1 / 15

Java Card Introduction

Java Card Introduction. Pieter Hartel. (Read: Z. Chen, Java Card Technology for Smart Cards, Ch 3&9, Addison Wesley, Reading, Massachusetts, 2000). Overview. Java Java Card. Java. High-level OO language Designed for mobility Large footprint Good tools, APIs. Balance: Feb 3: $8.00

melba
Download Presentation

Java Card Introduction

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Java Card Introduction Pieter Hartel (Read: Z. Chen, Java Card Technology for Smart Cards, Ch 3&9, Addison Wesley, Reading, Massachusetts, 2000)

  2. Overview • Java • Java Card

  3. Java • High-level OO language • Designed for mobility • Large footprint • Good tools, APIs

  4. Balance: Feb 3: $8.00 Feb 4: $2.00 Feb 6: $7.00- What is Java Safety? • Definition: nothing bad will happen • Type safety • Memory safety • Java safety is limited

  5. What is Java Security? • Definition: controlled access to resources • Security policy • Security mechanisms • Trust requires auditing

  6. Parsing Type checking Code generation Class loading Byte code verification Execution How is Java implemented? Java program Byte code class file compiler interpreter

  7. Nothing here Arbitrary instructions here Java and JVM security differ Java: Point p = new Point (1,0); JVM: 0 new Point 3 dup 4 iconst_1 5 iconst_0 6 invokespecial Point(int,int)

  8. Supported Java Features Small primitive data types: bool, byte, short One-dimensional arrays Java packages, classes, interfaces, exceptions Java object-oriented features: inheritance, virtual methods, overloading, dynamic object creation, etc. The int keyword and 32-bit integer data type support are optional. Unsupported Java Features Large primitive data types: long, double, float Characters and strings Multidimensional arrays Dynamic class loading Security manager Garbage collection and finalization Threads Object serialization Object cloning Differences Java and Java card

  9. Class loading Byte code verification CAP file generation Digital signature Class loading Signature verification Execution How is Java Card implemented? Byte code class file ‘Byte codes’ Cap file converter installer

  10. Life cycle • JCRE never stops • APDU determines applet

  11. Features • Persistent and transient objects • Transactions • Applet firewall and controlled object sharing • Cryptography

  12. Architecture

  13. 4 public void process(APDU apdu){ 6 byte[] buffer = apdu.getBuffer(); 7 byte cla = buffer[ISO7816.OFFSET_CLA]; 8 byte ins = buffer[ISO7816.OFFSET_INS]; 12 short bytesLeft = (short) (buffer[ISO7816.OFFSET_LC] & 0x00FF); 13 if(bytesLeft < (short)55) ISOException.throwIt( ISO7816.SW_WRONG_LENGTH ); 15 short readCount = apdu.setIncomingAndReceive(); 16 while(bytesLeft > 0){ 18 bytesLeft -= readCount; 19 readCount = apdu.receiveBytes (ISO7816.OFFSET_CDATA); 20 } 29 short le = apdu.setOutgoing(); 30 if(le < (short)2) ISOException.throwIt(ISO7816.SW_WRONG_LENGTH); 31 apdu.setOutgoingLength( (short)3 ); 34 buffer[0] = (byte)1; buffer[1] = (byte)2; buffer[3] = (byte)3; 35 apdu.sendBytes ( (short)0 , (short)3 ); 37 } apdu.cla(); throw new WrongLength(); 2 Do not alter the buffer! Process Method

  14. Applet firewall Context switch

  15. Conclusions • High-level • Smart card limitations visible • Widely supported

More Related