JceSunDesPaddingTest.java - JCE DES Padding Test

This section provides a tutorial example to test the PKCS5Padding schema used by the DES implementation in the JDK JCE package.

Let's modify the above testing program to see how PKCS5Padding schema works.

/**
 * JceSunDesPaddingTest.java
#- Copyright (c) 2013, HerongYang.com, All Rights Reserved.
 */
import java.security.spec.*;
import javax.crypto.*;
import javax.crypto.spec.*;
class JceSunDesPaddingTest {
   public static void main(String[] a) {
      if (a.length<2) {
         System.out.println("Usage:");
         System.out.println("java JceSunDesPaddingTest 1/2/3"
            + " algorithm");
         return;
      }
      String test = a[0];
      String algorithm = a[1];
      try {
         byte[] theKey = null;
         byte[] theMsg = null; 
         byte[] theExp = null; 
         if (test.equals("1")) { 
            theKey = hexToBytes("133457799BBCDFF1");
            theMsg = hexToBytes("0123456789ABCDEF");
            theExp = hexToBytes("85E813540F0AB405");
         } else if (test.equals("2")) { 
            theKey = hexToBytes("38627974656B6579"); // "8bytekey"
            theMsg = hexToBytes("6D6573736167652E"); // "message."
            theExp = hexToBytes("7CF45E129445D451");
         } else if (test.equals("3")) { 
            theKey = hexToBytes("133457799BBCDFF1"); // = test 1
            theMsg = hexToBytes("0808080808080808"); // PKCS5Padding
            theExp = hexToBytes("FDF2E174492922F8");
         } else {
            System.out.println("Wrong option. For help enter:");
            System.out.println("java JceSunDesPaddingTest");
            return;
         }	
         KeySpec ks = new DESKeySpec(theKey);
         SecretKeyFactory kf 
            = SecretKeyFactory.getInstance("DES");
         SecretKey ky = kf.generateSecret(ks);
         Cipher cf = Cipher.getInstance(algorithm);
         cf.init(Cipher.ENCRYPT_MODE,ky);
         byte[] theCph = cf.doFinal(theMsg);
         System.out.println("Key     : "+bytesToHex(theKey));
         System.out.println("Message : "+bytesToHex(theMsg));
         System.out.println("Cipher  : "+bytesToHex(theCph));
         System.out.println("Expected: "+bytesToHex(theExp));
      } catch (Exception e) {
         e.printStackTrace();
         return;
      }
   }
   public static byte[] hexToBytes(String str) {
      if (str==null) {
         return null;
      } else if (str.length() < 2) {
         return null;
      } else {
         int len = str.length() / 2;
         byte[] buffer = new byte[len];
         for (int i=0; i<len; i++) {
             buffer[i] = (byte) Integer.parseInt(
                str.substring(i*2,i*2+2),16);
         }
         return buffer;
      }

   }
   public static String bytesToHex(byte[] data) {
      if (data==null) {
         return null;
      } else {
         int len = data.length;
         String str = "";
         for (int i=0; i<len; i++) {
            if ((data[i]&0xFF)<16) str = str + "0" 
               + java.lang.Integer.toHexString(data[i]&0xFF);
            else str = str
               + java.lang.Integer.toHexString(data[i]&0xFF);
         }
         return str.toUpperCase();
      }
   }            
}

Let's run this program with different options:

java JceSunDesPaddingTest 1 DES/ECB/NoPadding

Key     : 133457799BBCDFF1
Message : 0123456789ABCDEF
Cipher  : 85E813540F0AB405
Expected: 85E813540F0AB405

java JceSunDesPaddingTest 1 DES/ECB/PKCS5Padding

Key     : 133457799BBCDFF1
Message : 0123456789ABCDEF
Cipher  : 85E813540F0AB405FDF2E174492922F8
Expected: 85E813540F0AB405

java JceSunDesPaddingTest 1 DES

Key     : 133457799BBCDFF1
Message : 0123456789ABCDEF
Cipher  : 85E813540F0AB405FDF2E174492922F8
Expected: 85E813540F0AB405

java JceSunDesPaddingTest 3 DES/ECB/PKCS5Padding

Key     : 133457799BBCDFF1
Message : 0808080808080808
Cipher  : FDF2E174492922F8FDF2E174492922F8
Expected: FDF2E174492922F8

The results tells us that:

Table of Contents

 About This Book

 Cryptography Terminology

 Cryptography Basic Concepts

 Introduction to AES (Advanced Encryption Standard)

 Introduction to DES Algorithm

 DES Algorithm - Illustrated with Java Programs

 DES Algorithm Java Implementation

DES Algorithm - Java Implementation in JDK JCE

 DES Java Implementation in JDK by Sun

 Steps of Using DES Algorithm in JDK JCE

 Testing DES Algorithm in JDK JCE

 What Is PKCS5Padding?

JceSunDesPaddingTest.java - JCE DES Padding Test

 DES Encryption Operation Modes

 DES in Stream Cipher Modes

 PHP Implementation of DES - mcrypt

 Blowfish - 8-Byte Block Cipher

 Secret Key Generation and Management

 Cipher - Secret Key Encryption and Decryption

 Introduction of RSA Algorithm

 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

 MD5 Mesasge Digest Algorithm

 SHA1 Mesasge Digest Algorithm

 OpenSSL Introduction and Installation

 OpenSSL Generating and Managing RSA Keys

 OpenSSL Managing Certificates

 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"

 Using Certificates in IE (Internet Explorer)

 Using Certificates in Firefox

 Using Certificates in Google Chrome

 Outdated Tutorials

 References

 PDF Printing Version