dedicated Software.

Embedded Software is also referred to as ‘Smartcard Embedded Software’ (especially in

[BSI-PP-0002]).

EWE

FMU

HW RNG

An interrupt generated by the TOE whenever an attempt is made to write to EEPROM.

Firewall Management Unit – a feature of the TOE that limits the memory areas available.

Hardware random number generator (physical random number generator)

IC Integrated Circuit

IC Dedicated Software Software developed by Renesas and embedded in the IC. (Adopted from [BSP-PP-0002])

IC Dedicated Test

Software

ISC

Software developed by Renesas for testing the TOE during manufacture. This software is part of the TOE, but is not available for general use by operating systems, applications or end-users in phase 7 of the lifecycle (see section 2.3).

Integrated Security Concept

Revision 2.0, 23 February, 2007 Page iv

HD65256D Security Target

– Public Version

Ter m

IT

LNRRT

LSERB

LSI

LUART

Manufacturing

Identification Data

MCU

Option List

PP

RAM

Renesas

Reset state

RNG

ROM

SFP

SFR

Smartcard

SOF

ST

TOE

TOE Delivery

TOE Manufacturer

TSC

TSF

TSF Data

User Data

User Mode

WDT

Meaning

HD65256D-CC-ST-0002

Information Technology

Local NRz Receive/Transmit

Local SERial Bus

Large Scale Integration

Local UART

Some basic data injected into EEPROM, enabling traceability of an IC to the lot and line in which it was manufactured, the Smartcard Embedded Software present, and the versions of masks and specifications applicable.

Micro Computer Unit

A form supplied by Renesas and filled in by a TOE customer, specifying various options for the manufacture of TOE ICs for that customer. The aspect of particular interest to this security target is :

Selection of whether pre-personalisation data injection is required

The option list also describes the content and structure of the manufacturing identification data that Renesas will inject (see section 2.4.2).

Protection Profile

Random Access Memory

Refer to Renesas Technology Corp. (http://www.renesas.com/)

A state in which the chip does not execute instructions or engage in input/output. The chip can exit the reset state by receiving an external reset.

See also section 6.1.

Random number generator

Read-Only Memory

Security Function Policy

Security Functional Requirement

(as used in [BSI-PP-0002]) Composition of the TOE, the Smartcard Embedded Software,

User Data and the package (the smartcard carrier).

Strength of Function

Security Target

Target of Evaluation. TOE consists of the chip (IC) and other materials and data.

However, the term is sometimes used to indicate just the chip.

The point at which the TOE is delivered, as shown in section 2.3. This may be either in the form of wafers (at the end of phase 3) or as packaged modules (at the end of phase 4).

(As defined in section 8.7 of [BSI-PP-0002]) The IC developer and manufacturer. If the

TOE is delivered after phase 4 (i.e. as packaged modules, rather than wafers) then this is also the packager.

For the HD65256D, the TOE Manufacturer refers to Renesas.

TSF Scope of Control

TOE Security Functions

Data created by and for the TOE and that might affect the operation of the TOE.

All data managed by the Smartcard Embedded Software in the application context. User data comprises all data in the final smartcard IC except for the TSF data.

The mode of operation after TOE Delivery. The TOE is set to this mode just before delivery, which renders the IC Dedicated Test Software permanently unavailable.

Watchdog Timer – a feature of the chip that enables embedded software to be regularly executed during the operation of the IC. This allows checks to be made on the execution environment to help detect potential attacks or insecure conditions.

Revision 2.0, 23 February, 2007 Page v

HD65256D Security Target

– Public Version

1.

2.

3.

4.

5.

HD65256D-CC-ST-0002

Table of Contents

ST Introduction ...............................................................................................................1

1.1

ST Identification ..................................................................................................1

1.2

TOE Identification ...............................................................................................1

1.3

ST Overview........................................................................................................2

1.4

CC Conformance Claim .......................................................................................3

TOE Description .............................................................................................................4

2.1

HD65256D Product Description...........................................................................4

2.1.1

Hardware..................................................................................................4

2.1.2

Software...................................................................................................6

2.1.3

Documents ...............................................................................................7

2.2

TOE Intended Usage ............................................................................................7

2.3

TOE Lifecycle .....................................................................................................7

2.3.1

Test and User Modes ..............................................................................10

2.3.2

TOE Delivery.........................................................................................10

2.4

TOE Environments ............................................................................................10

2.4.1

Development Environment .....................................................................10

2.4.2

Injection of Manufacturing Identification and Secret Data ......................11

TOE Security Environment............................................................................................13

3.1

Assets ................................................................................................................13

3.2

Assumptions ......................................................................................................14

3.2.1

Assumptions from [BSI-PP-0002] ..........................................................14

3.2.2

Assumptions from [PA]..........................................................................15

3.2.3

Other Assumptions .................................................................................15

3.3

Threats...............................................................................................................15

3.3.1

Threats Defined in [BSI-PP-0002]..........................................................15

3.3.2

Other Threats..........................................................................................18

3.4

Organisational Security Policies .........................................................................20

3.4.1

Policy Requirement from [BSI-PP-0002]................................................20

3.4.2

Policy Requirement from [PA] ...............................................................20

Security Objectives........................................................................................................22

4.1

TOE Security Objectives....................................................................................22

4.1.1

Objectives from [BSI-PP-0002]..............................................................22

4.1.2

Objectives Based on [PA].......................................................................24

4.1.3

Other Objectives.....................................................................................25

4.2

Environment Security Objectives .......................................................................26

4.2.1

Environment Security Objectives from [BSI-PP-0002] ...........................26

4.2.2

Other Environment Security Objectives..................................................28

IT Security Requirements ..............................................................................................29

5.1

TOE Security Requirements...............................................................................29

5.1.1

TOE Security Functional Requirements from [BSI-PP-0002] .................30

5.1.2

TOE Security Functional Requirements Based on [PA] ..........................35

5.1.3

Other TOE Security Functional Requirements ........................................36

5.1.4

TOE Security Assurance Requirements ..................................................38

5.2

Security Requirements for the Environment .......................................................39

5.2.1

Security Requirements for the IT Environment from [PA] ......................39

5.2.2

Security Requirements for the Non-IT Environment ...............................41

Revision 2.0, 23 February, 2007 Page vi

HD65256D Security Target

– Public Version

6.

HD65256D-CC-ST-0002

TOE Summary Specification .........................................................................................43

6.1

TOE Security Functions .....................................................................................43

6.2

Correspondence Between TOE Security Function and SFR ................................47

6.3

Assurance Measures...........................................................................................47

7.

8.

PP Claims......................................................................................................................49

7.1

PP Reference......................................................................................................49

7.2

PP Tailoring .......................................................................................................49

7.3

PP Additions ......................................................................................................49

Rationale .......................................................................................................................50

8.1

Security Objectives Rationale ............................................................................50

8.2

Security Requirements Rationale .......................................................................52

8.2.1

Dependencies .........................................................................................56

8.3

TOE Summary Specification Rationale ..............................................................58

8.4

Assurance Requirements and Strength of Function Rationale .............................59

8.5

Mutual Support and Internal Consistency...........................................................59

8.6

PP Claims Rationale...........................................................................................59

Revision 2.0, 23 February, 2007 Page vii

HD65256D Security Target

– Public Version

HD65256D-CC-ST-0002

Revision 2.0, 23 February, 2007 Page viii

HD65256D Security Target

– Public Version

HD65256D-CC-ST-0002

1. ST Intr oduction

The ST aims to provide potential users of the TOE with

A definition of the main properties of the IC that are evaluated and certified independent of any software

Confidence in IC properties that can be used to build an integrated TOE (i.e. IC + operating system + other application software).

1.1

Title:

ST Identification

HD65256D Version 01 Smartcard Security Target – Public Version –

Revision: 2.0

Provided by: Renesas Technology Corp.

This Security Target applies to the Renesas HD65256D integrated circuit (version 01)

(as defined in detail in the configuration list for the evaluation).

This public version of the HD65256D Security Target (also known as “ ST-lite” ) is abridged from the evaluated version of the full Security Target (revision 4.0) with the approval of the

Certification Body.

1.2 TOE Identification

The TOE configuration is summarised in the table below:

Item Type

Hardware

Software

Item integrated circuit

Table 1-1: TOE Configuration

HD65256D smartcard

IC Dedicated Test Software

Test ROM software

Software RNG online test software

Ver sion

01

0.10

2.20

Form of delivery

Wafer or packaged module (see section 2.3)

Included in HD65256D test ROM

1.1

1.10

Hardcopy: provided as a part of

[UGM1]. (This is implemented in the

Embedded Software by the user)

Hardcopy

Hardcopy

Document Hardware Manual*

Document User Guidance Manual (for software developers)*

Document User Guidance Manual (for chip users)*

Document Option List for Mask ROM

Data*

Document Option List for EEPROM

Write*

1.00

1.0R

1.10R

Hardcopy

Electronic data/Hardcopy

Electronic data/Hardcopy

Revision 2.0, 23 February, 2007 Page 1 of 59

HD65256D Security Target

– Public Version

HD65256D-CC-ST-0002

Note: These documents are written in Japanese. In order to support evaluation of the TOE, English versions of those documents are provided to the evaluation body.

Further description of the TOE is provided in section 2.1.

TOE

RNG online test software

(implemented on hardware)

ROM

IC Dedicated Test Software

(implemented on hardware)

Embedded Software

(implemented on hardware)

(out of the scope of TOE)

Chip

Hardware Manual

EEPROM Injection Option List

Option List

User Guidance for User

User Guidance for Software Developer

RNG online test software

(source code sample)

Figur e 1-1: Configuration of the TOE

Figure 1-1 shows the configuration of the TOE. The TOE consists of hardware, software, and documents. The software (as part of the TOE) is provided as being implemented on the hardware. Among software, the Embedded Software is outside the scope of the TOE. The RNG online test software is provided to the developer of the Embedded Software as a source code sample in [UGM1], and it is implemented in the TOE as the embedded software by the

Embedded Software developer.

1.3 ST Over view

This document is the ST for the Renesas HD65256D IC product, intended for use as a smart card

IC. The TOE complies with the Eurosmart Protection Profile developed by the Secure

Semiconductor Vendor Group [BSI-PP-0002]. However, the TOE also provides a number of additional security features that have been based on a long history of assisting software developers to implement secure Smartcard Embedded Software. These TOE-specific security features have been added to the ST.

The TOE is ideally suited for high security applications. Security has been built in from the start, forming an integral part of the whole Smartcard design concept. The whole development process (including secure chip design environment, secure production facilities and secure handling during shipment to the customer) is constantly reviewed in order to maximise the

Revision 2.0, 23 February, 2007 Page 2 of 59

HD65256D Security Target

– Public Version

HD65256D-CC-ST-0002 overall security package. The TOE can be delivered as packaged modules ready for embedding into a mobile equipment.

Many security features such as integrated sensors, distributed layout, random number generation,

DES coprocessor and power analysis attack protection are all included providing a strong onchip hardware security structure.

Uniquely, Renesas smartcard devices are fabricated using a MONOS (Metal Oxide Nitride

Oxide Silicon) EEPROM structure. MONOS advantages compared to standard EEPROM structures are high resistance to radiation disturbance, high reliability and endurance.

The TOE fulfils the requirements of Smart Card applications requiring large memory, high security and high speed secure authentication, data encryption or electronic signature. Examples include: e-money, e-ticket, and ID card.

Applications such as e-money are ever expanding in scope and consequently the need for greater memory storage for both data and program code is ever increasing. The TOE provides a significant increase in ROM for program storage over previous devices whilst ensuring a balance of EEPROM for data storage.

The move from single to multi-application on a single component is also rising due in part to new systems such as e-money and e-ticket. This requires not only additional memory for application data storage but also features such as FMU in order to provide data integrity between applications.

1.4 CC Confor mance Claim

This ST is compliant with [CC/1], [CC/2] and [CC/3].

Because the ST conforms to [BSI-PP-0002], it includes extended functionality classes defined in section 8 of [BSI-PP-0002]. The ST is therefore [BSI-PP-0002] conformant, [CC/2] extended and [CC/3] conformant. In addition, this ST includes some additional assumptions, threats, objectives and SFRs defined in [PA]. Therefore, this ST is also [PA] conformant. This ST deals with a life cycle that contains a phase which is outside of the scope of the life cycle of smartcard

LSI defined in [BSI-PP-0002] (see section 2.3).

The Assurance level is EAL4 augmented (for augmentations see section 5.1.4).

The strength of function is SOF-high.

Page 3 of 59 Revision 2.0, 23 February, 2007

HD65256D Security Target

– Public Version

HD65256D-CC-ST-0002

2. TOE Descr iption

2.1 HD65256D Pr oduct Descr iption

The TOE consists of the hardware shown in Figure 2-1, along with IC Dedicated Test Software, some embedded software, and reference and guidance documents. IC Dedicated Test Software is used in IC production only, and is not available to users.

As well as the functional interfaces, the IC surface is also considered as a TOE interface for some potential physical attacks, as described in section 3.3 of [BSI-PP-0002].

A block diagram of the chip is shown in Figure 2-1 below:

CPU

V

CC

V

SS

System control logic

WDT

(Optional)

FMU

Data Bus

Security logic

SCK

Address Bus

Clock generator

TCK

ROM

RAM

EEPROM

DES coprocessor

Interval timer 2/3

RNG

CRC coprocessor

LSERB

LUART

LNRRT

Interval timer 1

LSB

TXD

RXD

TDT

RDT

Figur e 2-1: Internal Block Diagram of the TOE

2.1.1 Hardware

The TOE is an integrated circuit for smartcard based around the high-speed CPU core (derived from Renesas’ widely used H8SX general purpose core). As can be seen from the block diagram in Figure 2-1, the MCU comprises the following major blocks in addition to the CPU: ROM,

RAM, EEPROM, random number generator (RNG), CRC coprocessor, DES coprocessor, three interval timers, WDT (optional), FMU, and three types of interfaces (LSERB, LUART, LNRRT).

For operation of the TOE, two kinds of external clocks (SCK, TCK) are input from outside of the

Revision 2.0, 23 February, 2007 Page 4 of 59

HD65256D Security Target

– Public Version

HD65256D-CC-ST-0002 chip. SCK is used for operation of internal circuits of the chip (6.70MHz to 6.86MHz). TCK is used for data transmission (input/output) via contactless interfaces and for operation of the

Interval timer 1 (212kHz or 424kHz).

