CACR CC Briefing

CACR CC Briefing

Stephen Booth

Computer and System Security Section

Communications Security Establishment

Stephen [email protected]

November 8, 1999 CACR Briefing 3

Presentation Objectives

• I intend to provide:– an overview of the CC Project– the Current Status of the CC and CEM– a description of the CC MRA– a high level description of the CC - how it is

structured– a description of the Canadian CC Scheme


Terms Used• CC - Common Criteria• CCEF - (CCE Approved) CC Evaluation Facility• CCS - Canadian CC Evaluation and Certification Scheme• CEM - Common Evaluation Methodology• EAL - Evaluation Assurance Level• MRA Mutual Recognition Arrangement• PP - Protection Profile ( what the buyer needs)• ST - Security Target ( what the vendor has)• TOE - Target of Evaluation (the product)• TSF - TOE Security Functions


CC PPs and STs/TOEsProtection Profile

(What I Need)

Target of Evaluation(the Product)

Security Target(What I Have)

Customer

Vendor


History of Evaluation Criteria• ‘83/85: Trusted Computer System

Evaluation Criteria (TCSEC) • ‘91: Information Technology Security

Evaluation Criteria (ITSEC)• ‘93: Canadian Trusted Computer

Evaluation Criteria (CTCPEC)• ‘96: Common Criteria (CC)


TCSEC• Trusted Computer System Evaluation

Criteria (orange book) DoD 5200.28-STD, December 1983

• Four trust rating divisions (classes): – D, C (C1, C2), B (B1, B2, B3), A (A1)

• Three basic requirements:• specific security functionality requirement• assurance requirement• documentation requirement


ITSEC• Information Technology Security Evaluation

Criteria (France, Germany, Netherlands and UK) v1.2, 1991

• focus is on assurance regardless of functionality

• product evaluated to perform as indicated in documentation


CTCPEC• Canadian Trusted Computer Product

Evaluation Criteria, Version 3.0, Jan. 1993• two types of requirements are delineated:

• functionality requirements

• assurance requirements (T-0 to T-7)

• functionality: four policy-oriented criteria - Confidentiality, Integrity, Availability and Accountability


Common Criteria (CC)• Common Criteria Version 1.0 (CC) 31 Jan 1996• aligned the evaluation criteria of nations (ie. TCSEC,

FC (USA), CTCPEC (Canada), ITSEC (Europe), ISO)• compatible with existing evaluation criteria• one product evaluated against it (Milkyway Black Hole

firewall)• CC version 2.0 (May 1998) now superceded by• CC Version 2.1 which is identical to ISO 17408


CEM

• What is the CEM?

– Common Methodology for information technology security evaluation

– An common understanding of what the CC assurance requirements mean and the minimum work necessary to satisfy them

– Supports mutual recognition of evaluation results


Purpose of the CEM

• Defines specific evaluator work units• Common approach to satisfying assurance

requirements defined in CC Part 3• Primary audience is evaluators and certifiers

overseeing evaluator work• Counter balances commercial pressures to

reduce evaluation effort


Progress to date on the CEM

• Part 1, Introduction and general model, release January 97

• Part 2, Evaluation methodology, first released January 99 (ver 0.6) (1003 comments received)

• Part 2, re-released, August 99 (ver 1.0)

– Incorporated large majority of comments

• Working document for next 12 to 18 months

• MRA requirement to use for evaluations commencing Jan 2000


Future work on the CEM• Methodology for augmentations beyond predefined

assurance packages

• Evaluations need not be performed using pre-define assurance packages

• Methodology for maintenance of certificates

• How to extend evaluation results to future releases

• Methodology for high assurance requirements

• Current CEM covers assurance requirements in low to medium assurance category


Mutual Recognition Arrangement

• attempted to document a “gentleman’s agreement” to accept each others evaluation results

• started as an agreement but that meant it was staffed and signed as an international treaty

• fundamental concept of the CC project

• if there is no effective MRA then the CC project has failed!


What do we need for MRA?

• Common and agreed upon standard

• Common and agreed upon evaluation methodology

• Trust / comfort that the other signatories are doing things if not the same way then at least in a consistent way

• Willingness of all the partners to take some risks


What do we have that let us sign MRA?

• CC

• CEM

• require evaluation facilities to be accredited to ISO 25

• require CBs to meet the requirements of ISO 65

• Technical discussion group that meets to talk about how each of our schemes work

• a commitment to undergo voluntary periodic assessments

• Are we all totally comfortable?


What do we have that let us sign MRA?

