donkey project technologies and target applications march 6, 2003, vrije universiteit yuri demchenko

Donkey Project

Technologies and Target applications

March 6, 2003, Vrije UniversiteitYuri Demchenko <[email protected]>

©February 21, 2003. Amsterdam. Donkey Project Slide2_2

Outlines

Problems in traditional PKI and Identity Management Donkey goals and functionality Design issues Timetable and Next steps Discussion:

Using and extending Donkey functionality Possible applications

Reference information


Donkey Goal(s)

Open extendable system for public key and Identity management

Initial stage

Open global distributed system for publishing and retrieving named, signed public keys

Intended development

Identity management for federated cross-domain AuthN and AuthZ

Donkey website: http://www.nlnetlabs.nl/donkey/


What is Donkey: Donkey functionality

Donkey allows anyone to publish a named key, together with optional data (Donkey package)

Multiple parties are allowed to publish a key with the same name. Applications must select the correct key when multiple keys match

Donkey is NOT a permanent storage: key must be republished to remain available

Donkey does NOT define a policy for key/payload usage – This is an application specific function

Donkey allows anyone to query for a published key, based on the key's name (required) and signers (optional)

Donkey allows anyone to sign a published key


Design issues: Package structure

(Proprietary) Internal format (Python data object) but XML based exchange format Package ID Content

Header– Flags– Names

Owner Public Key– <Name, Owner Key> must be unique

Body– Payload

• Application dependent content and format• Intended for AA and Identity management • May include specific format definition (e.g., embedded XML Schema)

Signatures


Design considerations

Build upon existing solutions and standards But still capable to do a low start

Gradual development Build up upon key storage/management engine

XML for package extensibility and exchange Including prospective use of the XML Protocol


Donkey Project milestones

Overview and inventory/planning - current stage Selected basic technologies and development environment Overview document

March-April: Prospective applications area overview Requirements (common and specific for applications) Draft Protocol description/definition

April-May: API(s) definition and Donkey prototyping API requirements

June-August: Development and pilot implementation for 1-2 applications


Donkey current status

Just started work on Donkey prototype Key generation (DSA or RSA keys) Creating a new Donkey package Add and verify signature to/of an existing Donkey package Data model and XML DTD/Schema for Donkey packages

Goal: Create a base for experiments with application specific payloads


Some specific next tasks

Overview of existing solutions for AA and Identity management Analysis of applications specific requirements

OpenPGP Keyserver Attribute/Privilege storage Identity/Credentials Storage

Trust analysis Threats analysis


Donkey functionality for AuthN/AuthZ

Donkey will be built upon existing PKI and AA applications:

• PGP Key Server

• Internet2 PubCookie/WebISO and Shibboleth/AA

• PAPI (AuthZ and Web SSO)

• A-Select (AuthZ and Web SSO)

• PERMIS (PrivilEge and Role Management Infrastructure Standards Validation Project)

• Akenti (cross-domain AA for Grid applications)


Standards for security assertions

• PGP

• X.509 Public Key Certificate (PKC)

• X.509 Attribute Certificate (AC) for Privilege Management

• SAML (Security Assertion Mark-up Language)

• Liberty Alliance Network Identity (XML and SAML based)

• Web Services Security (SOAP Extensions)


Problems in PKI and Identity Management

X.509 PKI is a heavy-weight solution and usually enterprise oriented: Requires Certificate Authority (CA) to create and trust a certificate (PKC) Certificate creation/revocation mechanism is complex, slow and expensive LDAP as a standard mechanism to publish X.509 Certs is not easily extensible

and (generically) not globally scaled

Distributed applications and mobile users require secure remote access to electronic credentials and identity information

P2P networks normally (based on DHT) require non-hierarchical (non-PKI) security infrastructure

Advent of XML/SOAP based standards for SSO/Identity management creates technological alternative for traditional PKI and PMI


Donkey and DNSSEC

DNSSEC can be a source of public keys for zones/nodes but it's not intended to provide this service for other applications: Intended for host names, not arbitrary names Updates are slow (propagation through caches, administrative overhead) Requires DNSSEC protocol for public key access/request (standard request for

KEY and SIG RRs)

Donkey can provide (shadow/alternative) key distribution infrastructure using application specific protocols to off-load DNSSEC


Identity management and SSO

Two Identity standards Microsoft passport – deployed since 2000 Liberty alliance – emerging, deployment 2003


Microsoft Passport

Proposed as a solution for Internet-wide Credentials management and Authentication service

Recently proposed Passport Manager Licensing Program Allows access to and use of Passport Manager source code to develop, debug and

support both commercial and noncommercial software for the purpose of integration

Passport Password Quality Meter tools to gauge and improve the strength of their Passport password

Next Step for the Industry: Federated Security and Identity Federated security is the ability for sites, services and applications

to safely accept and recognize identities and authentication assertions issued by any one of a trusted set of partners