CPU: the CPU can operate with 2.2V to 3.3V supply and a maximum internal clock frequency of 13.72MHz and is upwards compatible with the H8/300 core:

The instruction set is implemented with 16-bit variable instruction lengths (2 to 14 bytes) and permits register to register arithmetic and logic operations.

A linear address space of up to 16 Mbytes is possible.

Signed or unsigned multiply instruction (8 x 8, 16 x 16, or 32 x 32-bits)

Signed or unsigned divide instruction (16 8, 16 16, 32 16, 32 32-bits)

Special EEPROM write instruction and high-speed block transfer instruction

Memory: the TOE has a memory mapped architecture and allows the EEPROM to be used for both data and program storage. There is a special block of RAM dedicated for coprocessor use, that can be used as normal RAM when not required by the coprocessor.

ROM

RAM

EEPROM o on-chip charge pump and independent oscillator o special write instruction, and interrupt generation on writing o page write/erase o individual page protection

RNG: this can generate 64-bit random numbers. Using the RNG enables a unique value to be generated inside the chip, which improves the system security. Note that the RNG generates a

64-bit (16-bit × 4) random number at one time, but it is provided to the user of the TOE by 16 bits.

DES coprocessor: this hardware coprocessor can be used to provide either DES or triple-DES functions to the users’ software with very little software overhead. Countermeasures against information leakage have been integrated into the coprocessor unit to make it highly resistant to such attacks with minimal software overheads or execution time penalties. These countermeasures are always active and make no additional requirements on Smartcard

Embedded Software.

Interval timer 1: this counter operates in synchronisation with TCK. The first interval interrupt after start-up of this timer is issued in arbitrary terms, and from the second time onwards, interval interrupts are issued periodically in a specified term.

Revision 2.0, 23 February, 2007 Page 5 of 59

HD65256D Security Target

– Public Version

HD65256D-CC-ST-0002

Interval timer 2: this counter operates with eight types of input clocks that are synchronous with SCK, and issue interval interrupts periodically in arbitrary terms.

Interval timer 3: this counter operates in synchronisation with SCK, and issues interval interrupts in arbitrary but in ten minutes terms.

WDT: the watchdog timer is a powerful tool to help the user software detect and respond to unauthorised program execution. Use of the WDT is optional and should be selected using

[OPT].

FMU: this memory management function monitors memory access permissions for the user software and enables the limiting of program execution from RAM and EEPROM.

CRC coprocessor: CRC (Cyclic Redundancy Check) coprocessor generates codes for detecting errors in data blocks. The CRC codes are created using a generator polynomial CRC-

CCITT(X

16

+X

12

+X

5

+X

0

).

LSERB: half-duplex serial interfaces synchronous with SCK.

LUART: half-duplex asynchronous mode interfaces. There are two 256B buffers; one for sending and another for receiving.

LNRRT: half-duplex serial interfaces synchronous with TCK. These interfaces are available for transmissions using NRZ coding. There are two 256B buffer; one for sending and another for receiving.

System control logic: System control logic generates a signal to control the interface between the CPU subsystem and each other subsystem.

Security logic: the IC incorporates specialised security logic to help to ensure the correct operation of the TOE.

Some security features, such as FMU, allow the Smartcard Embedded Software to determine the events to be monitored and the actions to be taken; many of them however are independent of software and are designed to operate automatically when required, to return the TOE to a secure state. The IC also provides protection features to resist leakage attacks.

Physical security of the IC is enhanced by the presence of shielding over critical areas, and by the use of design techniques that obscure the function and operation of the physical layout.

Full details of the operation of the chip and guidance for its use are given in [HM], [OPT],

[EEPOPT], and [UGM1].

2.1.2 Softwar e

The TOE includes the following software:

IC Dedicated Test Software:

The IC Dedicated Test Software is integrated into the TOE hardware. It is used for mode transition and testing during IC production, and is not available to users.

Revision 2.0, 23 February, 2007 Page 6 of 59

HD65256D Security Target

– Public Version

The RNG On-line Test Software:

HD65256D-CC-ST-0002

The RNG On-line Test Software is provided to perform the on-line test for randomness, as required in [AIS31]. To enable users to deploy the software as necessary, this software is supplied as a listing in [UGM1]. Note that the use of this software is part of the intended method of use of the TOE under certain conditions, and it is therefore part of the evaluated configuration.

All other Smartcard Embedded Software (e.g. an operating system) is outside the scope of the

TOE. The Smartcard Embedded Software is supplied to Renesas by the customer in a secure manner, and is then protected by Renesas’ secure production environment.

2.1.3 Documents

The TOE Hardware Manual [HM] is supplied as the basic reference for users who are developing Smartcard Embedded Software. Guidance for the secure use of the HD65256D in applications is given in the User Guidance Manual (for Software Developer) [UGM1]. There is another guidance manual which is intended for users of the TOE [UGM2]. Options and contents of the identification data stored in the EEPROM are described in [OPT] and [EEPOPT].

2.2 TOE Intended Usage

The TOE is intended for use in a range of high security applications, including high speed secure authentication, data encryption or electronic signature. Examples include: e-money and e-ticket.

2.3 TOE Lifecycle

The design and manufacturing lifecycle for the TOE is shown in Figure 2-2 (and in section 8.1.1 of [BSI-PP-0002]). The TOE can be delivered only at the end of phase 4, as shown in the figure.

TOE lifecycle in this ST is augmented from the basic lifecycle of smartcard IC defined in [BSI-

PP-0002]; a part of phase 5 is included in the TOE lifecycle.

Revision 2.0, 23 February, 2007 Page 7 of 59

HD65256D Security Target

– Public Version

Initial p er son alisation r eq uir emen ts

In itial per sonalisation command an d d ata

Pr e-per sonalisation r equir emen ts

E mb edd ed Softwar e

Pr e-per sonalisation data

Smar tcar d

E mb edd ed Softwar e

IC sensitive in for mation , softwar e, and tools

HD65256D-CC-ST-0002

IC Design

P hase 1

IC Ded icated Softwar e

Smar tcar d IC

Database Constr uction

IC Phot omask

Fabr ication

P hase 2

Pr e-per sonalisation r equir emen ts

IC M anufactur ing

IC T esting &

Pr e-per son alisation

P hase 3

In itial per sonalisation r equir ements

IC Pack agin g

Testing

Smar tcar d Finishin g Pr ocess

Testing

Per son alisation

Testing

P hase 4

P hase 5

P hase 6

Smar tcar d Pr od uct En d-Usage

P hase 7

En d of L ife Pr ocess

Figur e 2-2: Design and Manufacturing Lifecycle

The stages shown are as listed below. This Security Target addresses phases 2, 3 and 4 in Figure

2-2. In addition, Initial personalisation related process in phase 5 is also covered.

Revision 2.0, 23 February, 2007 Page 8 of 59

HD65256D Security Target

– Public Version

HD65256D-CC-ST-0002

Phase 1: Smartcard Embedded Software development – this phase is outside the scope of the

TOE, but the results of the software development are inputs to the manufacture of a customerspecific instance of the TOE. Renesas deliver information about the TOE (such as [HM]) to the embedded software developer to enable the Smartcard Embedded Software to be written.

Development tools (such as emulators) and IC samples are also available to developers.

Information and tools are released only under Non-Disclosure Agreement to ensure their distribution is controlled and limited (this ensures, for example, secure disposal of scrap).

The embedded software for incorporation in the ROM mask is sent via a secure delivery method from the software developer to Renesas, and its secure handling is then ensured by

Renesas. Similarly, pre-personalisation data is sent by a secure route to Renesas for injection during the manufacturing stage. Injection of data is described further in section 2.4.2. Secure receipt and handling of this data by Renesas is included within the scope of this security target.

Phase 2: IC design, IC Dedicated Test Software – this includes system design through logic, circuit and layout design. The Dedicated Test Software is also developed in this phase, to enable testing of the IC at various phases of its manufacture. The Smartcard Embedded

Software is received from phase 1.

The security of the development environments for the IC and its dedicated software, along with the secure handling of masks are primary concerns of this security target.

Phase 3: Mask fabrication and IC wafer manufacturing – The masks used to manufacture the various IC layers are created from the layout design during phase 2; ROM masks for the

Smartcard Embedded Software in a particular instance of the TOE are fabricated after receipt of the software in phase 2. Also, in this phase, wafers containing TOE dies with Smartcard

Embedded Software are produced. At the end of this process each die is tested and has its pre-personalisation data injected into EEPROM (see section 2.4.2).

The secure fabrication and handling of masks, and the security of manufacture, including handling of masks, test software, and pre-personalisation data are primary concerns of this security target.

Phase 4: IC Packaging – each wafer is cut into individual dies and its protective packaging applied, along with its contacts. The resulting module is then tested in Test Mode to ensure correct operation, after which it is set to User Mode.

Phase 5: Smartcard finishing process – there are two major processes in phase 5. In the first process, the final testing of the Smartcard Embedded Software and the Initial Personalisation are performed. In the Initial Personalisation, the Smartcard Embedded Software is set to User

Mode to make the TOE ready for Personalisation. In the second process, the TOE is loaded into a handset. This Security Target includes the Initial Personalisation in the first process as a part of the life cycle of the TOE.

The TOE is delivered at a point between the Initial Personalisation and TOE loading to handsets.

Phases 6-7: Smartcard personalisation and end-usage – these stages, and their security features, are determined by the customer, and are outside the scope of this security target.

Revision 2.0, 23 February, 2007 Page 9 of 59

HD65256D Security Target

– Public Version

2.3.1 Test and User Modes

HD65256D-CC-ST-0002

During manufacturing and production (phases 2-4), the chip makes some mode transitions which affect the interface presented. These modes are as follows:

Test mode makes the IC Dedicated Test Software available, which is used to ensure that only correctly working ICs are delivered.

User mode makes the IC Dedicated Test Software unavailable and the TOE now provides only the functionality described in [HM]. The software interface presented will be determined by the Smartcard Embedded Software.

As explained under the individual lifecycle phases above, the chip is always in test mode in phases 2 and 3. Then the chip will be in the constrained test mode during phase 4, making a limited set of test functions available to test the correct operation of modules after packaging.

However, the TOE is always in User Mode after being assembled into a module format, and the transition from User Mode to Test Mode is designed to be very difficult.

2.3.2 TOE Deliver y

As noted above, the TOE is delivered after the Initial Personalisation in phase 5. The chip will be delivered in User Mode, and Renesas will apply secure delivery procedures for the transport of the TOE from Renesas premises.

2.4 TOE Envir onments

2.4.1 Development Environment

Renesas’ development environment for the TOE has implemented security measures specifically to ensure the security of the TOE and of Smartcard Embedded Software and injection data used in manufacturing ICs for customers. As indicated in section 2.3, there are three areas of the development environment:

Design sites

Mask manufacture site

Manufacturing sites

These provide the following main security properties:

Design sites

Confidentiality and integrity of logical and physical design

Testing of TOE security functionality

Confidentiality and integrity of IC Dedicated Test Software

Confidentiality and integrity of customer ROM code, injection data and commands and data for initial personalisation (i.e. the Smartcard Embedded Software for an instance of the TOE)

Revision 2.0, 23 February, 2007 Page 10 of 59

HD65256D Security Target

– Public Version

Mask manufacture site

Confidentiality and integrity of customer ROM code and mask

Confidentiality and integrity of design and base masks

HD65256D-CC-ST-0002

Manufacturing sites

Confidentiality and integrity of base masks

Confidentiality and integrity of customer ROM mask

Confidentiality and integrity of test software

Confidentiality and integrity of injection data

Confidentiality and integrity of commands and data for initial personalisation

Production of authentic TOE ICs, correctly implementing the design and including the customer Smartcard Embedded Software in ROM.

Proper initial personalisation through secure and proper use of commands and data provided from customers for the initial personalisation.

Security issues for each of these areas are addressed by processes and procedures put in place by

Renesas and within the scope of evaluation. The security measures include IT security to protect information stored on Renesas computer systems, as well as physical security measures for secure storage to ensure that design and manufacturing information and objects are only accessible to authorised staff with a need to know the information. Renesas' integrated security concept (ISC) covers the entire development process, from specification, through design and implementation to manufacturing and shipping. ISC is implemented through the use of standards and procedures that form part of the quality system at the heart of Renesas' business.

The rigorous adoption and adherence to procedures, including those relating to security, is an integral part of the quality system at the heart of Renesas’ business.

The security of the IC Dedicated Test Software at design and manufacturing sites is ensured by the same level of security measures as for the hardware design. This ensures that only authorised persons have access to the software and its related information.

Smartcard Embedded Software is received from customers via a secure delivery procedure.

Once received by Renesas, this software is also handled with the same level of security as for design information. As a further measure, the group handling customer software is separate from the IC design team.

2.4.2 Injection of Manufacturing Identification and Secret Data

In general, although there will be a substantial amount of operating system and application software held in ROM, an IC will also require software to be added after it leaves the manufacturing environment. Operating system software may require additional parts or patches to be loaded, and increasingly applications are expected to be loaded and deleted after a smart card has been issued to users. In order to enable such addition (and deletion) of software to be done securely, there is a generic requirement for identification data and secret data, determined by the IC purchaser, to be injected during manufacture.

Revision 2.0, 23 February, 2007 Page 11 of 59

HD65256D Security Target

– Public Version

HD65256D-CC-ST-0002

The TOE supports this requirement by injecting identification data during the manufacturing process; this data uniquely identifies each IC. In addition, customers may choose to inject further data. The details of the data content and its location in memory are shown in [EEPOPT].

Revision 2.0, 23 February, 2007 Page 12 of 59

HD65256D Security Target

– Public Version

HD65256D-CC-ST-0002

3. TOE Secur ity Envir onment

3.1 Assets

This section defines the primary and secondary assets to be protected by the TOE. Section 3.1 of

[BSI-PP-0002] gives the assets relating to the threats, and these are summarised below.

The primary assets to be protected are classified as:

User Data – this includes injection/pre-personalisation data, data generated and managed by the Smartcard Embedded Software, and initial personalisation commands and data (subject to adequate protection by the software, see A.Key-Function, A.Plat-Appl and A.Resp-Appl in section 3.2)

Smartcard Embedded Software, comprising

Hard-coded Embedded Software – this is fixed and generally consists of parts or all of the operating system, and parts or all of a number of applications

Soft-coded Embedded Software – this may include parts of the operating system or applications.

