TrippleDES没有基地64编码：鉴于最后一块没有正确填充

Question

我想加密和解密一个字符串使用TrippleDES algorythm，而不使用Base64编码（我的应用程序将与另一个具有这些要求的应用程序交谈）。当我测试使用Base64编码/解码的东西时，一切都运行良好，但是当我转换为纯文本样式（就像我打电话的应用程序所要求的那样）时，一切都破裂了。

我读过这篇文章Given final block not properly padded它说，关键是错误的解码，但这是不可能的，因为这些线路实际上是在同一个变量传递密钥和改造两种：

ecipher = Cipher.getInstance(transformation); 
dcipher = Cipher.getInstance(transformation); 
ecipher.init(Cipher.ENCRYPT_MODE, key, iv); 
dcipher.init(Cipher.DECRYPT_MODE, key, iv); 

另外，我打印出来的编码字符串和数组两者的长度，它们的长度是8

我的输出，我得到的倍数：

originalText: Abcdefgh 
number of bites: 16 
cryptText: d4167d9e2b3b1b2d1f940bc45099da0a 
cryptText.length: 32 
cryptText.getBytes().length: 32 
Exception in thread "main" javax.crypto.BadPaddingException: Given final block not properly padded 
    at com.sun.crypto.provider.SunJCE_f.b(DashoA13*..) 
    at com.sun.crypto.provider.SunJCE_f.b(DashoA13*..) 
    at com.sun.crypto.provider.DESedeCipher.engineDoFinal(DashoA13*..) 
    at javax.crypto.Cipher.doFinal(DashoA13*..) 
Java Result: 1 

我完整的代码（本教程http://eternusuk.blogspot.com/2008/09/java-triple-des-example.html的稍作修改的版本）：

package com.test.encrypt; 

import javax.crypto.Cipher; 
import javax.crypto.SecretKey; 
import javax.crypto.SecretKeyFactory; 
import javax.crypto.spec.DESedeKeySpec; 
import javax.crypto.spec.IvParameterSpec; 
import org.apache.commons.codec.binary.Hex; 

public class TrippleDESTest 
{ 
    private Cipher ecipher; 
    private Cipher dcipher; 
    private String algorithm = "DESede"; 
    private String transformation = "DESede/CBC/PKCS5Padding"; 
    private String keyPhrase = "123456789"; //your keyphrase 24 bit 
    private SecretKey key; 
    private IvParameterSpec iv; 
    private static TrippleDESTest cryptoUtil; 
    private String ENCODING = "UTF-8"; 

    public static TrippleDESTest getInstance() throws Exception 
    { 
     if (cryptoUtil == null) 
     { 
      cryptoUtil = new TrippleDESTest(); 
     } 

     return cryptoUtil; 
    } 

    private TrippleDESTest() throws Exception 
    { 
      DESedeKeySpec keySpec = new DESedeKeySpec(keyPhrase.getBytes()); 
      key = SecretKeyFactory.getInstance(algorithm).generateSecret(keySpec); 
      iv = new IvParameterSpec(new byte[8]); 
      ecipher = Cipher.getInstance(transformation); 
      dcipher = Cipher.getInstance(transformation); 
      ecipher.init(Cipher.ENCRYPT_MODE, key, iv); 
      dcipher.init(Cipher.DECRYPT_MODE, key, iv); 
    } 

    public String encrypt(String str) throws Exception 
    { 
      byte[] utf8 = str.getBytes(ENCODING);  
      byte[] enc = ecipher.doFinal(utf8);     
      System.out.println("number of bites: " + enc.length);  
      return Hex.encodeHexString(enc); 
    } 

    public String decrypt(String str) throws Exception 
    { 
      byte[] dec = str.getBytes(); 
      byte[] utf8 = dcipher.doFinal(dec);  
      return Hex.encodeHexString(utf8); 
    } 

    public static void main(String[] args) throws Exception 
    { 
     TrippleDESTest test = TrippleDESTest.getInstance();   
     String originalText = "Abcdefgh";   
     System.out.println("originalText: " + originalText);   
     String cryptText = test.encrypt(originalText);   
     System.out.println("cryptText: " + cryptText);   
     System.out.println("cryptText.length: " + cryptText.length()); 
     System.out.println("cryptText.getBytes().length: " + cryptText.getBytes().length);   
     System.out.println("decote text: " + test.decrypt(cryptText)); 

    } 
}// end class TrippleDESTest 

提前感谢！

Answer 1

您正在以错误的顺序执行十六进制编码。您需要解密密文，而不是在您的decrypt方法中编码纯文本。