Re-using existing PKIs for online Identity Management Martijn Oostdijk Novay 22/10/09 | Session ID: 305 Classification: Intermediate

Agenda Electronic Passports A short introduction to Identity 2.0 Using the ePassport PKI for online IdM Conclusions

How to apply what you learn here? I will demonstrate how third parties (you?) can piggyback “traditional” PKI infrastructure to facilitate your organization’s IdM You are invited to come and discuss pros and cons of the combination of PKI and user-centric IdM You will understand the risks involved and benefits of this combination, and be able to judge whether it is cost-effective for your organization Educate + Learn = Apply

I will demonstrate how third parties (you?) can piggyback “traditional” PKI infrastructure to facilitate your organization’s IdM

You are invited to come and discuss pros and cons of the combination of PKI and user-centric IdM

You will understand the risks involved and benefits of this combination, and be able to judge whether it is cost-effective for your organization

An Introduction to Identity 2.0

Web / Identity 2.0 means… “ Everybody knows you’re not a dog.”

“ Everybody knows you’re not a dog.”

An attempt to define “Identity” Identity is what you and others claim about you In real life, whether you trust a claim Depends on context, Depends on “authorities” or “Identity Providers” parents, school, government Depends on “Identity Providers by proxy” signed note, diploma, passport, driver’s license On the Internet there is little context Identity Providers needed for trust

Identity is what you and others claim about you

In real life, whether you trust a claim

Depends on context,

Depends on “authorities” or “Identity Providers”

parents, school, government

Depends on “Identity Providers by proxy”

signed note, diploma, passport, driver’s license

On the Internet there is little context

Identity Providers needed for trust

Identity Management Would like to use service Facilitates this process by - checking credentials of C - controlled release of attributes about C Client (C) Relying Party (RP) Identity Provider (IdP)

Online or offline IdP? Online IdP Redirect RP to IdP Drawback: single point of failure Drawback: infrastructure cost Drawback: privacy? Offline IdP IdP signed an identifier for client to present to RP No single point of failure Drawback: revocation No need to trust IdP w.r.t. privacy Drawback: can we trust user / user’s PC to store identifier?

Online IdP

Redirect RP to IdP

Drawback: single point of failure

Drawback: infrastructure cost

Drawback: privacy?

Offline IdP

IdP signed an identifier for client to present to RP

No single point of failure

Drawback: revocation

No need to trust IdP w.r.t. privacy

Drawback: can we trust user / user’s PC to store identifier?

What is Identity 2.0? Identity 2.0 is User-centric Identity The user is in control over what information is shared with RP Two standards are popular: OpenID Information Card Hot or hype? (Like everything 2.0?) We’ll focus on Information Card here

Identity 2.0 is User-centric Identity

The user is in control over what information is shared with RP

Two standards are popular:

OpenID

Information Card

Hot or hype? (Like everything 2.0?)

We’ll focus on Information Card here

Laws of Identity 2.0 By Kim Cameron of Microsoft User control Minimal disclosure, constrained purpose Justifiable parties Directed identity Pluralism of operators and technologies Human integration Consistent experience across contexts Explained for dummies: People using computers should be in control of giving out information about themselves, just as they are in the physical world. The minimum information needed for the purpose at hand should be released, and only to those who need it. Details should be retained no longer than necesary. It should NOT be possible to automatically link up everything we do in all aspects of how we use the Internet. A single identifier that stitches everything up would have many unintended consequences. We need choice in terms of who provides our identity information in different contexts. The system must be built so we can understand how it works, make rational decisions and protect ourselves. Devices through which we employ identity should offer people the same kinds of identity controls - just as car makers offer similar controls so we can all drive safely.

By Kim Cameron of Microsoft

User control

Minimal disclosure, constrained purpose

Justifiable parties

Directed identity

Pluralism of operators and technologies

Human integration

Consistent experience across contexts

Explained for dummies:

People using computers should be in control of giving out information about themselves, just as they are in the physical world.

The minimum information needed for the purpose at hand should be released, and only to those who need it. Details should be retained no longer than necesary.

It should NOT be possible to automatically link up everything we do in all aspects of how we use the Internet. A single identifier that stitches everything up would have many unintended consequences.

We need choice in terms of who provides our identity information in different contexts.

The system must be built so we can understand how it works, make rational decisions and protect ourselves.

Devices through which we employ identity should offer people the same kinds of identity controls - just as car makers offer similar controls so we can all drive safely.