Both of these types of asset need to have their confidentiality and integrity protected.

A further primary asset is:

Correct operation of the TOE (including its random number generator).

In particular this means that the Smartcard Embedded Software will be correctly executed, which includes the correct operation of the TOE’s functions.

Because random numbers are likely to be used by embedded software for generating cryptographic keys, another primary asset is:

the random numbers generated by the TOE

1

Secondary assets are critical information about the TOE, including logical design data, physical design data, IC Dedicated Test Software and TSF data.

In addition, the following will also contain information about the TOE.

Initialisation Data and Pre-personalisation Data, specific development aids, test and characterisation related data, material for software development support, and photomasks.

1

The confidentiality of random numbers is generally protected by embedded software (which is responsible for requesting random numbers). However, it is important that random numbers should not be subject to leakage (cf.

T.Leak-Inherent), because of their potential role in cryptographic key generation.

Page 13 of 59 Revision 2.0, 23 February, 2007

HD65256D Security Target

– Public Version

HD65256D-CC-ST-0002

Such information and the ability to perform manipulations assist in threatening the primary assets.

Assets relating specifically to the Organisational Security Policy P.Process-TOE and Assumption

A.Process-Card are given in section 3.1 of [BSI-PP-0002].

3.2 Assumptions

3.2.1 Assumptions from [BSI-PP-0002]

The following assumptions are made:

A.Process-Card Protection during Packaging, Finishing and Personalisation

It is assumed that security procedures are used by the recipient after delivery of the TOE by Renesas up to delivery to the end-user to maintain confidentiality and integrity of the TOE and of its manufacturing and test data (to prevent any possible copy, modification, retention, theft or unauthorised use).

The exact requirements of this assumption will depend on the Smartcard Embedded Software.

This means that the phases after TOE Delivery (refer to section 2.3) are assumed to be protected appropriately. For a preliminary list of assets to be protected, see section 3.1 of [BSI-PP-0002].

A.Plat-Appl Usage of Hardware Platform

The Smartcard Embedded Software is designed so that the requirements from the following documents are met:

(i) The TOE hardware manual [HM], user guidance manual [UGM1], and the hardware application notes

(ii) Findings of the TOE evaluation reports relevant for the Smartcard

Embedded Software.

A.Resp-Appl Treatment of User Data

All User Data is owned by Smartcard Embedded Software. Therefore, it is assumed that security relevant User Data (especially cryptographic keys) are treated by the Smartcard Embedded Software as defined for the specific application context.

This assumption requires that the Smartcard Embedded Software define and positively manage its security relevant User Data, in the manner required by the application context. Without this, the protection provided by the TOE itself may be of no use if the Smartcard Embedded Software itself allows data to be compromised.

Examples of embedded software security concerns are given in section 8.2 of [BSI-PP-0002].

Revision 2.0, 23 February, 2007 Page 14 of 59

HD65256D Security Target

– Public Version

3.2.2 Assumptions from [PA]

A.Key-Function Usage of Key-dependent Functions

HD65256D-CC-ST-0002

Key-dependent functions (if any) shall be implemented in the Smartcard

Embedded Software in a way that they are not susceptible to leakage attacks (as described under T.Leak-Inherent and T.Leak-Forced).

Note that here the routines which may compromise keys when being executed are part of the Smartcard Embedded Software. In contrast to this the threats T.Leak-Inherent and T.Leak-Forced address (i) the cryptographic routines which are part of the TOE and (ii) the processing of

User Data including cryptographic keys.

Note here that the functions considered in this assumption are part of the Smartcard Embedded

Software; T.Leak-Inherent and T.Leak-Forced address the cryptographic functions that are part of the hardware.

To assist embedded software developers to implement leak-resistant code, guidance on secure software implementation is given in [UGM1].

3.2.3 Other Assumptions

A variety of keys and other security-critical data may be injected for use by Smartcard

Embedded Software. These may include shared private keys, public/private key pairs, etc. This information could contribute to a cloning attack, or to breaking the security of an instance of the

TOE (e.g. by compromising its keys). The integrity of this data is also vital to ensuring the security of the TOE (e.g. preventing unauthorised changes to mask code, IC design or keys). All data supplied for injection/pre-personalisation is assumed to be supported off-card in a secure manner:

A.InjDatSupp Injected Data Support

Data for injection/pre-personalisation will be supplied from the various bodies controlling the operations of the system in which the TOE is functioning, based on [EEPOPT]. It is assumed that the generation, distribution, maintenance, and destruction of this data is adequately secure.

3.3 Thr eats

3.3.1 Thr eats Defined in [BSI-PP-0002]

This section adopts the threats to ICs defined in section 3.3 of [BSI-PP-0002].

The TOE has the following high-level security concerns, as in section 3.3 of [BSI-PP-0002]:

SC1 manipulation of User Data and of the Smartcard Embedded Software (while being executed/processed and while being stored in the TOE’s memories).

Revision 2.0, 23 February, 2007 Page 15 of 59

HD65256D Security Target

– Public Version

HD65256D-CC-ST-0002

SC2 disclosure of User Data and of the Smartcard Embedded Software (while being processed and while being stored in the TOE’s memories).

SC3 deficiency of random numbers.

These high-level security concerns are refined below by defining specific threats. Note that manipulation of the TOE is only a means to threaten User Data or the Smartcard Embedded

Software and does not in itself represent a successful attack.

These security concerns are derived from considering the end-usage phase (phase 7) since

Phase 1 and phases from TOE Delivery up to the end of phase 6 are covered by assumptions, and

The development and production environment starting with phase 2 and ending with TOE

Delivery are covered by an organisational security policy

3.3.1.1 Thr eats Derived from SC1-SC3

See section 3.3 of [BSI-PP-0002], and the example attack scenarios in section 8.3 of [BSI-PP-

0002]. For completeness, the threats are summarised below.

T.Leak-Inherent Inherent Information Leakage

An attacker may exploit information which is leaked from the TOE during usage of the Smartcard in order to disclose confidential data

(User Data or TSF Data).

No direct contact with the Smartcard internals is required here.

Leakage may occur through emanations, variations in power consumption, I/O characteristics, clock frequency, or by changes in processing time requirements.

Differential Power Analysis (DPA) is an example of an attack based on the inherent leakage threat.

T.Phys-Probing Physical Probing

An attacker may perform physical probing of the TOE in order to:

(i) disclose User Data

(ii) disclose/reconstruct the Smartcard Embedded Software

(iii) disclose other critical operational information especially TSF data.

Physical probing requires direct contact with the TOE circuit structures. Before attacks based on this threat can be mounted, hardware security mechanisms and layout characteristics need to be identified. Determination of software design, including treatment of User Data, may also be a pre-requisite.

Revision 2.0, 23 February, 2007 Page 16 of 59

HD65256D Security Target

– Public Version

T.Phys-Manipulation Physical Manipulation

HD65256D-CC-ST-0002

An attacker may physically modify the Smartcard in order to

(i) modify security features or functions of the TOE

(ii) modify security functions of the Smartcard Embedded

Software

(iii) modify User Data.

Modification may be achieved through techniques commonly employed in IC failure analysis and IC reverse-engineering. The modification may result in the deactivation of a security function. As with T.Phys-Probing, before attacks based on this threat can be mounted, hardware security mechanisms and layout characteristics need to be identified. Determination of software design including treatment of User Data may be a pre-requisite. Changes to circuitry or data can be permanent or temporary.

In contrast to malfunctions (see T.Malfunction), the attacker needs to gather significant knowledge about the TOE’s internal construction in order to launch a manipulation attack.

T.Malfunction Malfunction due to Environmental Stress

An attacker may cause a malfunction of the TSF or of the Smartcard

Embedded Software by applying environmental stress in order to

(i) deactivate or modify security features or functions of the TOE

(ii) deactivate or modify security functions of the Smartcard

Embedded Software.

This may be achieved by operating the IC outside its normal operating conditions.

Unlike T.Phys-Manipulation, attacks based on environmental stress can be launched without significant knowledge of the IC’s internal construction on the part of the attacker. However, to exploit the attack, the attacker needs information about the functional operation.

T.Leak-For ced Forced Information Leakage

An attacker may exploit information which is leaked from the TOE during usage of the smartcard in order to disclose confidential data

(User Data or TSF Data), even if the information leakage is not inherent but caused by the attacker.

This threat pertains to attacks where methods described in

“Malfunction due to Environmental Stress” (T.Malfunction) and/or

“Physical Manipulation” (T.Phys-Manipulation) are used to cause leakage from signals which normally do not contain significant information about secrets.

Differential Fault Analysis (DFA) is an example of an attack based on the forced leakage threat.

Revision 2.0, 23 February, 2007 Page 17 of 59

HD65256D Security Target

– Public Version

T.Abuse-Func Abuse of Functionality

HD65256D-CC-ST-0002

An attacker may use functions of the TOE which may not be used after TOE Delivery in order to

(i) disclose or manipulate User Data

(ii) manipulate (explore, bypass, deactivate or change) security features or functions of the TOE or of the Smartcard

Embedded Software

(iii) enable an attack.

For the TOE, T.Abuse-Func concerns the threat of unauthorised access to the IC Dedicated Test

Software, which is rendered inaccessible by placing the IC into User Mode before TOE Delivery

(see section 2.3).

T.RND Deficiency of Random Numbers

An attacker may predict or obtain information about random numbers generated by the TOE, for instance because of a lack of entropy of the random numbers provided.

An attacker may gather information about the random numbers produced.

Malfunctions or premature ageing are also considered as they may assist in giving the attacker information about random numbers.

Attacks on random number generation are significant because the random numbers generated may be used as secrets - e.g. to generate cryptographic keys.

Under the threat T.RND, the attacker is assumed to take advantage of statistical properties of the random numbers generated by the TOE without specific knowledge about the RNG itself.

3.3.2 Other Threats

The TOE makes available facilities that are useful for embedded software to use in addressing the threats that it may face. This introduces an additional high-level security concern for the

TOE:

SC4 attacks on the Smartcard Embedded Software may be made, and the software may not be able to detect or respond to the attacks.

T.NoSWDetect Inability of the TOE to detect an attack

In a multi-layered or multi-application software environment, there may be attacks on one part of the Smartcard Embedded Software arising from another part. Smartcard Embedded Software execution may also be attacked via various means, with the intention of corrupting software execution in a specific or random way. If the

Revision 2.0, 23 February, 2007 Page 18 of 59

HD65256D Security Target

– Public Version

HD65256D-CC-ST-0002

TOE cannot detect such attacks, then it cannot apply any countermeasures to protect itself.

The TOE is concerned in particular to detect the following:

(i) Attempts to access memory outside an area defined for the software being executed

(ii) Attempts to make an illegal access

(iii) Attempts to execute code from a type of memory not permitted by the software environment

2

(iv) Attempts to write to EEPROM addresses containing data that should not be changed

(v) Attempts to execute an illegal instruction code

(vi) Attempts to alter registers controlling the operation of the TOE.

For the purposes of this threat, an illegal access is one that is marked “ ” in the tables titled

“Access” in the TOE memory map (section 3 of [HM]). In addition, among the accesses marked

“○” in the tables, if a type of access allowed is noted under the circle, an access other than the allowed type of access is also an illegal access.

This threat applies whether the “attack” is deliberate or due to errors, but all the attacks covered are launched from software. Inducing errors by external means, as covered in T.Phys-

Manipulation, may also give rise to the same sort of error conditions as listed for T.NoSWDetect.

T.NoSWResponse Inability of Smartcard Embedded Software to respond to an attack

If Smartcard Embedded Software cannot detect a potential attack, or other dangerous condition, and has no ability to take action when such a condition is detected then there is a danger that it will not be able to prevent the attack continuing.

This threat does not address the particular details of individual attacks, but recognises that

Smartcard Embedded Software may make checks on its own state to enhance protection against a variety of attacks (including those aimed at inducing errors by software or external means).

For such checks to be useful, there must also be ways for the software to respond to the attack

(e.g. by preventing further processing).

2

The “software environment” is a term used to capture the definition of acceptable memory use for the software system using the TOE. This would usually be at the level of operating system software.

Page 19 of 59 Revision 2.0, 23 February, 2007

HD65256D Security Target

– Public Version

3.4 Or ganisational Secur ity Policies

HD65256D-CC-ST-0002

3.4.1 Policy Requirement from [BSI-PP-0002]

The following policy requirement is taken from section 3.4 of [BSI-PP-0002].

P.Process-TOE Protection during TOE Development and Production

The TOE Manufacturer must ensure that the development and production of the Smartcard Integrated Circuit (Phase 2 up to TOE Delivery) is secure so that no information is unintentionally made available for the operational phase of the TOE. For example, the confidentiality and integrity of design information and test data shall be guaranteed; access to samples, development tools and other material shall be restricted to authorised persons only; scrap will be destroyed etc. This not only pertains to the

TOE but also to all information and material exchanged with the developer of the Smartcard Embedded Software and therefore especially to the

Smartcard Embedded Software itself. This includes the delivery

(exchange) procedures for Phase 1 and the Phases after TOE Delivery as far as they can be controlled by the TOE Manufacturer.

An accurate identification must be established for the TOE. This requires that each instantiation of the TOE carries this unique identification.

Assets relating specifically to P.Process-TOE are given in section 3.1 of [BSI-PP-0002].

Renesas implement the security measures to satisfy this policy requirement, and these are assessed as part of evaluation and certification against this ST. However, since they are not directly relevant to users of the TOE, the detailed measures and processes that implement the policy are not given here.

Note that the inclusion of identification information in EEPROM is described in more detail in section 2.4.2. This part of the policy establishes a basis for evaluation and security of software running on the chip, by ensuring that a TOE can be identified. Note that procedural measures

(including Renesas’ secure delivery procedures) will generally be required to ensure that TOE

ICs are genuine, unless the Smartcard Embedded Software contains functionality to authenticate the IC

3

.

P.Process-TOE covers identification of hard-coded Embedded Software (via identification of the

ROM mask); soft-coded Embedded Software will generally need to provide its own identification.