• Risk takers and mitigation steps

– accepted each other “on faith” and before CEM was completed

– we accept EAL 1 to 4 for now

• a commitment to make MRA and the CC project work


MRA Signing

• Arrangement on the Mutual Recognition of Common Criteria Certificates in the Field of Information Technology Security

– signed October 8,1998

– Germany, UK, Canada, US and France

– expanded this year (September )to include the Australasian Scheme


What does it mean?

• Extracts from the MRA document


MRA Future

• expand both signatories and scope ( >EAL 4)

• initiatives underway to expand to Europe

• work on CEM for higher assurance levels

• stepping up the schedule of “voluntary assessments”


CC Document Structure

• Part 1 Introduction and general model

• Part 2 Security functional requirements

• Part 3 Security assurance requirements


CC Part 1

• Introduction to the rest of the documents

• A general model of evaluation

• Common Criteria evaluation results

• Structure for expressing requirements and specifications


CC Part 2

• Class, family, and component structure

• Operations

• Catalogue of functional requirements

• Application notes (housed in a separate volume)


CC Part 3• Assurance requirements of the criteria:

– CC Assurance Paradigm

– Evaluation criteria for PPs (Class APE)

– Evaluation criteria for STs (Class ASE)

– Catalogue of assurance requirements

– Evaluation assurance levels (EALs)

CC Functionality


Functional Requirements

• Describe the desired security behavior of the TOE

• Intended to protect confidentiality, integrity and availability of assets, as required

• May be customized for inclusion in a PP/ST


ComponentComponent

Requirements Structure Class

FamilyFamily

ElementElement

FamilyFamily

ElementElement

ComponentComponent


Interpreting Functional Requirement Names

FIA_UID.1.2

F=FunctionalA=Assurance

SpecificClass

FamilyName

ComponentNumber

ElementNumber


CC Functional Classes (1)

• Security audit (FAU)

• Communication (FCO)

• Cryptographic support (FCS)

• User data protection (FDP)

• Identification and authentication (FIA)

• Security management (FMT)


CC Functional Classes (2)

• Privacy (FPR)

• Protection of the TOE Security Functions (FPT)

• Resource utilisation (FRU)

• TOE access (FTA)

• Trusted path/channels (FTP)


Functional Components

• It is the collection of functional components in a PP/ST that defines the functionality

• Each component contains a list of evaluatable statements, called “elements”

• All elements must be successfully evaluated within a component


FIA: Identification and authentication

• Addresses requirements for functions to establish and verify a claimed user identity

• FIA deals with:– user identification and authentication– authentication failures– user attributes (e.g., clearances, roles)– constraints on quality of authentication data

(e.g. minimum password size)


Selected FIA families

• FIA_UID: User identification

• FIA_UAU:User authentication

• FIA_SOS: Specification of secrets


FAU: Security Audit

• Security auditing involves recognising, recording, storing, and analysing information related to security relevant events.

• Post event examination of which security events took place, and which user (if applicable) is responsible.


Selected FAU families

• FAU_GEN: Security Audit Data Generation• FAU_SEL: Security Audit Event Selection• FAU_STG: Security Audit Event Storage• FAU_SAR: Security Audit Review• FAU_SAA: Security Audit Analysis


FMT: Security Management

• management of TSF data (e.g. banners)• management of security attributes (ACL’s)• management of functions of the TSF (e.g.

selection of functions, setting rules, etc.)• definition of security roles


Selected FMT families

• FMT_MSA: Management of Security Attributes– attribute: used for enforcement of TSP

• FMT_MTD: Management of TSF Data– data: created by and for the TOE

• FMT_SMR: Security Management Roles


FCO:Communications

• Address the functions that are concerned with assuring the identity of a party participating in a data exchange– proof of origin – proof of receipt


FCO Families

• FCO_NRO: Non-repudaition of origin• FCO_NRR: Non-repudiation of receipt


FDP: User data protection• Specifies requirements for policies and functions related

to user data protection• FDP deals with:

– security function policies for user data protection (access control, information flow)

– forms of user data protection– off-line storage, import and export– inter-TSF communication


Selected FDP families

• FDP_ACC: Access control policy

• FDP_ACF: Access control functions

• FDP_RIP: Residual information protection

• FDP_ROL: Rollback

• FDP_SDI: Stored data integrity


FPR: Privacy• Addresses those functions that protect

against discovery and misuse of identity by others


FPR Families• FPR_ANO: Anonymity

• FPR_PSE: Pseudonymity

• FRP_UNL: Unlinkability

• FPR: Unobservability


FRU: Resource utilization

• Supports the availability of required resources (processing capability, storage capacity)

