1. University of Nijmegen Jaap-Henk Hoepman Department of Computer Science University of Nijmegen, the Netherlands jhh@cs.kun.nl www.cs.kun.nl/~jhh Secure Method Invocation in JASON

2. 21-11-2002J.H. Hoepman Secure Method Invocation in JASON 2 ContentsContents  JavaCard: Promises and Problems  JASON vision  JASON secure method invocation  Discussion

3. 21-11-2002J.H. Hoepman Secure Method Invocation in JASON 3 JavaCard: Promises and Problems  Promises  Object oriented programming of smart card applications  Better chance of application separation through Java Virtual Machine  Problems  Object orientation invisible outside smart card. Still the same paradigm: Select application Send APDU command

4. 21-11-2002J.H. Hoepman Secure Method Invocation in JASON 4 JASON Vision  Objectives  Viewing a smart card system as a collection of named, networked, objects  Truly object-oriented smart card programming  Automatically enforce security requirements at method granularity as specified by programmer “Javacards As Secure Objects Network” …towards a smart card OS…

5. 21-11-2002J.H. Hoepman Secure Method Invocation in JASON 5 Related work  JCCAP (VandeWalle)  Capability based access control  VISA Open Platform Specification  Secure loading, installation and deletion of smart card applications  PC/SC / OpenCard  Transparently handle multiple smart cards  JiniCard  Download terminal plugins to accept any smart card

6. 21-11-2002J.H. Hoepman Secure Method Invocation in JASON 6 JASON Secure Method Invocation  Role based access control  Independent, per method  Role = ownership of key  Protecting parameters and results  Confidentiality  Authenticity Integrity no-replay

7. 21-11-2002J.H. Hoepman Secure Method Invocation in JASON 7 JASON Architecture dispatcher APDU dispatcher terminalcard keys skel capplet stub

8. 21-11-2002J.H. Hoepman Secure Method Invocation in JASON 8 Generating stubs/skeleton  JASON Definition File  JAVA Interface  Specify roles at start of class file  Extra keywords accessible to authentic confidential “ JASON definition file JASON definition file compiler java stub java stub java skeleton java skeleton

9. 21-11-2002J.H. Hoepman Secure Method Invocation in JASON 9 Example: specifying a purse public interface Purse { roles: BANK, MERCHANT, OWNER ; accessible to ALL: confidential authentic short getBalance () ; accessible to MERCHANT authentic void decreaseBalance ( authentic short amount ) ; accessible to BANK authentic void increaseBalance ( confidential authentic short amount ) ; }

10. 21-11-2002J.H. Hoepman Secure Method Invocation in JASON 10 The authentic keyword  Guarantees  Authenticity  Integrity  Freshness No replay  For results  It guarantees that the called method was actually executed at this time in the proper way with the intended side effect cf. a decrease purse command

11. 21-11-2002J.H. Hoepman Secure Method Invocation in JASON 11 Example: calling a purse try { Purse purse = (Purse) SMINaming.connect("smi://smartcard/Purse", Purse.MERCHANT, purseKeyStore) ; try { purse.decreaseBalance(10); System.out.println("You have paid"); } catch (UserException ue) { System.out.println ("Transaction failed. You have not paid."); } catch (RemoteException re) { System.out.println("Failed to connect to service."); }

12. 21-11-2002J.H. Hoepman Secure Method Invocation in JASON 12 Behind the scenes (1)  Connect(, )  Negotiate ciphers  Authenticate caller role  Establish authenticated caller/callee id’s  Exchange session keys privately  Return handle of skeleton

13. 21-11-2002J.H. Hoepman Secure Method Invocation in JASON 13 Behind the scenes (2)  Method call  stub converts call to secured APDU stream (only when necessary) Using session keys and message counters  Dispatcher forwards APDU stream to skeleton  skeleton verifies/decrypts parameters and calls method

14. 21-11-2002J.H. Hoepman Secure Method Invocation in JASON 14 Behind the scenes (3)  Cryptography  Keys in separate key file  Authentication based on Public key crypto (Diversified) symmetric key crypto Determined by key type in key file  Symmetric session keys

15. 21-11-2002J.H. Hoepman Secure Method Invocation in JASON 15 Behind the scenes (4)  Efficient protection by reshuffling

16. 21-11-2002J.H. Hoepman Secure Method Invocation in JASON 16 SMI vs RMI… SMI RMI SMI stub RMISMI stub or

17. 21-11-2002J.H. Hoepman Secure Method Invocation in JASON 17 DiscussionDiscussion  SMI Extensions  Transaction support  Transaction tickets  Logging & auditing  Naming and brokerage  Not finalised yet  Multi-threading method calls  Outbound calls too  JASON not limited to smart cards  Client-server  Embedded/Ambient systems

18. 21-11-2002J.H. Hoepman Secure Method Invocation in JASON 18 Closing remarks  http://www.cs.kun.nl/~jhh/jason.ht ml