3.4.2 Policy Requirement from [PA]

As an additional policy, the TOE provides specific security functionality which can be used by the Smartcard Embedded Software for cryptographic algorithm implementation. The policy

3

For example, a hash or digital signature over a known area of memory might be provided by software.

Page 20 of 59 Revision 2.0, 23 February, 2007

HD65256D Security Target

– Public Version

HD65256D-CC-ST-0002

P.Add-Functions is therefore adopted from [PA]. In the following policy, specific security functionality is listed which is not derived from threats identified for the TOE’s environment because it can only be decided in the context of the smartcard application, against which threats the Smartcard Embedded Software will use the specific security functionality.

P.Add-Functions Additional Specific Security Functionality

The TOE shall provide the following specific security functionality to the

Smartcard Embedded Software:

Data Encryption Standard (DES)

Revision 2.0, 23 February, 2007 Page 21 of 59

HD65256D Security Target

– Public Version

4. Secur ity Objectives

4.1 TOE Secur ity Objectives

HD65256D-CC-ST-0002

4.1.1 Objectives from [BSI-PP-0002]

The TOE shares the following high-level security considerations from section 4.1 of [BSI-PP-

0002]:

SG1 maintain the integrity of User Data and of the Smartcard Embedded Software (when being executed/processed and when being stored in the TOE’s memories).

SG2 maintain the confidentiality of User Data and of the Smartcard Embedded Software

(when being processed and when being stored in the TOE’s memories).

SG3 provide random numbers.

These high-level security considerations are refined below by defining security objectives as required by the Common Criteria. Note that maintaining the integrity of the TOE is a means to achieve these objectives.

O.Leak-Inherent Protection against Inherent Information Leakage

The TOE must provide protection against disclosure of confidential data

(User Data or TSF Data) stored and/or processed in the smartcard IC by measurement and analysis of

The shape and amplitude of signals (for example on the power, clock, or I/O lines)

the time between events found by measuring signals (for example on the power, clock, or I/O lines).

This objective pertains to measurements with subsequent complex signal processing whereas

O.Phys-Probing is about direct measurements on elements on the chip surface.

Note that this objective relates to security features provided by the TOE itself, and Smartcard

Embedded Software should ensure that the security features are appropriately used in conjunction with any additional leakage countermeasures implemented in software (cf. A.Plat-

Appl and A.Resp-Appl in section 3.2.1).

O.Phys-Probing Protection against Physical Probing

The TOE must provide protection against disclosure of User Data, against the disclosure/reconstruction of the Smartcard Embedded Software, and against the disclosure of other critical operational information. This includes protection against

measuring through galvanic contacts, which is direct physical probing on the chip’s surface other than on pads being bonded (using standard tools for measuring voltage and current)

Revision 2.0, 23 February, 2007 Page 22 of 59

HD65256D Security Target

– Public Version

HD65256D-CC-ST-0002

measuring not using galvanic contacts but other types of physical interaction between charges (using tools used in solid-state physics research and IC failure analysis).

The TOE must be designed and fabricated so that it requires a high combination of complex equipment, knowledge, skill, and time to be able to derive detailed design information or other information which could be used to compromise security through such a physical attack.

O.Phys-Probing assumes that the attacker has first performed reverse-engineering to understand the design and its properties and functions.

O.Malfunction Protection against Malfunctions

The TOE must ensure its correct operation.

The TOE must prevent itself from being operated outside the normal operating conditions where reliability and secure operation has not been proven or tested. This is to prevent errors. The environmental conditions may include voltage, clock frequency, temperature, or external energy fields.

An attacker may also attempt to cause the chip to malfunction by using a direct galvanic contact on elements on the chip surface. This is considered as being a manipulation (see

O.Phys-Manipulation) provided that detailed knowledge about the TOE’s internal construction is required and the attack is performed in a controlled manner.

O.Phys-Manipulation Protection against Physical Manipulation

The TOE must provide protection against physical manipulation of the

TOE (including its software and TSF data), the Smartcard Embedded

Software and User Data. This includes protection against

reverse-engineering (understanding the design and its properties and functions)

manipulation of the hardware and any data

controlled manipulation of memory contents (User Data).

O.Leak-Forced

The TOE must be designed and fabricated so that it requires a high combination of complex equipment, knowledge, skill, and time to be able to derive detailed design information or other information which could be used to compromise security through such a physical attack.

Protection against Forced Information Leakage

The Smartcard must be protected against disclosure of confidential data

(User Data or TSF data) processed in the Card (using methods as described under O.Leak-Inherent) even if the information leakage is not inherent but caused by the attacker

Revision 2.0, 23 February, 2007 Page 23 of 59

HD65256D Security Target

– Public Version

HD65256D-CC-ST-0002

by forcing a malfunction (cf. O.Malfunction) and/or

by a physical manipulation (cf. O.Phys-Manipulation).

This objective includes resistance to attacks where T.Phys-Manipulation and T.Leak-Inherent are combined.

O.Abuse-Func Protection against Abuse of Functionality

The TOE must prevent abuse of IC Dedicated Test Software (which may not be used after TOE Delivery) that would

(i) disclose critical User Data

(ii) manipulate critical User Data of the Smartcard Embedded Software

(iii) manipulate Soft-coded Smartcard Embedded Software

(iv) bypass, deactivate, change or explore security features or functions of the TOE.

O.Identification TOE Identification

The TOE must provide a means to store Initialisation Data and Prepersonalisation Data in its non-volatile memory. The Initialisation Data

(or parts of them) are used for TOE identification.

The TOE identification data is described in section 2.4.2.

O.RND Random Numbers

The TOE will ensure the cryptographic quality of random number generation. For instance, random numbers shall not be predictable and shall have sufficient entropy.

The TOE will ensure that no information about the produced random numbers is available to an attacker since they might be used, for instance, to generate cryptographic keys.

4.1.2 Objectives Based on [PA]

This section includes an objective for the TOE to provide a DES function, which is based on

O.Add-Functions in [PA].

O.Add-Functions Additional Specific Security Functionality

The TOE must provide the following specific security functionality to the

Smartcard Embedded Software:

Data Encryption Standard (DES)

Revision 2.0, 23 February, 2007 Page 24 of 59

HD65256D Security Target

– Public Version

HD65256D-CC-ST-0002

Note that to achieve an adequate strength of function for an application context, Smartcard

Embedded Software may require use of triple-DES. The TOE Hardware enables this using repeated application of the DES coprocessor – this is discussed in section 16.3.1 of [HM] and in section 5.1.2.1 of this document.

4.1.3 Other Objectives

The TOE offers additional facilities to protect embedded software from corrupted, erroneous, or malicious software. The same facilities may protect from some results of attempts at physical manipulation (cf. O.Phys-Manipulation).

A further high-level security consideration is therefore derived from SC4 in section 3.3.2.

SG4 software should be given the ability to detect and respond to attacks.

This leads to objectives that

O.SWDetect Detection of potential attacks by the TOE

The following conditions shall be detected as an aid to identifying potential attacks:

(i) Attempts to access memory outside an area defined for the software being executed

(ii) Attempts to make an illegal access

(iii) Attempts to execute code from a type of memory not permitted by the software environment

4

(iv) Attempts to write to EEPROM addresses containing data that should not be changed

(v) Attempts to execute an illegal instruction code

(vi) Attempts to alter registers controlling the operation of the TOE.

The Smartcard Embedded Software itself will determine the memory area for (i), the types of memory permitted for (iii), and the protected EEPROM addressed for (iv).

O.SWResponse Response to potential attacks by Smartcard Embedded Software

The TOE shall allow Smartcard Embedded Software to:

(i) periodically interrupt processing to execute a known piece of

Smartcard Embedded Software

4

The “software environment” is a term used to capture the definition of acceptable memory use for the software system using the TOE. This would usually be at the level of operating system software.

Page 25 of 59 Revision 2.0, 23 February, 2007

HD65256D Security Target

– Public Version

(ii) cause the processor to enter the reset state.

HD65256D-CC-ST-0002

Executing a known piece of embedded software periodically gives embedded software the ability to check the execution state for any conditions that it wishes to monitor (in addition to those indicated under O.SWDetect above) and stop execution, or take some other action, if it detects a potential attack or other dangerous condition.

4.2 Envir onment Secur ity Objectives

4.2.1

Phase 1

Environment Security Objectives from [BSI-PP-0002]

OE.Plat-Appl Usage of Hardware Platform

The Smartcard Embedded Software shall be designed so that the requirements from the following documents are met:

(i) The TOE hardware manual [HM], user guidance manual [UGM1], and the TOE application notes.

(ii) Findings of the TOE evaluation reports relevant to the Smartcard

Embedded Software.

Because the TOE implements additional specific security functionality (as in O.Add-Functions),

OE.Plat-Appl covers the use of these functions by Smartcard Embedded Software as follows:

OE.Resp-Appl

If required, the Smartcard Embedded Software shall use these cryptographic services of the TOE and their interface as specified. When key-dependent functions implemented in the Smartcard Embedded

Software are just being executed, the Smartcard Embedded Software must provide protection against disclosure of confidential data (User Data) stored and/or processed in the TOE by using the methods described under

“Inherent Information Leakage (T.Leak-Inherent)” and “Forced

Information Leakage (T.Leak-Forced)“.

Treatment of User Data

Security relevant User Data (especially cryptographic keys) are treated by the Smartcard Embedded Software as required by the security needs of the specific application context.

Because the TOE implements additional specific security functionality (as in O.Add-Functions),

OE.Resp-Appl covers the use of these functions by Smartcard Embedded Software as follows:

By definition cipher or plain text data and cryptographic keys are User

Data. The Smartcard Embedded Software shall treat these data appropriately, use only proper secret keys (chosen from a large key space) as input for the cryptographic function of the TOE and use keys and functions appropriately in order to ensure the strength of cryptographic operation.

Revision 2.0, 23 February, 2007 Page 26 of 59

HD65256D Security Target

– Public Version

HD65256D-CC-ST-0002

This means that keys are treated as confidential as soon as they are generated. The keys must be unique with a very high probability, as well as cryptographically strong. For example, it must be ensured that it is not possible to derive the private key from a public key if asymmetric algorithms are used. If keys are imported into the TOE and/or derived from other keys, quality and confidentiality must be maintained. This implies that appropriate key management has to be realised in the environment.

From Phase 2 until TOE Delivery

OE.Process-TOE Protection during TOE Development and Production

The TOE Manufacturer must ensure that the development and production of the Smartcard Integrated Circuit (Phases 2 and 3 up to TOE Delivery) is secure so that no information is unintentionally made available for the operational phase of the TOE. For example, the confidentiality and integrity of design information and test data must be guaranteed, access to samples, development tools and other material must be restricted to authorised persons only, scrap must be destroyed. This not only pertains to the TOE but also to all information and material exchanged with the developer of the Smartcard Embedded Software and therefore especially to the Smartcard Embedded Software itself. This includes the delivery

(exchange) procedures for Phase 1 and the Phases after TOE Delivery as far as they can be controlled by the TOE Manufacturer.

An accurate identification must be established for the TOE. This requires that each instantiation of the TOE carries this unique identification. In order to make this practical, electronic identification shall be possible.

Assets relating specifically to the Organisational Security Policy P.Process-TOE (which is the source of this objective) are given in section 3.1 of [BSI-PP-0002].

From TOE Delivery until the beginning of Phase 7

OE.Process-Card Protection during Packaging, Finishing and Personalisation

Security procedures shall be used after TOE Delivery up to delivery to the end-user to maintain confidentiality and integrity of the TOE and of its manufacturing and test data (to prevent any possible copy, modification, retention, theft or unauthorised use).

This means that Phases after TOE Delivery up to the end of Phase 6 must be protected appropriately.

Assets relating specifically to the assumption A.Process-Card (which is the source of this objective) are given in section 3.1 of [BSI-PP-0002].

The precise nature of the protection required will depend on the application context.

Revision 2.0, 23 February, 2007 Page 27 of 59

HD65256D Security Target

– Public Version

4.2.2 Other Environment Security Objectives

HD65256D-CC-ST-0002

For injected/pre-personalisation data, the sources and holders of the data need to support its security requirements.

OE.InjDatSupp Injected Data Support

All data for injections/pre-personalisation shall be generated, distributed, maintained and destroyed in an adequately secure fashion. In general, the data shall be protected for both confidentiality and integrity.

Renesas ensures a secure interface with suppliers of this data by using the injection approach in section 2.4.2. Transmission of data to Renesas is secured by a variety of measures dependent on the transmission medium (e.g. ROM data may be sent by encrypted e-mail). The data is securely stored within the Renesas environment according to the medium.

Revision 2.0, 23 February, 2007 Page 28 of 59

HD65256D Security Target

– Public Version

HD65256D-CC-ST-0002

5. IT Secur ity Requir ements

5.1 TOE Secur ity Requir ements

The functional requirements for the TOE come from 3 sources:

[BSI-PP-0002]

These SFRs cover the core smart card IC requirements:

operating state – FRU_FLT.2 describes the usual operating conditions and requires the TOE to maintain a secure state; FPT_FLS.1 requires a secure response to exceptional operating conditions; FPT_SEP.1 requires the TOE to ensure that the secure responses to operating conditions are independent of software (since, for example, some software could be malicious)

controls over IC Dedicated Test Software – FMT_LIM.1 and

FMT_LIM.2 require that the use of IC Dedicated Test Software for manufacturing tests must not allow security to be compromised after

TOE Delivery

storage of identification/pre-personalisation data – FAU_SAS.1 requires that the TOE be capable of storing such data

protection against physical attacks – FPT_PHP.3 requires the TOE to be protected against physical tampering attacks

Protection against leakage – FDP_ITT.1 and FPT_ITT.1 require protection of data against leakage as it moves between components on the IC, and FDP_IFC.1 provides the policy of protection for data

Random number generation – FCS_RND.1 requires generation of good quality random numbers

[PA]

This SFR covers DES cryptographic requirements.

DES – FCS_COP.1 requires the implementation of DES in ECB mode

TOE features

Some SFRs introduced from [BSI-PP-0002] are given a wider scope to reflect additional security features of the TOE and functions which support secure features in embedded software:

Page 29 of 59 Revision 2.0, 23 February, 2007

HD65256D Security Target

– Public Version

HD65256D-CC-ST-0002

Additional failure detection – the scope of FPT_FLS.1 includes additional software failure conditions trapped by the TOE support to embedded software to run tests at certain points during execution

(enabling measures such as state integrity tests) and the ability of embedded software to cause a hardware reset (this is covered under

FPT_FLS.1 in section 5.1.1.1).

