Tera Grid Plans for Authentication and Authorization Testbed

Tera. Grid Plans for Authentication and Authorization Testbed Von Welch, NCSA Science Gateway Call October 6, 2006 University of Illinois at Urbana-Champaign National Center for Supercomputing Applications

Workshop • Workshop on Tera. Grid Authentication, Authorization, and Account Management - August 30 -31, 2006, Argonne National Laboratory – Organizers: Von Welch, Tony Rimovsky, Jim Marsteller, Carolyn Peters, Dane Skow • Attendees: 42 persons, representatives from all Tera. Grid Resource Provider sites, OSG, Internet 2, Globus • http: //www-fp. mcs. anl. gov/tgmeeting/AAA-Agenda. htm • Whitepaper (Von Welch, Ian Foster, Tom Scavo, Frank Siebenlist, Charlie Catlett) http//gridshib. globus. org/tg-paper. html National Center for Supercomputing Applications

Authentication vs Authorization • Identifier: A unique name for an entity – (username, DN, GUID, SSN, etc. ) • Authentication: Verifying Identity of users – associating them with a Identifier Authorization: Deciding whether or not a request will be granted – Different authentication methods have different levels of certainty • Authorization Policy: The set of rules by which an authorization decision is made • Authentication does not imply Authorization – E. g. just because you trust a CA doesn’t mean all the user with certificates from it are authorized National Center for Supercomputing Applications

Attributes • Attribute: A property of an entity – Entities may have lots of properties – The same property may apply to many entities – E. g. community membership, affiliation, age, gender, height, occupation • Attribute-based authorization: Authorization based on who someone is (their identity) but what they are (their attributes) – E. g. you can buy me a beer if your age > 21 years National Center for Supercomputing Applications

Authorization Status Quo • Currently solely ID based – • A user has only one mapping in the system • • no capability for roles Single group membership Need prior knowledge of group membership – Maintenance /synchronization problem • No differentiation between services for access levels – – – • Allocated users Authenticated users TG Community users Partner/Campus users Public Scaling – Workload scales by ID not by group – Adds new sources of authority to manage National Center for Supercomputing Applications

Account Management Status Quo • Single Account/authorization doesn’t map to rich set of services • Persistent Execution Environments – Pre-provisioning individual environments (accounts) has large overhead and vulnerabilities – Shared environments – Environment configuration for groups must be independently duplicated • Traceable actions – Need to preserve connection from actions (and costs) to individual initiating the action for troubleshooting National Center for Supercomputing Applications

Operational Example • Number and Levels of Credentials – Resource specific (login) credentials • • • Direct machine logins Tera. Grid webpages Tera. Grid forum – Grid service credentials • • • Users internal Tera. Grid X 509 credentials (from kx 509, My. Proxy, etc) Gateway/broker credentials User’s external x 509 credentials (from DOEGrids, etc) – Gateway community credentials • • Portal login/password Home institution credentials – Commercial credentials • Scale of compromise recovery effort is large – Single general server compromise 1000 s of credentials National Center for Supercomputing Applications

Authentication Process Today • User and RP share a secret. – RP authoritative itself • Maintains contact information – User <-> RP correction relationship – Individual traceability * • CAs issue identify credentials – – – RP can validate credentials (trusting CA) CA maintains contact information (maybe) Typically not available to RP CA has loose relation to user User <-> CA <-> RP correction relationship Individual traceability * * Provided there’s no collusion National Center for Supercomputing Applications

Future • User authenticates to local institution/authority, – authority vouches for user (by constructing appropriate attributes in credential) – – – RP can validate authority attribute and binding to request (? ) RP may itself be a local institution Local institution maintains contact information with user Hierarchies allowed (ala bond brokers) Individual traceability (maybe pseudonymous) National Center for Supercomputing Applications

Individual User Environment O(10) O(1) Resource (G)Id uid uid O(1000) TGCDB project O(10) Use cases: Traditional users, Development Grant Process National Center for Supercomputing Applications

Authenticated User Environment O(10) O(1) (G)Id O(1) Resource O(10) ? uid O(1) TGCDB project O(10) Use cases: Grid-savvy user communities, Production runs, user managed services Grant Process National Center for Supercomputing Applications

