Prox-RBAC: A Proximity-based Spatially Aware RBAC Michael S. - - PowerPoint PPT Presentation

Prox-RBAC: A Proximity-based Spatially Aware RBAC

Michael S. Kirkpatrick Maria Luisa Damiani Elisa Bertino 19th ACM SIGSPATIAL International Conference on Advances in Geographic Information Systems (GIS) Chicago, IL, USA November 4, 2011

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Motivation

2

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Motivation

2

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Motivation

2

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Motivation

• GEO-RBAC augments access control with

spatial data

• <Doctor, coffeeshop> vs. <Doctor, ER>
• Spatial role based on requesting user’s location
• Others’ locations have security implications
• Separation of duty
• Presence of unprivileged users (e.g., civilians)

3

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Motivation

• GEO-RBAC augments access control with

spatial data

• <Doctor, coffeeshop> vs. <Doctor, ER>
• Spatial role based on requesting user’s location
• Others’ locations have security implications
• Separation of duty
• Presence of unprivileged users (e.g., civilians)

3

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Key Issues

• Space model
• Language definition
• Location integrity
• Technological feasibility

4

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Key Issues

• Space model
• Language definition
• Location integrity
• Technological feasibility

4

GIS Access Control Crypto Formal Methods/ Languages This talk

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Space Model

5

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Space Model

5

• Indoor space model
• Protected area (PA)
• Entry points

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Space Model

5

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Space Model

6

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Space Model

6

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Space Model

6

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Accessibility Graph

• Directed multigraph
• Nodes denote protected

areas

• Edges denote entry points

7

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Hierarchical Containment

• Partial order pai ⊆ paj
• s ∈ pai ⇒ s ∈ paj
• Entry into pai requires presence in paj
• pai ⊆ paj and pai ⊆ pak ⇒ paj ⊆ pak or pak ⊆ paj

8

Π Π Π Π Π

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Parent Tree

9

• Accessibility graph alone is

insufficient

• Hierarchical space model
• Typing of areas
• Room, floor, suite, etc.
• User locations are at finest

granularity

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Authorized PAs

• AuthPA(s)
• PAs subject s is authorized to enter
• pai ∈ AuthPA(s) implies Parent(pai) ∈ AuthPA(s)
• If pai ∈ AuthPA(s) and pai only reachable from

sibling paj, then paj ∈ AuthPA(s)

10

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Authorized PAs

• AuthPA(s)
• PAs subject s is authorized to enter
• pai ∈ AuthPA(s) implies Parent(pai) ∈ AuthPA(s)
• If pai ∈ AuthPA(s) and pai only reachable from

sibling paj, then paj ∈ AuthPA(s)

10

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Authorized PAs

• AuthPA(s)
• PAs subject s is authorized to enter
• pai ∈ AuthPA(s) implies Parent(pai) ∈ AuthPA(s)
• If pai ∈ AuthPA(s) and pai only reachable from

sibling paj, then paj ∈ AuthPA(s)

10

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Policy Language

11

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Policy Language

11

• Relative constraint clause
• Continuity of usage
• Timeout constraint

at_least 1 supervisor in Room 100 while (at_most 0 civilians in this.room) while (...) timeout 1 minute

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Policy Language

11

• Relative constraint clause
• Continuity of usage
• Timeout constraint

at_least 1 supervisor in Room 100 while (at_most 0 civilians in this.room) while (...) timeout 1 minute

Any topological relationship

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Policy Language

11

• Relative constraint clause
• Continuity of usage
• Timeout constraint

at_least 1 supervisor in Room 100 while (at_most 0 civilians in this.room) while (...) timeout 1 minute

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Policy Language

11

• Relative constraint clause
• Continuity of usage
• Timeout constraint

at_least 1 supervisor in Room 100 while (at_most 0 civilians in this.room) while (...) timeout 1 minute

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Policy Language

11

• Relative constraint clause
• Continuity of usage
• Timeout constraint

at_least 1 supervisor in Room 100 while (at_most 0 civilians in this.room) while (...) timeout 1 minute

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Semantics

12

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Semantics

12

User is in the PA, authorized to enter role

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Semantics

12

Other users also satisfy constraints

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Semantics

12

... Access stopped when others move

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Enforcement

13

AS

LD LD LD LD LD LD LD LD LD

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Enforcement

13

AS

LD LD LD LD LD LD LD LD LD

Proof of location

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Enforcement

13

AS

LD LD LD LD LD LD LD LD LD

Proof + credentials

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Request Protocol

14

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Request Protocol

14

Bind the user to the location at the time

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Request Protocol

14

Send request and signed commitment

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Request Protocol

14

Prove commitment matches

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Implementation

• Cryptographic protocols
• Feige-Fiat-Shamir proves identity in ZK
• Pedersen commitment binds user
• SHA-256, AES, RSA, DSA for hash, encrypt, sign
• NFC for proximity control
• Must connect twice

15

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Implementation

16

AS

LD LD

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Implementation

16

AS

LD LD

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Implementation

16

AS

LD LD

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Implementation

16

AS

LD LD

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Implementation

16

AS

LD LD

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Future Work

• Formal notion of proximity
• Reconcile Prox-RBAC with GEO-RBAC
• Alternative movement monitoring
• Location privacy

17

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011

Acknowledgments

18

This work has been partially supported by Sypris Electronics and by the MURI award FA9550-08-1-0265 from the Air Force Office of Scientific Research.

Wednesday, November 9, 2011

• M. S. Kirkpatrick, M. L. Damiani, E. Bertino

Prox-RBAC: A Proximity-based Spatially Aware RBAC ACM GIS 2011 19

Thanks!

Wednesday, November 9, 2011