Smart Cards A smart card is a plastic

Smart Cards § A smart card is a plastic card that contains an embedded integrated circuit (IC). § They store and process Information. § Smart Cards Can be used to add authentication and secure access to information systems that require a high level of security Sara Javanmardi, INF 123 - Software Architectures, Distributed Systems and Interoperability 1

Properties of Smart Cards § Highly secure-Tempering with one, results in destruction of the information it contains § Don’t contain battery- Become active when connected with a card reader § Come in two forms Contact or Contact less Sara Javanmardi, INF 123 - Software Architectures, Distributed Systems and Interoperability 2

What is a Java Card? § Adoption of Java Platform for usage on Smart Cards. Sara Javanmardi, INF 123 - Software Architectures, Distributed Systems and Interoperability 3

Java Card Features • Receives clock and power from terminal • Three types of memory: – Random Access Memory (RAM) – Read-Only Memory (ROM) – Erasable Read-Only Memory (EEPROM) • Restricted Resources – – Slow and simple microprocessor (8 -bit) RAM ~1 Kb ROM ~64 Kb EEPROM ~16 -64 Kb • Restricted Version of Java Sara Javanmardi, INF 123 - Software Architectures, Distributed Systems and Interoperability 4

Java Card/Terminal System APDU = Application Protocol Data Unit Sara Javanmardi, INF 123 - Software Architectures, Distributed Systems and Interoperability 5

The Card-Side q Elements: § One or more Java Applets § Card’s operating System § Java Card Runtime Environment(JCRE) • Java Card Virtual Machine • Java Card Framework and APIs Sara Javanmardi, INF 123 - Software Architectures, Distributed Systems and Interoperability 6

The Message-Passing Model Sara Javanmardi, INF 123 - Software Architectures, Distributed Systems and Interoperability 7

Java for Java Cards Features Supported • Small primitive data types: boolean, byte, short. • One dimensional arrays. • Object oriented features: inheritance, virtual methods, dynamic object creation, overloading, scope. Not Supported • Large primitive data types: long, double, float. • Characters, strings. • Multidimensional arrays. • Dynamic class loading. • Garbage collection. • Threads. • Object Cloning. Sara Javanmardi, INF 123 - Software Architectures, Distributed Systems and Interoperability 8

Developing a Java Card Applet 1. Write the Java source. 2. Compile your source. 3. Convert the class files into a Converted Applet (CAP) file (binary representation of classes and interfaces). 4. Verify that the CAP is valid (structure, valid bytecode subset, inter-package dependencies). 5. Install the CAP file. Sara Javanmardi, INF 123 - Software Architectures, Distributed Systems and Interoperability 9

Message-Passing Model Sara Javanmardi, INF 123 - Software Architectures, Distributed Systems and Interoperability 10

APDU Structure • • • CLA, INS define the command P 1, P 2 – parameters Lc – data field length Le – maximum response length SW 1, SW 2 – response status Sara Javanmardi, INF 123 - Software Architectures, Distributed Systems and Interoperability 11

A Challenge in Java Card Programming • Java Cards have very restricted resources – Limited Memory – Limited Computing Power • Can we use terminal’s resources to overcome the restriction provided that the terminal is potentially untrusted? Sara Javanmardi, INF 123 - Software Architectures, Distributed Systems and Interoperability 12

Authentication • Registration Phase • Login Phase • Verification Phase Sara Javanmardi, INF 123 - Software Architectures, Distributed Systems and Interoperability 13

Registration Phase • User Ui submits his identity IDi and password PWi to a server for registration via secure channel. If the server accepts the request, it computes: • The server issues Ui a smart card containing: – Ri – h( ), where h( ) is a one-way hash function • x is the secret key maintained by the server Sara Javanmardi, INF 123 - Software Architectures, Distributed Systems and Interoperability 14

Login Phase • When Ui wants to login to the server, he inserts his smart card into a terminal then, the smart card performs the following steps: Sara Javanmardi, INF 123 - Software Architectures, Distributed Systems and Interoperability 15

Verification Phase – Server side • After receiving the message (IDi, T, C 2) from Ui, the server performs the following steps to authenticate Ui: Sara Javanmardi, INF 123 - Software Architectures, Distributed Systems and Interoperability 16

Verification Phase – Client side • After receiving the message (C 3, T’’) from the server, Ui performs the following steps to authenticate the server: Sara Javanmardi, INF 123 - Software Architectures, Distributed Systems and Interoperability 17

Sample Scenario - Login Sara Javanmardi, INF 123 - Software Architectures, Distributed Systems and Interoperability 18

Sample Scenario - Verify Sara Javanmardi, INF 123 - Software Architectures, Distributed Systems and Interoperability 19