Controlled writes – FDP_ACC.1 [CRP] and FDP_ACF.1 [CRP] are added to represent the way in which some registers are protected against changes other than from embedded software executing in ROM;

FDP_ACC.1 [WPP] and FDP_ACF.1 [CRP] specify the ability to prevent writing to chosen EEPROM pages.

Note that all SFRs are drawn from [CC/2] except for FCS_RND.1, FMT_LIM.1 & 2, and

FAU_SAS.1, which are all defined in section 8 of [BSI-PP-0002].

5.1.1 TOE Security Functional Requir ements fr om [BSI-PP-0002]

In the specifications of SFRs listed below, ‘Refinement’ sections are taken from [BSI-PP-0002];

‘Application Notes’ add information specific to the TOE.

5.1.1.1 Operating Conditions

The TOE implements a pair of security functional requirements that ensure it operates within conditions under which it can maintain a secure state. This is represented in [BSI-PP-0002, fig

14], reproduced below:

Failure with preservation of secure state (FPT_FLS.1) max.

Limited fault tolerance

(FRU_FLT.2)

Technical limits without reduction due to FPT_FLS.1

min.

Usable limits of the product as enforced due to FPT_FLS.1

min.

max.

operating conditions

Figur e 5-1: Paradigm Regarding Operating Conditions

Erroneous software conditions (some of which could arise from corruptions due to operating conditions) are dealt with under FPT_FLS.1.

Revision 2.0, 23 February, 2007 Page 30 of 59

HD65256D Security Target

– Public Version

FRU_FLT.2 Limited fault tolerance

Hierarchical to: FRU_FLT.1

HD65256D-CC-ST-0002

FRU_FLT.2.1 The TSF shall ensure the operation of all the TOE’s capabilities when the following failures occur: exposure to operating conditions which are not detected according to the requirement Failure with preservation of secure state (FPT_FLS.1).

FPT_FLS.1 Failure with preservation of secure state Dependencies:

Refinement: The term “failure” above means “circumstances”. The TOE prevents failures for the “circumstances” defined above.

FRU_FLT.2 thus states the condition for normal secure operation of the TOE functions

(including coprocessors) within its expected operating conditions.

FPT_FLS.1

Hierarchical to:

FPT_FLS.1.1

Dependencies:

Refinement 1:

Failur e with preservation of secure state

No other components

The TSF shall preserve a secure state when the following types of failures occur: exposure to operating conditions which may not be tolerated according to the requirement Limited fault tolerance

(FRU_FLT.2) and where therefore a malfunction could occur.

ADV_SPM.1 Informal TOE security policy model

The term “failure” above also covers “circumstances”. Then the

TOE prevents failures for the “circumstances” defined above.

The refinement above is defined in [BSI-PP-0002]. An additional refinement is made here to capture features specific to the TOE.

Refinement 2: The term “failure” above also covers the following:

(i) Attempts to access memory outside an area defined for the software being executed

(ii) Attempts to make an illegal access

(iii) Attempts to execute code from a type of memory not permitted by the software environment

5

(iv) Attempts to execute an illegal instruction code

(v) Processor halted by Smartcard Embedded Software

5

The “software environment” is a term used to capture the definition of acceptable memory use for the software system using the TOE. This would usually be at the level of operating system software.

Page 31 of 59 Revision 2.0, 23 February, 2007

HD65256D Security Target

– Public Version

Application notes:

HD65256D-CC-ST-0002

1. The TOE is required to implement an interrupt whenever a write to EEPROM takes place, to enable detection of failure conditions and preservation of a secure state by Smartcard

Embedded Software.

FPT_SEP.1

Hierarchical to:

FPT_SEP.1.1

FPT_SEP.1.2

Dependencies:

Refinement:

TSF domain separation

No other components

The TSF shall maintain a security domain for its own execution that protects it from interference and tampering by untrusted subjects.

The TSF shall enforce separation between the security domains of subjects in the TSC.

No dependencies.

The components which support the SFRs “Limited fault tolerance

(FRU_FLT.2)” and “Failure with preservation of secure state

(FPT_FLS.1)” shall be protected from interference of the Smartcard

Embedded Software.

5.1.1.2 Protection Against Abuse of Functionality

The TOE controls access to test mode. Following [BSI-PP-0002], this is specified using the extended functional family FMT_LIM, defined in section 8.5 of [BSI-PP-0002].

FMT_LIM.1 Limited capabilities

Hierarchical to:

FMT_LIM.1.1

No other components

The TSF shall be designed in a manner that limits their capabilities so that in conjunction with “Limited availability (FMT_LIM.2)” the following policy is enforced: Deploying Test Features after TOE

Delivery does not allow User Data to be disclosed or manipulated,

TSF data to be disclosed or manipulated, software to be reconstructed and substantial information about construction of TSF to be gathered which may enable other attacks.

Dependencies: FMT_LIM.2 Limited availability.

Application notes:

1. The “capabilities” referred to in FMT_LIM.1 are the functions implemented in the IC

Dedicated Test Software.

Revision 2.0, 23 February, 2007 Page 32 of 59

HD65256D Security Target

– Public Version

FMT_LIM.2 Limited availability

Hierarchical to: No other components

HD65256D-CC-ST-0002

FMT_LIM.2.1 The TSF shall be designed in a manner that limits their availability so that in conjunction with “Limited capabilities (FMT_LIM.1)” the following policy is enforced: Deploying Test Features after TOE

Delivery does not allow User Data to be disclosed or manipulated,

TSF data to be disclosed or manipulated, software to be reconstructed and substantial information about construction of TSF to be gathered which may enable other attacks.

FMT_LIM.1 Limited capabilities. Dependencies:

Application notes:

1. The “availability” referred to in FMT_LIM.2 are the functions implemented in the IC

Dedicated Test Software.

5.1.1.3 Storage of Production Data

The TOE stores identification/pre-personalisation data as described in section 2.4.2. This is included in [BSI-PP-0002] as the CC Part 2 extended functional component FAU_SAS.1, replacing FAU_GEN.1, and defined in section 8.6 of [BSI-PP-0002].

FAU_SAS.1

Hierarchical to:

Audit storage

No other components

FAU_SAS.1.1 The TSF shall provide test personnel before TOE Delivery with the capability to store the Initialisation Data and/or Pre-personalisation

Data and/or supplements of the Smartcard Embedded Software in the audit records.

No dependencies Dependencies:

Application notes:

1. The data covered by “Initialisation Data and/or Pre-personalisation Data and/or supplements of the Smartcard Embedded Software” is as identified in section 2.4.2.

The function Audit storage (FAU_SAS.1) is subject to the limitations as specified by Limited availability (FMT_LIM.2) above.

5.1.1.4 Protection against Physical Manipulation and Probing

FPT_PHP.3

Hierarchical to:

Resistance to physical attack

No other components

Revision 2.0, 23 February, 2007 Page 33 of 59

HD65256D Security Target

– Public Version

FPT_PHP.3.1

HD65256D-CC-ST-0002

The TSF shall resist physical manipulation and physical probing to the TSF by responding automatically such that the TSP is not violated.

Dependencies:

Refinement:

No dependencies

The TOE will implement appropriate measures to continuously counter physical manipulation and physical probing. Due to the nature of these attacks (especially manipulation) the TOE can by no means detect attacks on all of its elements. Therefore, permanent protection against these attacks is required ensuring that the TSP could not be violated at any time. Hence, “automatic response” means here (i) assuming that there might be an attack at any time and

(ii) countermeasures are provided at any time.

5.1.1.5

FDP_ITT.1.1

Protection against Leakage

FDP_ITT.1

Hierarchical to:

Basic internal transfer protection

No other components

The TSF shall enforce the Data Processing Policy to prevent the disclosure of user data when it is transmitted between physicallyseparated parts of the TOE.

Dependencies:

Refinement:

[FDP_ACC.1 Subset access control, or FDP_IFC.1 Subset information flow control]

The different memories, the CPU and other functional units of the

TOE (e.g. a cryptographic co-processor) are seen as physicallyseparated parts of the TOE.

The Data Processing Policy is defined under FDP_IFC.1 below.

FPT_ITT.1

Hierarchical to:

FPT_ITT.1.1

Dependencies:

Refinement:

Basic internal TSF data transfer protection

No other components

The TSF shall protect TSF data from disclosure when it is transmitted between separate parts of the TOE.

No dependencies.

The different memories, the CPU and other functional units of the

TOE (e.g. a cryptographic co-processor) are seen as separated parts of the TOE.

This requirement is equivalent to FDP_ITT.1 above but refers to

TSF data instead of User Data. Therefore, it should be understood as to refer to the same Data Processing Policy defined under

FDP_IFC.1 below.

Revision 2.0, 23 February, 2007 Page 34 of 59

HD65256D Security Target

– Public Version

FDP_IFC.1 Subset information flow control

Hierarchical to: No other components

HD65256D-CC-ST-0002

FDP_IFC.1.1 The TSF shall enforce the Data Processing Policy on all confidential data when they are processed or transferred by the TOE or by the

Smartcard Embedded Software.

FDP_IFF.1 Simple security attributes Dependencies:

Data Processing Policy User Data and TSF data shall not be accessible from the TOE except when the Smartcard Embedded Software decides to communicate the User Data via such an external interface. The protection shall be applied to confidential data only, but without the distinction of attributes controlled by the Smartcard Embedded Software.

5.1.1.6 Cryptographic Support

The TOE generates random numbers that can be used for cryptographic key generation. To capture the functional requirement, the family FCS_RND, defined in section 8.4 of [BSI-PP-

0002] is used.

Quality metric for random numbers FCS_RND.1

FCS_RND.1.1 The TSF shall provide a mechanism to generate random numbers that meet the requirements of the monobit, poker, runs, long run, and autocorrelation tests in [AIS31].

5.1.2 TOE Security Functional Requir ements Based on [PA]

5.1.2.1 Cryptographic Support

The TOE provides a DES coprocessor. The DES coprocessor can be used to implement single or triple DES.

FCS_COP.1 Cryptographic operation

FCS_COP.1 is iterated here to address both the DES encryption and decryption (FCS_COP.1

[DES]).

DES Encryption and Decryption

FCS_COP.1 [DES]

Hierarchical to: No other components

FCS_COP.1.1 [DES] The TSF shall perform encryption and decryption in accordance with a specified cryptographic algorithm Data Encryption Standard

(DES) and cryptographic key sizes of 56 bit that meet the following standards:

Revision 2.0, 23 February, 2007 Page 35 of 59

HD65256D Security Target

– Public Version

HD65256D-CC-ST-0002

U.S. Department of Commerce / National Bureau of Standards

Data Encryption Standard (DES), FIPS PUB 46-3, 1999 October 25

Dependencies: [FDP_ITC.1 Import of user data without security attributes or

FCS_CKM.1 Cryptographic key generation]

FCS_CKM.4 Cryptographic key destruction

FMT_MSA.2 Secure security attributes

Application notes:

1. Although the TOE provides a DES coprocessor, DES is only ever used as an encryption function in the context of particular Smartcard Embedded Software, and for this reason it is noted that application software may need to use triple DES to achieve a suitable strength. In this case, Smartcard Embedded Software shall use the TOE to implement triple DES, as described in the guidance for software developers in section 16.3.1 of [HM].

5.1.3 Other TOE Security Functional Requirements

FDP_ACC.1 Subset access control

FDP_ACC.1 is iterated here to address both the control over software to write to certain controlled registers (FDP_ACC.1 [CRP]) and software to write to protected pages of EEPROM memory (FDP_ACC.1 [WPP]).

FDP_ACC.1 [CRP]

Hierarchical to: No other components

FDP_ACC.1.1 [CRP] The TSF shall enforce the Controlled-Register Policy on software to set bits in defined, security-relevant registers.

Here, policy : Controlled-Register Policy

Subjects : software

Objects : bits in defined, security-relevant registers

Operations : to set

Controlled-Register Policy

The ability to set the values in the controlled registers is restricted to software instructions executed in ROM.

FDP_ACF.1 Security attribute based access control Dependencies:

Application Notes:

1. The controlled registers are those defined in FDP_ACC.1.1 [CRP].

FDP_ACC.1 [WPP]

Hierarchical to: No other components

Revision 2.0, 23 February, 2007 Page 36 of 59

HD65256D Security Target

– Public Version

FDP_ACC.1.1 [WPP]

HD65256D-CC-ST-0002

The TSF shall enforce the Write-Protect Policy on software to write to EEPROM.

Here, policy : Write-Protect Policy

Subjects : software

Objects : EEPROM

Operations : to write

Write-Protect Policy An attempt to write to EEPROM shall fail, leaving the previous memory contents unaltered if the relevant EEPROM page is write protected.

Dependencies:

Once a page is write-protected, this protection cannot be removed.

FDP_ACF.1 Security attribute based access control

Application Notes:

1. The setting of write protection is described in [HM].

2. All modes of EEPROM write (see [HM]) are covered by this policy.

FDP_ACF.1 Security attribute based access control

FDP_ACF.1 is iterated here to address both the security attribute based access control over software to write to certain controlled registers (FDP_ACF.1 [CRP]) and software to write to protected pages of EEPROM memory (FDP_ACF.1 [WPP]).

FDP_ACF.1 [CRP]

Hierarchical to:

FDP_ACF.1.1 [CRP]

6

No other components

FDP_ACF.1.2 [CRP]

The TSF shall enforce the Controlled-Register Policy to objects based on the following:

Subject: software running on the ROM

Object: control registers relating to the FMU attributes: to have read and/or write access normally

The TSF shall enforce the following rules to determine if an operation among controlled subjects and controlled objects is allowed: evaluate the corresponding permission control information:

“ The ability to set the values in the controlled registers is restricted to software operations executed from the ROM.” before, during or

6

FDP_ACF.1.1 is changed as follows according to Final Interpretation 103

FDP_ACF.1.1 The TSF shall enforce the [assignment: access control SFP] to objects based on the following: [assignment: list of subjects and objects controlled under the indicated SFP, and. for each, the SFP-relevant security attributes, or named groups of

SFP-relevant security attributes].

