1. JCA, Cryptography for Java Programmer Shawn Shuang Zhang CS 627

2. Cryptography Users Application Integration Cryptographer End User Programmer Development PGP, SSL ? Math, SPI

3. JCA Figure 1-1. [1] Page 30 Figure 3-1

4. JCE Java Cryptography Extension

5. Providers Cipher API Cipher SPI

6. Restrictions ProviderFree?U.S. only? SunJCE 1.2.1YesNo SunJCE 1.2Yes CryptixYesNo IAIKNoNO

7. SunJCE RSA DES Triple DES MD5 SHA-1 Hmac with MD5 Hamc with SHA-1

8. Cryptix LIKI91 Triple DES DES2X DESX IDEA RC2 RC4 Blowfish CAST5 SPEED SQUARE

9. IAIK-ICE RSA Triple DES IDEA RC2 RC4 MD2 MD5 SHA-1 Hmac with MD5 Hmac with SHA-1 CAST5 GOST

10. Example Get a Cipher –Public static Cipher getInstance(String algorithm, String provider) throws NoSuchAlgorithmException –Cipher cipher=Cipher.getInstance(“DEC”)

11. Initialize a Cipher ENCRYPT_MODE DECRYPT_MODE –Public final void init(int opmode, Key key, AlgorithmParameterSpec params, SecureRandom random) throws InvalidAlgorithmParameterException –Cipher.init(Cipher.ENCRYPT_MODE, Key);

12. Feed the data Public final byte[] update(byte[] input) throws IllegalStateException –Byte[] ciphertext=cipher.update(plaintext)

13. doFinal Public final byte[] doFinal() IllegalStateException, IllegalBlockSizeException, BadpaddingExceptioin –Byte[] ciphertext=cipher.doFinal();

14. Example Cipher cipher=Cipher.getInstance(“DES/CBC/PKCS5Padding”); cipher.init(Cipher.ENCRYPT_MODE, key); Byte[] palintext=“plain”.getBytes(); Byte[] step=cipher.update(plaintext); Byte[] ciphertext=cipher.doFinal(plaintext);

15. References Java Cryptography by Jonathan Knudsen Internet Cryptography by Richard E. Smith http://java.sun.com/products/jsk/1.4/jce http://www.systemics.com/software/cryptix- javahttp://www.systemics.com/software/cryptix- java http://wwwjce.iaik.tu-graz.ac.at/