• FRU deals with:– fault tolerance– prioritization of services– resource allocation


Selected FRU family

• FRU_RSA: Resource allocation


FPT: Protection of the TOE Security Functions

• 3 significant portions of the TSF:– abstract machine

• what does the TOE “sit upon”

– implementation• the mechanisms that enforce the TSP

– TSF data• the transient rules and data of the TOE


Selected FPT families

• FPT_FLS: Fail Secure• FPT_RCV: Trusted Recovery• FPT_RVM: Reference Mediation• FPT_SEP: Domain Separation


FTA: TOE Access

• Addresses functional requirements for controlling the establishment of a user’s session


FTA Families

• FTA_LSA: Limitation on scope of slectable attributes

• FTA_MCS: Limitation on multiple concurrent sessions

• FTA_SSL: Session locking

• FTA_TAB: TOE Access banners

• FTA_TAH: TOE Access history

• FTA_TSE: TOE Session establishment


FTP:Trusted Path/Channels

• Addresses functional requirements for – trusted communications path between users

and the TSF and– trusted channel between TSF and other

trusted IT products


FTP Families

• FTP_ITC: Inter TSF trusted channel• FTP_TRP: Trusted path

– a direct path between users and the TSF


FCS: Cryptographic support• Addresses TOEs which employ cryptographic

functionality• FCS deals with:

– cryptographic key generation, distribution, access and destruction

– cryptographic operations performed by the TOE (e.g., encryption, decryption, digital signatures, checksums, secure hash, etc.)


FCS families

• FCS_CKM: Cryptographic key management

• FCS_COP: Cryptographic operation


FCS_CKM: Cryptographic key management (1)

• This family supports the management of cryptographic keys throughout their life cycle

• Each of the components allow for claims to be made that particular standards are met

• FCS_CKM.1 requires that the TSF generate cryptographic keys; operations are completed for the key generation algorithm and key size


FCS_CKM: Cryptographic key management (2)

• FCS_CKM.2 defines how the TSF distributes cryptographic keys (operations)

• FCS_CKM.3 specifies the types of cryptographic access (with associated methods) employed by the TSF (operations)

• FCS_CKM.4 defines how the TSF destroys cryptographic keys (operations)


FCS_COP: Cryptographic operation (1)

• This family contains only one component: FCS_COP.1

• This family identifies which cryptographic operations (e.g., data encryption, digital signature) are performed by the TOE, and using which cryptographic algorithms, and key sizes


FCS_COP: Cryptographic operation (2)

• Although strength of cryptographic algorithms is outside the scope of the CC, the correct implementation of the cryptographic algorithms must still be verified by the evaluator


CC Assurance

• Configuration Management

• Delivery & Operation

• Development

• Guidance Documents

• Life Cycle Support

• Tests

• Vulnerability Assessment


Different Levels of Assurance

• The CC Provides for 7 different “Evaluation Assurance Levels” (EALs)– Starts at EAL1 (Low Assurance)– EAL3 & EAL4 (Medium Assurance)– EAL5 & EAL6 (High Assurance)– EAL7 (State of the Art)

Assurance Class AssuranceFamily

Components

EAL1 EAL2 EAL3 EAL4 EAL5 EAL6 EAL7Configuration ACM_AUT 1 1 2 2Management ACM_CAP 1 2 3 4 4 5 5

ACM_SCP 1 1 2 2 2 3Delivery & ADO_DEL 1 1 2 2 2 3Operation ADO_IGS 1 1 1 1 1 1 1

Development ADV_FSP 1 1 1 2 3 3 4ADV_HLD 1 2 2 3 4 5ADV_IMP 1 2 3 3ADV_INT 1 2 3ADV_LLD 1 1 2 2ADV_RCR 1 1 1 1 2 2 3ADV_SPM 1 3 3 3

Guidance AGD_ADM 1 1 1 1 1 1 1documents AGD_USR 1 1 1 1 1 1 1

Life cycle support ALC_DVS 1 1 1 2 2ALC_FLR (Flaw remediation procedures )ALC_LCD 1 2 2 3ALC_TAT 1 1 3 3

Tests ATE_COV 1 2 2 2 3 3ATE_DPT 1 1 2 2 3ATE_FUN 1 1 1 1 2 2ATE_IND 1 2 2 2 2 2 3

Vulnerability AVA_CCA 1 2 2assessment AVA_MSU 1 2 2 3 3

AVA_SOF 1 1 1 1 1 1AVA_VLA 1 1 2 3 4 4


Objective of EAL 1• Security requirements are traced into the design

• testing verifies behavior is as expected

• This provides assurance because;

– if a product behaves IAW with security requirements, and

– if security requirements are effective to solve security problem, then

– product will effectively solve security problem


Why EAL 1 is considered basic• So little is known about the product’s design

– correct behavior does not mean vulnerability free• Nothing is known about the development process

– poor development practices often means poor security, or

– good security cannot be assured in the absence of good development practices


EAL1 versus EAL3

• EAL1 (Low Assurance)

– “Functionally Tested”

– Given a product with Installation, Admin & User Guides.