Page 37 of 59 Revision 2.0, 23 February, 2007

HD65256D Security Target

– Public Version

HD65256D-CC-ST-0002 after the access so that accesses to be denied can not be utilised by the subject attempting to perform the operation.

FDP_ACF.1.3 [CRP] The TSF shall explicitly authorise access of subjects to objects based on the following additional rules: none.

FDP_ACF.1.4 [CRP]

Dependencies:

The TSF shall explicitly deny access of subjects to objects based on the following additional rules: none.

FDP_ACC.1 Subset access control

FMT_MSA.3 Static attribute initialisation

FDP_ACF.1 [WPP]

Hierarchical to: No other components

FDP_ACF.1.1 [WPP]

5

The TSF shall enforce the Write Protect Policy to objects based on the memory area where the access is performed and the operation to be performed.

FDP_ACF.1.2 [WPP] The TSF shall enforce the following rules to determine if an operation among controlled subjects and controlled objects is allowed: evaluate the corresponding permission control information:

“ An attempt to write to EEPROM shall fail, leaving the previous memory contents unaltered if write protection is set for the relevant

EEPROM page. Once a page is write-protected, this protection cannot be removed.” before, during or after the access so that accesses to be denied can not be utilised by the subject attempting to perform the operation.

FDP_ACF.1.3 [WPP]

FDP_ACF.1.4 [WPP]

Dependencies:

The TSF shall explicitly authorise access of subjects to objects based on the following additional rules: none.

The TSF shall explicitly deny access of subjects to objects based on the following additional rules: none.

FDP_ACC.1 Subset access control

FMT_MSA.3 Static attribute initialisation

5.1.4 TOE Security Assurance Requirements

The assurance level for this Security Target is EAL4 augmented, as in section 5.1.2 of [BSI-PP-

0002].

The augmentations to EAL4 are:

ADV_IMP.2 - this adds the full implementation representation of the security functions to the evaluation scope

Revision 2.0, 23 February, 2007 Page 38 of 59

HD65256D Security Target

– Public Version

HD65256D-CC-ST-0002

ALC_DVS.2 - this increases the confidence in the vital area of developer security measures to the highest CC level

AVA_MSU.3 - this adds evaluator testing of the potential for misconfiguration of the TOE within the evaluation scope

AVA_VLA.4 - this increases the scope of vulnerability analysis and penetration testing to the highest CC level.

The minimum strength of function is SOF-high. In addition, the quality of the mechanisms contributing to the information leakage resistance of the DES coprocessor can be analysed using probabilistic methods based on measurement of the power consumption of the TOE - SOF-high is also claimed for this mechanism. Also note that the strength of the cryptographic algorithms is out of the scope of the TOE.

Refinements of the assurance requirements required by [BSI-PP-0002], and implemented by

Renesas for the TOE, are described in section 5.1.3 of [BSI-PP-0002].

5.2 Secur ity Requir ements for the Envir onment

5.2.1 Security Requirements for the IT Environment from [PA]

In section 5.2.1 of [BSI-PP-0002], only non-IT security requirements are placed on the environment (see section 5.2.2). Although these requirements are applicable to Smartcard

Embedded Software, it is not necessary or appropriate to place specific functional requirements.

However, the following requirements for the environment are adopted from [PA].

The security functional requirement “Cryptographic operation (FCS_COP.1)” met by the TOE has the following dependencies

- [FDP_ITC.1 Import of user data without security attributes or FCS_CKM.1 Cryptographic key generation],

- FCS_CKM.4 Cryptographic key destruction,

- FMT_MSA.2 Secure security attributes.

These requirements all address the appropriate management of cryptographic keys used by the specified cryptographic function. All requirements concerning key management shall be fulfilled by the environment since the Smartcard Embedded Software is designed for a specific application context and uses the cryptographic functions provided by the TOE. Note that, however, for FCS_COP.1, the dependencies are unfulfilled because the environment is unknown

(it is an issue for the user of the chip of course).

The environment shall meet the requirement “Import of user data without security attributes

(FDP_ITC.1)” or “Cryptographic key generation (FCS_CKM.1)” as specified below. Note that, however, for FDP_ITC.1, the operations are deliberately uncompleted and dependencies unfulfilled because the environment is unknown (it is an issue for the user of the chip of course).

FDP_ITC.1 Import of user data without security attributes

Revision 2.0, 23 February, 2007 Page 39 of 59

HD65256D Security Target

– Public Version

Hierarchical to: No other components.

FDP_ITC.1.1

FDP_ITC.1.2

HD65256D-CC-ST-0002

The TSF shall enforce the [assignment: access control SFP and/or information flow control SFP] when importing user data, controlled under the SFP, from outside of the TSC.

The TSF shall ignore any security attributes associated with the user data when imported from outside the TSC.

FDP_ITC.1.3

Dependencies:

The TSF shall enforce the following rules when importing user data controlled under the SFP from outside the TSC: [assignment: additional importation control rules].

[FDP_ACC.1 Subset access control, or

FDP_IFC.1 Subset information flow control]

FMT_MSA.3 Static attribute initialisation

FCS_CKM.1

Hierarchical to:

FCS_CKM.1.1

Cryptographic key generation

No other components.

The TSF shall generate cryptographic keys in accordance with a specified cryptographic key generation algorithm [assignment: cryptographic key generation algorithm] and specified cryptographic key sizes [assignment: cryptographic key sizes], that meet the following: [assignment: list of standards].

Dependencies: [FCS_CKM.2 Cryptographic key distribution or FCS_COP.1

Cryptographic operation]

FCS_CKM.4 Cryptographic key destruction

FMT_MSA.2 Secure security attributes

The environment shall meet the requirement “Cryptographic key destruction (FCS_CKM.4)” as specified below. Note that, however, for FCS_CKM.4, the operations are deliberately uncompleted and dependencies unfulfilled because the environment is unknown (it is an issue for the user of the chip of course).

FCS_CKM.4

Hierarchical to:

FCS_CKM.4.1

Dependencies:

Cryptographic key destruction

No other components.

The TSF shall destroy cryptographic keys in accordance with a specified cryptographic key destruction method [assignment: cryptographic key destruction method] that meets the following: [assignment: list of standards].

[FDP_ITC.1 Import of user data without security attributes or

FCS_CKM.1 Cryptographic key generation]

Revision 2.0, 23 February, 2007 Page 40 of 59

HD65256D Security Target

– Public Version

FMT_MSA.2 Secure security attributes

HD65256D-CC-ST-0002

The environment shall meet the requirement “Secure security attributes (FMT_MSA.2)” as specified below. Note that, however, for FMT_MSA.2, the operations are deliberately uncompleted and dependencies unfulfilled because the environment is unknown (it is an issue for the user of the chip of course).

FMT_MSA.2

Hierarchical to:

FMT_MSA.2.1

Dependencies:

Secure security attributes

No other components.

The TSF shall ensure that only secure values are accepted for security attributes.

ADV_SPM.1 Informal TOE security policy model

[FDP_ACC.1 Subset access control or FDP_IFC.1 Subset information flow control]

FMT_MSA.1 Management of security attributes

FMT_SMR.1 Security roles

5.2.2 Security Requirements for the Non-IT Environment

5.2.2.1 Security Requirements for the Non-IT Environment from [BSI-PP-0002]

As in section 5.2.2 of [BSI-PP-0002], this ST applies the following requirements:

RE.Phase-1 Design and Implementation of the Smartcard Embedded Software

The developers shall design and implement the Smartcard Embedded

Software in such way that it meets the requirements from the following documents:

(i) The TOE hardware manual [HM], user guidance manual [UGM1], and the hardware application notes.

(ii) Major findings of the hardware evaluation reports relevant for the

Smartcard Embedded Software.

The developers shall implement the Smartcard Embedded Software in a way that it protects security relevant User Data (especially cryptographic keys) as required by the security needs of the specific application context.

In particular, the Smartcard Embedded Software shall not disclose secret

User Data to unauthorised users or processes as defined for the application context. Similarly the Smartcard Embedded Software shall not allow unauthorised users or processes to use or modify security relevant User

Data.

Revision 2.0, 23 February, 2007 Page 41 of 59

HD65256D Security Target

– Public Version

HD65256D-CC-ST-0002

RE.Process-Card Protection during Packaging, Finishing and Per sonalisation

The Handset Manufacturer (after TOE Delivery up to the end of Phase 6) shall use adequate security measures to maintain confidentiality and integrity of the TOE and of its manufacturing and test data (to prevent any possible copy, modification, retention, theft or unauthorised use).

Section 8.2.2 of [BSI-PP-0002] gives examples of ways in which Smartcard Embedded Software may implement security issues. The TOE does not itself require any of these functions to be implemented in software – this is entirely a decision to be based on the software context.

However, the TOE aims to provide support for software implementation of FDP_SDI.1 and

FPT_AMT.1 (the examples given in [BSI-PP-0002]) through features such as the EWE interrupt

– cf. FPT_FLS.1 in section 5.1.1.1 and SF.ESFunctions in section 6.1.

5.2.2.2 Security Requirements for the Non-IT Environment from [PA]

For implementation of cryptographic functions in Smartcard Embedded Software, the following requirement from [PA] is included:

RE.Cipher Cipher Schemes

The developers of Smartcard Embedded Software must not implement routines in a way which may compromise keys when the routines are executed as part of the Smartcard Embedded Software. Performing functions which access cryptographic keys could allow an attacker to misuse these functions to gather information about the key which is used in the computation of the function.

Keys must be kept confidential as soon as they are generated. The keys must be unique with a very high probability, as well as cryptographically strong. For example, it must be ensured that it is not possible to derive the private key from a public key if asymmetric algorithms are used. If keys are imported into the TOE and/or derived from other keys quality and confidentiality must be maintained. This implies that an appropriate key management has to be realised in the environment.

Revision 2.0, 23 February, 2007 Page 42 of 59

HD65256D Security Target

– Public Version

HD65256D-CC-ST-0002

6. TOE Summar y Specification

6.1 TOE Secur ity Functions

1. SF.HWProtect

The TOE is protected from attacks on the operation of the IC hardware. The protection features include detection of out-of-range supply voltages, frequencies or temperatures, detection of illegal address or instruction, and physical security.

Detection of an error causes the HD65256D to enter a reset state.

Correct operating ranges are defined in [HM].

The memory address and data encryption of SF.HWProtect use probabilistic or permutational effects and are included in the AVA_SOF analysis. Except for them,

SF.HWProtect does not use probabilistic or permutational effects.

2. SF.LeakProtect

The TOE Hardware protects against leakage of information from the IC. The protection features include:

Functions designed to alter the power consumption of the device

DES protection – the DES coprocessor contains additional measures to resist sidechannel attacks.

SF.LeakProtect uses probabilistic or permutational effects and has to be included in the

AVA_SOF analysis with SOF-high.

3. SF.RNG

The TOE includes a physical random number generator (HW RNG) designed to produce random numbers for the generation of cryptographic keys and for other critical uses. This random number generator meets the requirements of application class P2 (as specified in

[AIS31]).

The TOE can be used to generate 64-bit random numbers which satisfy the requirements of the monobit, poker, runs, long run, and autocorrelation tests in [AIS31]. Note that the RNG generates a 64-bit (16-bit × 4) random number at one time, but it is provided to the user of the TOE by 16 bits.

Application Notes

1. The TOE provides a tamper resistant hardware random number generator (see section 10 of [HM]). However, in order to provide additional assurance to the User software that the hardware is functioning, [AIS31] requires the use of an on-line test of the RNG. A suitable test routine is given in section 6 of

[UGM1]

.

Revision 2.0, 23 February, 2007 Page 43 of 59

HD65256D Security Target

– Public Version

HD65256D-CC-ST-0002

SF.RNG uses probabilistic or permutational effects and has to be included in the AVA_SOF analysis with SOF-high.

4. SF.DES

The TOE provides a hardware DES coprocessor that carries out DES encryption and decryption in ECB mode according to the following standard: a) U.S. Department of Commerce / National Bureau of Standards Data Encryption

Standard, FIPS PUB 46-3, 1999 October 25.

Application Notes

1. The DES coprocessor implements single DES encrypt and decrypt operations, and has been optimised to allow easy implementation of triple-DES (as described in the standard) in Smartcard Embedded Software, as described in section 16.3.1 of [HM].

2. Although the TOE provides a DES coprocessor, DES is only actually used as an encryption function in the context of particular Smartcard Embedded Software. For some application contexts, triple DES (as described in section 16.3.1 of [HM]) may be required in order to achieve a suitable strength of function if the Smartcard Embedded

Software is to be evaluated

7

– this is a matter for the Smartcard Embedded Software security target.

3. The TOE implements ECB mode - software can implement other modes such as CBC.

4. To provide secure embedded software, the software developer is required to ensure that the DES is used in a way that does not compromise the key or plain text (see A.Plat-

Appl, A.Resp-Appl and A.Key-Function). Guidance for the implementation of secure

Smartcard Embedded Software is given in [UGM1].

SF.DES uses probabilistic or permutational effects but does not need to be included in the

AVA_SOF analysis with SOF-high since the function is beyond the scope of a Common

Criteria evaluation.

5. SF.FMU

The TOE firewall management unit enables software to control addresses that can be accessed in the following two ways: a) The FMU checks that a target address used in any instruction is within/out of specified limits.

If a target address is not within accessible areas then the TOE enters the reset state or

FMU interrupt.

7

Although strength of cryptographic functions is beyond the scope of a Common Criteria evaluation, triple DES would probably be required to achieve SOF-high for Smartcard Embedded Software.

Page 44 of 59 Revision 2.0, 23 February, 2007

HD65256D Security Target

– Public Version

HD65256D-CC-ST-0002 b) In addition, the FMU may enforce a policy that the TOE may not execute code in either EEPROM or RAM, or both.

Changes to these policies can only be made by software executing in ROM.

Application Notes:

1. The accessible address registers are defined in section 12.2 of [HM].

SF.FMU does not use probabilistic or permutational effects.

6. SF.ESFunctions

The scope of the TOE evaluation includes correct operation of aspects such as the CPU instructions, memory functions and standard peripherals such as memories, registers, I/O interfaces, and timers as specified in [HM]. In addition, the TOE offers hardware and software facilities that are designed to enable Smartcard Embedded Software to address threats to its correct operation by taking control of the operating environment. The

Smartcard Embedded Software developer can rely on the following TOE functionality that has been specifically evaluated as part of the TOE:

EWE Interrupt

Every time the TOE writes to EEPROM, it generates a non-maskable interrupt (the

EWE interrupt). When this interrupt occurs, execution is passed to a user-definable address held in the EWE vector. A user can therefore add code at this location to carry out a variety of checks, for example to confirm the integrity of data, or the context in which certain areas of EEPROM are being written.