Based on industry emerging Web Services Security


Securely available credentials

Obvious need for such a service Mobile users/agents Persistent storage of valuable information Scope of former IETF SACRED WG Intersects with Identity management

Required functionality Use/integrate/interchange credentials from different appliances (Internet,

mobile telephone, smartcard/bankcard, etc.) Credentials server vs direct access to home storage of credentials Technology (storage and protocol) must be opaque to credentials Need to support different types of user authentication Primary and secondary credentials vs credentials delegation


Liberty Identity and Protocol

Liberty is a set of protocols that collectively provide a solution for identity federation management, cross-domain authentication, and session management. The Liberty architecture contains three actors: Principal, identity

provider, and service providerLiberty protocol provides federation of Principal’s identity

between the identity provider and the service provider. Principal is authenticated to the identity provider Identity provider provides an authentication assertion to the

Principal Principal can present the assertion to the service provider

Principal is then also authenticated to the service provider if the service provider trusts the assertion.

An identity federation is said to exist between an identity provider and a service provider when the service provider accepts authentication assertions regarding a particular Principal from the identity provider


Reference information

PKI Basics X.509 Public Key Certificate (PKC) X.509 Attribute Certificate (AC) Role Based Access Control (RBAC)


Reference: PKI Basics

PKI - Public Key Infrastructure Binds subject’s distinguished name or identity with his/her public key The major component of PKI is Public Key Certificate (PKC)

CRL – Certificate Revocation List as a component of PKC management

PKI components Identification Service (IS) Registration Authority (RA) Certification Authority (CA) Certificate Repository (CR), normally built on LDAP


Reference: PKC vs AC: Purposes

X.509 PKC binds an identity and a public key AC is a component of X.509 Role-based PMI (Privilege Management

Infrastructure) AC contains no public key but it is issued to particular subject identified by DN AC may contain attributes that specify group membership, role, security clearance,

or other authorisation information associated with the AC holder Analogy: PKC is like passport, and AC is like entry visa

PKC is used for Authentication and AC is used for Authorisation AC may be included into Authentication message

PKC relies on Certification Authority and AC requires Attribute Authority (AA)


PKC vs AC: Certificates structure

X.509 PKC Version Serial number Signature Issuer Validity Subject Subject Public key info Issuer unique identifier Extensions

AC Version Holder Issuer Signature Serial number Validity Attributes Issuer unique ID Extensions


X.509 PKC Fields and Extensions – RFC 3280

X.509 PKC Fields Serial Number Subject Subject Public Key Issuer Unique ID Subject Unique ID

X.509 PKC Extensions Standard Extensions

Authority Key Identifier Subject Key Identifier Key Usage Extended Key Usage CRL Distribution List Private Key Usage Period Certificate Policies Policy Mappings Subject Alternative Name Issuer Alternative Name Subject Directory Attributes Basic Constraints Name Constraints

X.509 PKC Fields Private Extensions

Authority Information Access Subject Information Access

Custom Extensions


AC Attribute Types and AC Extensions

AC Attribute Types Service Authentication

Information Access Identity Charging Identity Group Role Clearance Profile of AC

AC Extensions Audit Identity

To protect privacy and provide anonymity

May be traceable via AC issuer

AC Targeting Authority Key Identifier Authority Information Access CRL Distribution Points


Role Based Access Control (RBAC)

RBAC – Role Based Access Control Role describes the function Rights define access to the resource in a specific mode under specific conditions

Benefits of RBAC Easy manage and control Seperate definition of role-user and role-privilege Scaleability Support of least privilege [rinciple Enheritance and aggregation of privileges and rights Possibility to delegate


Proxy Certificate Profile

Impersonation – used for Single-Sign-On and Delegation Unrestricted Impersonation Restricted Impersonation defined by policy

Proxy with Unique Name Allows using in conjunction with Attribute Cert Used when proxy identity is referenced to 3rd party, or interact with VO policy

Limited validity time – approx. 24 hours

Proxy Certificate (PC) properties: It is signed by either an X.509 End Entity Certificate (EEC), or by another PC.

This EEC or PC is referred to as the Proxy Issuer (PI). It can sign only another PC. It cannot sign an EEC. It has its own public and private key pair, distinct from any other EEC or PC. It has an identity derived from the identity of the EEC that signed the PC. Although its identity is derived from the EEC's identity, it is also unique. It contains a new X.509 extension to identify it as a PC and to place policies on

the use of the PC. This new extension, along with other X.509 fields and extensions, are used to enable proper path validation and use of the PC.

donkey project technologies and target applications march 6, 2003, vrije universiteit yuri demchenko

Documents

donkey functionality

donkey project slide2

available u donkey

donkey project technologies

new donkey package

donkey current status

signers optional donkey

authz donkey website