– Does it do what the Guides said it would?

• EAL3 (Medium Assurance)

– EAL1 plus…

– High Level Design

– Test Plan, Procedures, Results, Coverage, Depth, Independent

– Misuse, SOF, Obvious Vulnerabilities


Canadian Common Criteria Evaluation and Certification

Scheme


CCS Purpose• To provide a cost effective, expandable IT

security evaluation capability in Canada• ensure quality of evaluations• improve availability of evaluated products• improve efficiency and cost effectiveness of

evaluation and certification processes


CCS Framework

• SCC Accreditation of IT E&T Facilities• CSE Approval of CCS ITSEFs >>CCEFs• CCEFs will Evaluate IT products• CSE will Certify CCEF results


General requirements for the Competence of Calibration& Testing Laboratories: ISO Guide 25, CAN-P-4

A Framework for Commercial ITS Evaluation and Testing

• Basic Quality System• Management Structure • Documented Procedures



Guidelines for the Accreditation of ITS Evaluation and Testing Facilities (CAN-P-1591)


• ITS Knowledge and Skills





CC Based

Product(Phase I)

and

System(Phase II)

Evaluationsand

Certifications

•The Canadian CCS will be the first program to build on this “foundation” in Canada



SecureElectronicBusinessTesting /

Approvals?

SystemVulnerability

Analysis?

BiometricTesting /

Approvals?CBA

Testing?



CC Based

Product(Phase I)

and

System(Phase II)

Evaluationsand

Certifications

PKI Certificate

PolicyApprovals?


CSE as the Certification Body

• approve prospective CCEFs• provide advice & guidance to the CCEFs• monitor the conduct of evaluations• certify conformance of evaluation results• provide international liaison - the MRA


Certification - 3 Pillars

• Performance of Evaluator Activities– Independently perform & compare

• Observation of Evaluator Activities– First hand observe Evaluator Activities

• Examination of Evaluation deliverables– Approval of final results (e.g. ETR, PCR)


The Big PictureVendor CCEF CCS Consumer

Produces Evaluates Certifies Acquires

IT Product& ST

IT Product& ST

EvaluationResults

Security &Assurance


Summary

• IT Products Evaluated by a Trusted & Qualified 3rd Party are of Value.

• The CC is the New World Standard (ISO 15408)

• The CCS and the CCEF’s are here today to help you acquire Security and Assurance.


Points of Contact / Info

• CSE & CCS: http://www.cse-cst.gc.ca

• SCC: http://www.scc.ca/palcan/itset.html

• EWA: http://www.ewa-canada.com/

– has evaluated at EAL1 http://www.signal9.com/

• LGS/Domus: http://www.domus.com/itss/

– is evaluating http://www.winmagic.com/product.html

• CGI: http://www.cgi.ca/e/solutions/expertise/infosecurity/

– has evaluated at EAL1 http://www.entrust.com/truedelete/index.htm


Links• Common Criteria Support Environment

– ccse.cesg.gov.uk/

• Protection Profiles - WEB site

– www.radium.ncsc.mil/tpep/library/protection_profiles

– csrc.nist.gov/cc/pp/pplist.htm

– www.cesg.gov.uk/cchtml/ippr/

• CC Resource WEB sites

– http://www.cse.dnd.ca/cse/english/cc.html

– ftp://ftp.cse.dnd.ca/pub/criteria

– http://csrc.nist.gov/cc


CSE Approved CCEFs CGI Information Systems and Management Consultants Inc. • POC: Mr Andrew Pridham Tel: (613) 234-2155• E-mail: [email protected]

DOMUS ITSL, a division of LGS Group Inc. • POC: Mr Bill Dziadyk Tel: (613) 230 - 6285• E-mail: [email protected]

EWA - Canada Ltd, • POC: Mr Paul Zatychec Tel: (613) 230 - 6067 Ex. 227• E-mail: [email protected]

•


Questions?