Information Card Open standard (sort of) Self-signed cards: Attributes kept at client Managed cards: Attributes kept at IdP Windows CardSpace is Microsoft’s implementation To prevent phishing: GUI dialog leaves context of OS

Open standard (sort of)

Self-signed cards: Attributes kept at client

Managed cards: Attributes kept at IdP

Windows CardSpace is Microsoft’s implementation

To prevent phishing: GUI dialog leaves context of OS

Electronic Passports

e Passport Issued by government, standardized by ICAO Contains chip with Information about card holder Mechanism to verify integrity of that information Mechanism to verify authenticity of chip Mechanism to communicate confidentially Tested and found “secure” up to EAL4+ Intended for verification by border official’s equipment (Not intended for online verification)

Issued by government, standardized by ICAO

Contains chip with

Information about card holder

Mechanism to verify integrity of that information

Mechanism to verify authenticity of chip

Mechanism to communicate confidentially

Tested and found “secure” up to EAL4+

Intended for verification by border official’s equipment

(Not intended for online verification)

e Passport Chip Logo MRZ Antenna

Logical Data Structure hashes DGs + signature issuing state SOd public key for Active Authentication DG15 [some people with really long names] [ DG11 ] photo face DG2 name, etc, a.o. date of birth and BSN DG1 index of DGs present COM

ePassport security mechanisms CONTROLS: Basic Access Control Passive Authentication Active Authentication Extended Access Control Biometry THREATS: Skimming & tracking (privacy) Eavesdropping (privacy) Altering (authenticity, integrity) Cloning (authenticity) Disclosure of biometrics (confidentiality) Look-a-like fraud

CONTROLS:

Basic Access Control

Passive Authentication

Active Authentication

Extended Access Control

Biometry

THREATS:

Skimming & tracking (privacy)

Eavesdropping (privacy)

Altering (authenticity, integrity)

Cloning (authenticity)

Disclosure of biometrics (confidentiality)

Look-a-like fraud

e Passports form a worldwide PKI! Passive authentication means: Data groups signed by “document signer” Document signer’s certificate signed by “country signer” Country signer’s certificate is given to other countries so that they can verify integrity and authenticity Sometimes on government’s web site In that case, third parties can read content after performing BAC Can ePassports be used in Identity 2.0 scheme such as Information Card?

Passive authentication means:

Data groups signed by “document signer”

Document signer’s certificate signed by “country signer”

Country signer’s certificate is given to other countries so that they can verify integrity and authenticity

Sometimes on government’s web site

In that case, third parties can read content after performing BAC

Can ePassports be used in Identity 2.0 scheme such as Information Card?

Using the ePassport PKI for online IdM

ePassport + CardSpace

Information Card protocol 1. Access 2. Policy 3. Filter cards 4. Select card 5. Request token 6. Give token 7. Give token 5/6. BAC + AA + DG1 + DG15 + SOd IdP Client RP User

Result An online IdP can verify a user’s ePassport remotely If the ePassport supports Active Authentication, and Basic Access Control (and BAC keys known to the IdP), and the country signing certificate is known to the IdP If data is protected by EAC ePassport issuing countries can limit access to selected IdPs The IdP can translate attributes To protect privacy E.g. date-of-birth becomes “currently over 18 years of age” User still in control of what gets sent to RP

An online IdP can verify a user’s ePassport remotely

If the ePassport supports Active Authentication,

and Basic Access Control (and BAC keys known to the IdP),

and the country signing certificate is known to the IdP

If data is protected by EAC

ePassport issuing countries can limit access to selected IdPs

The IdP can translate attributes

To protect privacy

E.g. date-of-birth becomes “currently over 18 years of age”

User still in control of what gets sent to RP

Conclusions

Conclusions Trend: Identity 2.0 (user-centric) Trend: governments rolling out massive worldwide PKI Such a PKI is very 1.0, but can be used in an Identity 2.0 scheme Although role of IdP is somewhat different: A trusted online IdP is good for privacy IdP translates “raw” attributes (such as date-of-birth) to more privacy friendly attributes (such as “currently over 18 years of age”) Combining offline and online identity management offers some flexibility in terms of privacy protection

Trend: Identity 2.0 (user-centric)

Trend: governments rolling out massive worldwide PKI

Such a PKI is very 1.0, but can be used in an Identity 2.0 scheme

Although role of IdP is somewhat different:

A trusted online IdP is good for privacy

IdP translates “raw” attributes (such as date-of-birth) to more privacy friendly attributes (such as “currently over 18 years of age”)

Combining offline and online identity management offers some flexibility in terms of privacy protection

Questions?