Gateway Environment O(10) O(100 -10 O(1) ? 6) ? Com. Id Gateway O(10) O(100) O(1000) Resource TGCDB GId O(100) O(1) ? ? uid O(1) project O(10) O(100) Use cases: Large communities of users, novice users, public Grant Process National Center for Supercomputing Applications

Community Gateway Accounts • Shift authentication and authorization from RP to the Science Gateway • Whole community then appears as “one” user to the RP in terms of authorization – One grid-mapfile and /etc/password entry • or perhaps (a mapped set of) virtual machine images – Except accounting and troubleshooting. We still need an individual identifier National Center for Supercomputing Applications

The Proposal • Plan for a world where users can be authenticated via their home campus identity management system • Enable attribute-based authorization of users by RP site – Allow for user authentication with authorization by community • Prototype system in testbed, with involvement of interested parties to work out issues • All usage still billed to an allocation – Community or individual National Center for Supercomputing Applications

Testbed National Center for Supercomputing Applications

Testbed Components • Enhanced CTSSv 3 stack – Existing GT component extensions to enable attribute-based authorization • Identify testbed resources – UChicago/ANL, NCSA Mercury, ORNL • – Use OSG/TG VOMS test server Handful of user communities – Science Gateway, Educational, OSG, others TBD. • Use of Shibboleth and related software – my. Vocs, Grid. Shib – Leverage In. Queue/Test. Shib, UT Fed National Center for Supercomputing Applications

Must keep this tied to users • Has potential to suffer from “copper plumbing” syndrome - better infrastructure without obvious user benefit • Identify a small number of target communities to participate in testbed – Need right combination of Shibboleth deployment and Tera. Grid interest National Center for Supercomputing Applications

Testbed Use Cases 1. 2. 3. 4. 5. 6. 7. Individual New User Individual Existing User Access Shibboleth authentication to Gateway attribute authorization to RP Use Case OSG/VOMS access Educational Access Incident Response National Center for Supercomputing Applications

Individual New TG User • Registration process here… – Campus id gets into TGCDB as part of process – Utilize Shibboleth tooling for Registration process • User authenticate with campus credentials – Gets short-lived X 509 credential with DN based on Shibboleth-provided Id – With campus attributes – No TG attributes (maybe project in future? ) • User access via gsi-ssh, GRAM, gridftp – X 509 cred w/attributes presented to RP – DN+attribute registration matched to local UID through gxmap (mod) • RP does authorization based on DN – Provisioning may use attribute common set (TBD) – TP logs other attributes National Center for Supercomputing Applications

Identifying Key Communities • Large enough to suffer scaling problems – So there’s a payoff for the work • • Feasibly represented by Shibboleth or VOMS in the next 2 years Or represented by a persistent attribute authority (e. g. a Gateway) – So that it’s not yet another security system • Some subset of community represented now – So that there’s someone to work with in evaluating the use cases National Center for Supercomputing Applications

Technical and Policy Issues to be Resolved (a subset) • What identifiers and attributes are needed by Tera. Grid from campuses? • How will other attributes be sourced? E. g. Gateway communities. • Policy distribution mechanisms – Consistent TG-wide policy vs Site autonomy • Agreement between Tera. Grid and campuses providing attributes • Identify issues related to forensics/incident response and accounting • Scaling issues with key services National Center for Supercomputing Applications

Issues which will remain challenges • Numerous, small, dynamic VOs will remain difficult to support – This is key to capturing the ultimate vision of grid as infrastructure • Policy rules (expression and interpretation) remain terra incognita – There are grammars and engines, but little operating experience • Scaling growth in number of authorities needs improvement – Lessons to be learned from DNS National Center for Supercomputing Applications

Phased Deployment 1. Enable logging of attributes through the system – 2. Enable group membership decisions based on attributes – 3. Improves traceability and prepares for attribute handling Provides for community based authorization Enable attribute based authorization/provisioning decisions – – Enables user mapping to different environments Enables specialized provisioning by attribute set National Center for Supercomputing Applications