If a new EWE interrupt is received before the previous one has been cleared then the

TOE enters the reset state.

CPU Halt

When the halt bit is set by user software, the TOE will stop execution until an external reset is received.

SF.ESFunction does not use probabilistic or permutational effects.

7. SF.TestModeControl

Once the TOE has been set to user mode, test mode functions are made not available.

The user mode is irreversibly set. It is however not impossible to transit back to test mode though that requires specific knowledge and highly sophisticated techniques.

8

8

The potential vulnerability with respect to the possibility of the transition back to user mode is included in the vulnerability analysis.

Page 45 of 59 Revision 2.0, 23 February, 2007

HD65256D Security Target

– Public Version

HD65256D-CC-ST-0002

SF.TestModeControl uses probabilistic or permutational effects and has to be included in the

AVA_SOF analysis with SOF-high.

8. SF.EEPAccess

The TOE allows any page of EEPROM to have writes (or erase) disallowed by setting the page to have a protected state. If a write (or erase) is attempted to a protected page then it will leave the page content unaltered.

Protection of a page against writes is permanent once set.

SF.EEPAccess does not use probabilistic or permutational effects.

9. SF.Inject

During manufacture, each TOE is injected with data that uniquely identifies the individual

IC. If specified for the Smartcard Embedded Software included, then additional data (some of it IC-specific) may also be injected during manufacture.

SF.Inject does not use probabilistic or permutational effects.

The Reset State

The reset state is referred to in several of the Security Functions above. In the reset state, the chip stops execution until a reset signal is received on the reset line. When a reset occurs, the following actions are carried out:

The CPU resets to its initial state

Registers are set to their initial values (as defined in [HM])

Execution begins at the location in the reset vector (as defined in [HM]).

Revision 2.0, 23 February, 2007 Page 46 of 59

HD65256D Security Target

– Public Version

6.2

HD65256D-CC-ST-0002

Cor r espondence Between TOE Secur ity Function and SFR

Table below shows the correspondence between SFRs and each of the Security Functions provided in the section 6.1 above.

Table 6-1: TOE Security Functions Mapping to SFRs

TOE Security Function

SF.HWProtect,

SFR

FRU_FLT.2, FPT_FLS.1, FPT_SEP.1, FPT_PHP.3

SF.LeakProtect

SF.RNG

FDP_ITT.1, FPT_ITT.1, FDP_IFC.1

FCS_RND.1

SF.DES

SF.FMU

FCS_COP.1 [DES]

FRU_FLT.2, FPT_FLS.1, FPT_SEP.1, FPT_PHP.3, FDP_ACC.1

[CRP], FDP_ACF.1 [CRP]

SF.ESFunctions, FRU_FLT.2, FPT_FLS.1, FPT_SEP.1, FPT_PHP.3

SF.TestModeControl FMT_LIM.1, FMT_LIM.2

SF.EEPAccess

SF.Inject

FPT_FLS.1, FPT_SEP.1, FDP_ACC.1 [WPP], FDP_ACF.1 [WPP]

FAU_SAS.1

6.3 Assur ance Measur es

The TOE meets the requirements for EAL4 (as defined in [CC/3]) and the following augmentations:

ADV_IMP.2

ALC_DVS.2

AVA_MSU.3

AVA_VLA.4

It also meets the requirements of the refinements made to the assurance requirements in section

5.1.3 of [BSI-PP-0002].

The table below maps assurance requirements to the documents describing the relevant requirements:

Page 47 of 59 Revision 2.0, 23 February, 2007

HD65256D Security Target

– Public Version

HD65256D-CC-ST-0002

Table 6-2: Documents Meeting Assurance Requirements

Document

Security Policy Model

Hardware Manual

[CC/3] Evidence Item

Security Policy Model

Security Function

Functional Specification

User Guidance and administrator guidance documentation

Related Assurance

Components

ADV_SPM

ADV_FSP

ADV_FSP

AGD_USR,

AGD_ADM

User Guidance Manual

High-Level and Low-Level

Design Documentation Set

Source Code*

Correspondence Mapping

Test Documentation Set

User Guidance and administrator guidance documentation

AGD_USR,

AGD_ADM

ADO_IGS

Correspondence analysis between TOE

Summary Specification and functional specification, high level design, low level design and implementation

ADV_RCR

High-level design, low-level design

ADV_HLD,

ADV_LLD

ADV_IMP Implementation

Testing, test depth and test coverage documentation

ATE

Site Information

Development tools documentation ALC

Configuration management documentation ACM

Delivery procedures

Misuse Analysis

ADO_DEL

AVA_MSU Misuse Analysis

Strength of Function

Analysis

Strength of Function Analysis

Vulnerability Analysis Vulnerability Analysis

Note: The source code exists in an electronic data form.

AVA_SOF

AVA_VLA

Revision 2.0, 23 February, 2007 Page 48 of 59

HD65256D Security Target

– Public Version

HD65256D-CC-ST-0002

7. PP Claims

7.1 PP Refer ence

This ST conforms to [BSI-PP-0002]. As a notable point, however, this ST includes the initial personalisation process in phase 5 as a part of the TOE lifecycle.

Note that [PA] is used to define additional requirements relating to cryptographic functions.

This ST is also [PA] conformant.

7.2 PP Tailor ing

FCS_RND.1 is completed with a quality metric – see section 5.1.1.6.

7.3 PP Additions

The inclusions from [BSI-PP-0002] are clearly shown in the relevant section titles. All other assumptions, threats, objectives and SFRs, in sections 3.2.2, 3.2.3, 3.3.2, 3.4.2, 4.1.2, 4.1.3, 4.2.2,

5.1.2, 5.1.3, 5.2.1, and 5.2.2.2 are additional to those in the PP.

Revision 2.0, 23 February, 2007 Page 49 of 59

HD65256D Security Target

– Public Version

HD65256D-CC-ST-0002

8. Rationale

8.1 Secur ity Objectives Rationale

The way in which [BSI-PP-0002] assumptions, organisational security policy and threats are met by objectives is given in section 7.1 of [BSI-PP-0002]. The table below includes the mapping from section 7.1 of [BSI-PP-0002] and adds the rationale for the additional assumptions, policy and threats in this Security Target.

Table 8-1: Coverage of Security Assumptions, Policies and Threats by Objectives

Assumption/Threat/

Organisational Security Policy

A.Key-Function

A.Plat-Appl

A.Process-Card

A.Resp-Appl

A.InjDatSupp

P.Add-Functions

P.Process-TOE

T.Leak-Inherent

T.Phys-Probing

T.Phys-Manipulation

T.Malfunction

T.Leak-Forced

T.Abuse-Func

T.NoSWDetect

T.NoSWResponse

T.RND

Addressed by Objective

OE.Plat-Appl, OE.Resp-Appl

OE.Plat-Appl

OE.Process-Card

OE.Resp-Appl

OE.InjDatSupp

O.Add-Functions

OE.Process-TOE, O.Identification

O.Leak-Inherent

O.Phys-Probing

O.Phys-Manipulation

O.Malfunction

O.Leak-Forced

O.Abuse-Func

O.SWDetect

O.SWResponse

O.RND

A.Key-Function is enforced by OE.Plat-Appl and OE.Resp-Appl, which directly requires the embedded software to use the features in TOE documentation to take measures to ensure that keys are not compromised by the way in which the TOE’s cryptographic functions are used.

Note that this recognises the fact that measures in hardware are only part of the solution for software TOEs, which must also ensure that their algorithms protect keys.

A.Plat-Appl is enforced by a directly corresponding requirement on the environment in OE.Plat-

Appl. (Note that as in section 7.1 of [BSI-PP-0002] this applies to Phase 1 of the lifecycle.)

A.Process-Card is enforced by a directly corresponding requirement on the environment in

OE.Process-Card. (Note that as in section 7.1 of [BSI-PP-0002] this applies to Phases 4-6 of the lifecycle.)

A.Resp-Appl is enforced by a directly corresponding requirement on the environment in

OE.Resp-Appl. (Note that as in section 7.1 of [BSI-PP-0002] this applies to Phase 1 of the lifecycle.)

Revision 2.0, 23 February, 2007 Page 50 of 59

HD65256D Security Target

– Public Version

HD65256D-CC-ST-0002

A.InjDatSupp is enforced by a directly corresponding requirement on the environment in

OE.InjDatSupp.

OE.Process-TOE requires the TOE Manufacturer to implement those measures assumed in

P.Process-TOE. Therefore, the organisational security policy is covered by this objective, as far as organisational measures are concerned. The only issue not completely covered by these measures is the fact that the TOE has to support the possibility of unique identification. This is the content of O.Identification. Therefore, the organisational security policy is covered by

OE.Process-Card and O.Identification. (Note that as in section 7.1 of [BSI-PP-0002] this applies to Phases 2-3 of the lifecycle.)

The basic rationale for T.Leak-Inherent, T.Phys-Probing, T.Phys-Manipulation, T.Malfunction,

T.Leak-Forced, and T.Abuse-Func is given in section 7.1 of [BSI-PP-0002]: for all threats the corresponding objectives O.Leak-Inherent, O.Phys-Probing, O.Phys-Manipulation,

O.Malfunction, O.Leak-Forced, and O.Abuse-Func are stated in a way, which directly corresponds to the description of the threat. It is clear from the description of each objective, that the corresponding threat is removed if the objective is valid. More specifically, in every case the ability to use the attack method successfully is countered, if the objective holds.

Since O.Add-Functions requires the TOE to implement exactly the same specific security functionality as required by P.Add-Functions, the organisational security policy is covered by the objective. The text below gives further rationale from [PA].

Compared to [BSI-PP-0002] a clarification has been made for the security objective “Usage of

Hardware Platform (OE.Plat-Appl)”: If required the Smartcard Embedded Software shall use these cryptographic services of the TOE and their interface as specified. In addition, the

Smartcard Embedded Software must implement functions which perform operations on keys (if any) in such a manner that they do not disclose information about confidential data. This addition ensures that the assumption A.Plat-Appl is still covered by the objective OE.Plat-Appl although additional functions are being supported according to O.Add-Functions.

Compared to [BSI-PP-0002] a clarification has been made for the security objective “Treatment of User Data (OE.Resp-Appl)”: By definition, encryption data, plain text data, and cryptographic keys are User Data. So, the Smartcard Embedded Software will protect such data if required, and the keys and functions are used appropriately in order to ensure the strength of cryptographic operation. Quality and confidentiality must be maintained for keys that are imported and/or derived from other keys. This implies that appropriate key management has to be realised in the environment. These measures make sure that the assumption A.Resp-Appl is still covered by the security objective OE.Resp-Appl although additional functions are being supported according to

P.Add-Functions.

The justification of the additional policy and the additional assumption show that they do not contradict to the rationale already given in [BSI-PP-0002] for the assumptions, policy and threats defined there.

Smartcard Embedded Software may implement measures using the ability given by the TOE to embedded software to detect and respond to the results of attacks based on these threats, in

O.SWDetect and O.SWResponse. This can help address some of the core threats – T.Phys-

Manipulation, T.Malfunction and T.Abuse-Func by detecting the results of attempts to tamper

Revision 2.0, 23 February, 2007 Page 51 of 59

HD65256D Security Target

– Public Version

HD65256D-CC-ST-0002 with the operation of the IC, and using additional defensive measures at the level of the target of the attack

9

. However, since no assumptions are made about the content of Smartcard Embedded

Software (and hence the use made of these features), these objectives are not included for the core threats in the table above.

T.NoSWDetect and T.NoSWResponse are directly addressed by O.SWDetect and

O.SWResponse respectively.

T.RND is addressed by O.RND.

8.2 Secur ity Requir ements Rationale

The way in which [BSI-PP-0002] objectives are implemented by SFRs and requirements on the environment is given in section 7.2 of [BSI-PP-0002]. The table below includes the mapping from section 7.2 of [BSI-PP-0002] and adds the rationale for the additional SFRs in this Security

Target.

Objective

O.Leak-Inherent

O.Phys-Probing

O.Phys-Manipulation

O.Malfunction

O.Leak-Forced

O.Abuse-Func

Table 8-2: Coverage of Objectives by SFRs

Addressed by SFR

Security Requirements for the

Environment

FDP_ITT.1,

FPT_ITT.1,

FDP_IFC.1

FPT_PHP.3

FPT_PHP.3

FRU_FLT.2,

FPT_FLS.1,

FPT_SEP.1

FDP_ITT.1,

FPT_ITT.1,

FDP_IFC.1,

FRU_FLT.2,

FPT_FLS.1,

FPT_SEP.1,

FPT_PHP.3

FMT_LIM.1,

FMT_LIM.2,

FDP_ITT.1,

FPT_ITT.1,

FDP_IFC.1,

FPT_PHP.3,

FRU_FLT.2,

FPT_FLS.1,

FPT_SEP.1

RE.Phase-1

RE.Phase-1

RE.Phase-1

RE.Phase-1

9

An attacker only stands to gain in a material sense if the applications themselves are attacked, since these represent the only assets that yield direct benefits to the attacker.

Page 52 of 59 Revision 2.0, 23 February, 2007

HD65256D Security Target

– Public Version

HD65256D-CC-ST-0002

Objective Addressed by SFR

Security Requirements for the

Environment

O.Identification

O.RND

FAU_SAS.1

FCS_RND.1,

FDP_ITT.1,

FPT_ITT.1,

FDP_IFC.1,

FPT_PHP.3,

FRU_FLT.2,

FPT_FLS.1,

FPT_SEP.1

RE.Phase-1

O.Add-Functions FCS_COP.1 [DES]

RE.Phase-1

RE.Cipher

O.SWDetect

FPT_FLS.1,

FDP_ACC.1 [CRP],

FDP_ACC.1 [WPP],

FDP_ACF.1 [CRP],

FDP_ACF.1 [WPP]

FPT_FLS.1 O.SWResponse

OE.Plat-Appl

OE.Process-TOE

OE.Process-Card

RE.Phase-1

Assurance Components: refer to below

RE.Process-Card, possibly supported by RE.Phase-1

OE.Resp-Appl

FDP_ITC.1,

FCS_CKM.1,

FCS_CKM.4,

FMT_MSA.2

RE.Phase-1

OE.InjDatSupp RE.Phase-1

♣ Assurance Components: Delivery (ADO_DEL); Installation, generation, and startup (ADO_IGS) (using Administrator

Guidance (AGD_ADM), User guidance (AGD_USR)); CM automation (ACM_AUT); CM Capabilities (ACM_CAP); CM

Scope ACM_SCP); Development Security (ALC_DVS); Life Cycle Definition (ALC_LCD); Tools and Techniques

(ALC_TAT)

Reference is made to section 7.2 of [BSI-PP-0002] for the basic rationale. The remainder of this section deals with the additional parts of the rationale introduced for this Security Target.

