**Cryptography Tutorials - Herong's Tutorial Examples** - Version 5.40, by Dr. Herong Yang

DES Operation Modes in JCE

This section describes what DES operation modes are implemented in the JDK JCE package, and how to use them.

Sun has implemented all 4 operation modes described above in their JDK JCE (Java Cryptography Extension) package. To use DES operation modes properly, you need to:

1. Specify the operation mode name as part of the algorithm name when calling Cipher.getInstance(algorithm) to create a cipher object like:

Cipher cObj1 = Cipher.getInstance("DES/ECB/NoPadding"); Cipher cObj2 = Cipher.getInstance("DES/CBC/NoPadding"); Cipher cObj3 = Cipher.getInstance("DES/CFB/NoPadding"); Cipher cObj4 = Cipher.getInstance("DES/OFB/NoPadding");

2. Initialize the cipher object with the key and the IV (Initial Vector) by using the IvParameterSpec class like:

AlgorithmParameterSpec apsObj = new IvParameterSpec(theIV); cObj.init(Cipher.ENCRYPT_MODE, keyObj, apsObj);

Table of Contents

Introduction to AES (Advanced Encryption Standard)

DES Algorithm - Illustrated with Java Programs

DES Algorithm Java Implementation

DES Algorithm - Java Implementation in JDK JCE

►DES Encryption Operation Modes

DES Encryption Operation Mode Introduction

What is ECB (Electronic CodeBook) Operation Mode?

What is CBC (Cipher Block Chaining) Operation Mode?

What is CFB (Cipher FeedBack) Operation Mode?

What is OFB (Output FeedBack) Operation Mode?

JCE DES Operation Mode Testing Program

JCE DES Operation Mode Testing Program Result

PHP Implementation of DES - mcrypt

Blowfish - 8-Byte Block Cipher

Secret Key Generation and Management

Cipher - Secret Key Encryption and Decryption

RSA Implementation using java.math.BigInteger Class

Introduction of DSA (Digital Signature Algorithm)

Java Default Implementation of DSA

Private key and Public Key Pair Generation

PKCS#8/X.509 Private/Public Encoding Standards

Cipher - Public Key Encryption and Decryption

OpenSSL Introduction and Installation

OpenSSL Generating and Managing RSA Keys

OpenSSL Generating and Signing CSR

OpenSSL Validating Certificate Path

"keytool" and "keystore" from JDK

"OpenSSL" Signing CSR Generated by "keytool"

Migrating Keys from "keystore" to "OpenSSL" Key Files

Certificate X.509 Standard and DER/PEM Formats

Migrating Keys from "OpenSSL" Key Files to "keystore"