It is noted that the features covered by FDP_ACC.1 and FDP_ACF.1 address potential physical manipulation and malfunction attacks because they constrain the ways in which execution can occur. Furthermore, these access control measures directly protect parameters controlling some of the other security measures provided under FPT_FLS.1 from external attacks (e.g. only

Smartcard Embedded Software in ROM can set firewall management unit parameters, hence attacks based on changing these parameters in other conditions induced by attackers will be prevented).

O.Phys-Manipulation and O.Malfunction can be further addressed by Smartcard Embedded

Software by using the TOE’s features that allow embedded software to detect and respond to execution states that could represent attacks (included under FPT_FLS.1). However, this depends on the Smartcard Embedded Software and is therefore beyond the scope of the TOE.

Revision 2.0, 23 February, 2007 Page 53 of 59

HD65256D Security Target

– Public Version

HD65256D-CC-ST-0002

The DES requirement of O.Add-Functions is directly implemented by FCS_COP.1.1.

Additional security requirements on the environment, relating to the use of this functionality, are included in RE.Phase-1 and RE.Cipher. Rationale for this is excerpted from [PA] as follows.

The security functional requirement “Cryptographic operation (FCS_COP.1)” exactly requires those functions to be implemented which are demanded by O.Add-Functions. Therefore,

FCS_COP.1 is suitable to meet the security objective.

Nevertheless, the developer of the Smartcard Embedded Software must ensure that the additional functions are used as specified and that the User Data processed by these functions are protected as defined for the application context. These issues are addressed by the requirement

RE.Phase-1 and more specifically by the security functional requirements specified below.

[FDP_ITC.1 Import of user data without security attributes or FCS_CKM.1 Cryptographic key generation],

FCS_CKM.4 Cryptographic key destruction,

FMT_MSA.2 Secure security attributes. which will be fulfilled in the environment (addressed by the security environment objective

OE.Resp-Appl), and the details are not known.

The security functional requirements required to meet the security objectives O.Leak-Inherent,

O.Phys-Probing, O.Malfunction, O.Phys-Manipulation and O.Leak-Forced define how to implement the specific security functionality. However, key-dependent functions could be implemented in the Smartcard Embedded Software. In this case RE.Cipher requires that these functions ensure that confidential data (User Data) cannot be disclosed while they are just being processed by the Smartcard Embedded Software. Therefore, with respect to the Smartcard

Embedded Software the issues addressed by the objectives just mentioned are addressed by the requirement RE.Cipher.

The use of cryptographic algorithms requires use of appropriate keys - otherwise they do not provide security. The requirement RE.Cipher addresses these specific issues since cryptographic keys and other data are provided by the Smartcard Embedded Software. RE.Cipher requires that keys must be kept confidential. They must be unique with a very high probability, cryptographically strong etc. If keys are imported into the TOE (usually after TOE Delivery), it must be ensured that quality and confidentiality is maintained. Therefore, with respect to the environment the issues addressed (i) by the objectives just mentioned and (ii) implicitly by

O.Add-Functions, are addressed by the requirement RE.Cipher.

The justification of the security objective O.Add-Functions and the additional requirements (both for the TOE and its environment) show that they do not contradict to the rationale already given in [BSI-PP-0002] for the assumptions, policy and threats defined there.

O.SWDetect is implemented by the exception conditions recognised under FPT_FLS.1 and the opportunities provided to test for violations of secure state (or to maintain velocity check parameters) by the EEPROM write interrupts in FPT_FLS.1. As noted for O.Phys-Manipulation and O.Malfunction above, the access control provisions in FDP_ACC.1 and FDP_ACF.1 provide protection for the ways in which these detection features are used.

Revision 2.0, 23 February, 2007 Page 54 of 59

HD65256D Security Target

– Public Version

HD65256D-CC-ST-0002

O.SWResponse is implemented by the ability of Smartcard Embedded Software to cause a reset

(by setting the halt bit to halt the processor, as noted under FPT_FLS.1), and the opportunity for other protective measures as part of the EWE interrupt routines provided under FPT_FLS.1.

RE.Phase-1 contributes to OE.InjDatSupp. It is because the Smartcard Embedded Software is required by RE.Phase-1 to have a certain configuration so that the injected data shall be generated, distributed, maintained and destroyed in an adequately secure fashion.

The assignment/selection operations performed on the SFRs drawn from [BSI-PP-0002] are shown in [BSI-PP-0002] itself. The additional operations performed in this ST are as follows:

Table 8-3: Completion of SFRs

SFR Operation required Operation per for med

FCS_RND.1 [assignment: a defined quality metric] The requirements of the monobit, poker, runs, long run, and autocorrelation tests in [AIS31].

FCS_COP.1

[DES]

[assignment: list of cryptographic operations]

[assignment: cryptographic algorithm]

Encryption and decryption

DES

FDP_ACC.1

[CRP]

[assignment: cryptographic key sizes] 56 bit

[assignment: list of standards] U.S. Department of Commerce /

National Bureau of Standards

Data Encryption Standard (DES), FIPS

PUB 46-3, 1999 October 25

[assignment: access control SFP]

[assignment: list of subjects, objects, and operations among subjects and objects covered by the SFP].

Controlled-Register Policy

Any attempt to set bits in defined, security-relevant registers

FDP_ACC.1

[WPP]

[assignment: access control SFP]

[assignment: list of subjects, objects, and operations among subjects and objects covered by the SFP].

Write-Protect Policy

Software to write to EEPROM.

Revision 2.0, 23 February, 2007 Page 55 of 59

HD65256D Security Target

– Public Version

HD65256D-CC-ST-0002

SFR

FDP_ACF.1

[CRP]

FDP_ACF.1

[WPP]

Operation required

[assignment: access control SFP]

[assignment: security attributes, named groups of security attributes]

[assignment: rules governing access among controlled subjects and controlled objects using controlled operations on controlled objects]

[assignment: rules, based on security attributes, that explicitly authorise access of subjects to objects]

[assignment: rules, based on security attributes, that explicitly deny access of subjects to objects]

[assignment: access control SFP]

[assignment: security attributes, named groups of security attributes]

[assignment: rules governing access among controlled subjects and controlled objects using controlled operations on controlled objects]

None

Write-Protect Policy

The memory area to be accessed and the operation to be performed

Evaluate the corresponding permission control information: “An attempt to write to EEPROM shall fail, leaving the previous memory contents unaltered if protection is set for the relevant

EEPROM page. Once a page is writeprotected, this protection cannot be removed.” before, during or after the access so that accesses to be denied can not be utilised by the subject attempting to perform the operation

None

Operation per for med

Controlled-Register Policy

Subject: software running on the ROM

Object: control registers relating to the

FMU

Attributes: to have read and/or write access normally

Evaluate the corresponding permission control information: “The ability to set the values in the controlled registers is restricted to software operations executed from the ROM.” before, during or after the access so that accesses to be denied can not be utilised by the subject attempting to perform the operation

None

[assignment: rules, based on security attributes, that explicitly authorise access of subjects to objects]

[assignment: rules, based on security attributes, that explicitly deny access of subjects to objects]

None

8.2.1 Dependencies

The basic dependencies are shown in section 7.2.2 of [BSI-PP-0002] and are applicable to this

ST – these are summarised in the table below:

Revision 2.0, 23 February, 2007 Page 56 of 59

HD65256D Security Target

– Public Version

Table 8-4: Dependencies from [BSI-PP-0002, 7.2.2]

HD65256D-CC-ST-0002

SFR Dependencies

Fulfilled by Security Requirements in

[BSI-PP-0002]?

FRU_FLT.2

FPT_FLS.1

FPT_SEP.1

FMT_LIM.1

FMT_LIM.2

FAU_SAS.1

FPT_PHP.3

FDP_ITT.1

FDP_IFC.1

FPT_ITT.1

FCS_RND.1

FPT_FLS.1

ADV_SPM.1

None

FMT_LIM.2

FMT_LIM.1

None

None

FDP_ACC.1 or

FDP_IFC.1

FDP_IFF.1

None

None

Yes

Yes (Part of EAL4)

No dependency

Yes

Yes

No dependency

No dependency

Yes

See discussion in [BSI-PP-0002, 7.2.2]

No dependency

No dependency

The additional dependencies relating to the new SFRs introduced in this ST are analysed below.

Table 8-5: Additional SFR Dependencies

SFR Dependencies

Fulfilled by Security

Requirements in this ST?

FCS_COP.1 [DES]

FDP_ITC.1

FCS_CKM.1

FCS_CKM.4

FMT_MSA.2

FDP_ACF.1 [CRP]

FDP_ACF.1 [WPP]

[FDP_ITC.1 or FCS_CKM.1]

FCS_CKM.4

FMT_MSA.2

[FDP_ACC.1, or FDP_IFC.1]

FMT_MSA.3

FCS_CKM.4

FMT_MSA.2

[FDP_ITC.1 or FCS_CKM.1]

FMT_MSA.2

ADV_SPM.1

[FDP_ACC.1 or FDP_IFC.1]

FMT_MSA.1

FMT_SMR.1

FDP_ACC.1 [CRP] FDP_ACF.1

FDP_ACC.1 [WPP] FDP_ACF.1

FDP_ACC.1

FMT_MSA.3

FDP_ACC.1

FMT_MSA.3

Yes (by the environment)

No additional requirement – see discussion below

No additional requirement – see discussion below

No additional requirement – see discussion below

No additional requirement – see discussion below

Yes

Yes

Yes

No additional requirement – see discussion below

Yes

No additional requirement – see discussion below

The dependencies defined for FCS_COP.1 in [CC/2] are discharged by the requirements on the environment, as described in [PA].

Revision 2.0, 23 February, 2007 Page 57 of 59

HD65256D Security Target

– Public Version

HD65256D-CC-ST-0002

Hence there is no further functional requirement on the TOE arising from the dependencies of

FCS_COP.1.

The dependencies defined for FDP_ITC.1, FCS_CKM.1, FCS_CKM.4, and FMT_MSA.2 are not resolved because they will be fulfilled in the environment, where the appropriate decisions will be made.

The dependency defined for FDP_ACF.1 in [CC/2] is discharged as follows:

FDP_ACF.1 [CRP] is simply applied for the control of the access to registers, and it does not require setting of the initial value of security attributes, which is required under

FMT_MSA.3. Also, FDP_ACF.1 [WPP] simply covers the control of the access to the

EEPROM, and it also does not require setting of the initial value of security attributes, which is required under FMT_MSA.3. Therefore, the dependency on the component

FMT_MSA.3 is discharged.

The discussion in sections 8.2 and 8.3, and the rationale in section 7.2 of [BSI-PP-0002], show how the security functional requirements support each other in meeting the security objectives of this ST. Together with the discussion of dependencies above this shows that the security functional requirements build a mutually supportive whole.

8.3 TOE Summar y Specification Rationale

The table below shows the ways in which the SFRs are implemented by TOE security functions.

Table 8-6: SFR Mapping to TOE Security Functions

SFR

FRU_FLT.2

FPT_FLS.1

FPT_SEP.1

FMT_LIM.1

FMT_LIM.2

FAU_SAS.1

FPT_PHP.3

FDP_ITT.1

FPT_ITT.1

FDP_IFC.1

FCS_RND.1

FCS_COP.1 [DES]

FDP_ACC.1 [CRP]

FDP_ACC.1 [WPP]

FDP_ACF.1 [CRP]

FDP_ACF.1 [WPP]

SF.HWProtect, SF.FMU, SF.ESFunctions

SF.HWProtect, SF.FMU, SF.ESFunctions, SF.EEPAccess

SF.HWProtect, SF.FMU, SF.ESFunctions, SF.EEPAccess

SF.TestModeControl

SF.TestModeControl

SF.Inject

SF.HWProtect, SF.FMU, SF.ESFunctions

SF.LeakProtect

SF.LeakProtect

SF.LeakProtect

SF.RNG

SF.DES

SF.FMU

SF.EEPAccess

SF.FMU

SF.EEPAccess

TOE Security Function

Details of the TOE summary specification rationale are not given in this version of the Security

Target.

Revision 2.0, 23 February, 2007 Page 58 of 59

HD65256D Security Target

– Public Version

8.4

HD65256D-CC-ST-0002

Assur ance Requir ements and Str ength of Function Rationale

This ST follows the rationale given in section 7.2.3 of [BSI-PP-0002] for the choice of EAL4, assurance augmentations and the strength of function SOF-high.

8.5 Mutual Suppor t and Inter nal Consistency

The discussion of security functional requirements, TOE Summary Specification and assurance components in the sections above shows that mutual support and consistency are present for both groups of requirements. The arguments given for the adequacy of the assurance components for the TOE functionality also shows that the functional and assurance requirements support each other and that there are no inconsistencies between these groups.

For the additional functionality included in O.Add-Functions, the security functional requirements required to meet the security objectives O.Leak-Inherent, O.Phys-Probing,

O.Malfunction, O.Phys-Manipulation and O.Leak-Forced also protect the cryptographic algorithms implemented according to the security functional requirement FCS_COP.1.

Therefore, these security functional requirements support the secure implementation and operation of FCS_COP.1.

8.6 PP Claims Rationale

This ST implements all of the requirements of [BSI-PP-0002] by inclusion (as shown in each of the relevant sections), and hence no further rationale is required.

** End of Document **

Revision 2.0, 23 February, 2007 Page 59 of 59

Was this manual useful for you? yes no
Thank you for your participation!

* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project

Download PDF

advertisement

Table of contents