Java AES 加密算法实现与模式详解

Java AES 加密算法实现与模式详解

import java.util.Arrays;  
import javax.crypto.Cipher;  
import javax.crypto.KeyGenerator;
import javax.crypto.SecretKey;  
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;

import org.apache.shiro.codec.Hex;  

/** 
 * AES 算法 对称加密，密码学中的高级加密标准 2005 年成为有效标准  
 */  
public class AES {  
    static Cipher cipher;  
    static final String KEY_ALGORITHM = "AES";  
    static final String CIPHER_ALGORITHM_ECB = "AES/ECB/PKCS5Padding";  
    /* 
     *  
     */  
    static final String CIPHER_ALGORITHM_CBC = "AES/CBC/PKCS5Padding";  
    /*  
     * AES/CBC/NoPadding 要求 
     * 密钥必须是 16 位的；Initialization vector (IV) 必须是 16 位 
     * 待加密内容的长度必须是 16 的倍数，如果不是 16 的倍数，就会出如下异常： 
     * javax.crypto.IllegalBlockSizeException: Input length not multiple of 16 bytes 
     *  
     *  由于固定了位数，所以对于被加密数据有中文的，加、解密不完整 
     *   
     *  可 以看到，在原始数据长度为 16 的整数 n 倍时，假如原始数据长度等于 16*n，则使用 NoPadding 时加密后数据长度等于 16*n， 
     *  其它情况下加密数据长 度等于 16*(n+1)。在不足 16 的整数倍的情况下，假如原始数据长度等于 16*n+m[其中 m 小于 16]， 
     *  除了 NoPadding 填充之外的任何方 式，加密数据长度都等于 16*(n+1). 
     */  
    static final String CIPHER_ALGORITHM_CBC_NoPadding = ;   
          
     SecretKey secretKey;  
            
         Exception {  
        
    }  
        
      
        Exception {  
        cipher = Cipher.getInstance(KEY_ALGORITHM);  
        
        secretKey = KeyGenerator.getInstance(KEY_ALGORITHM).generateKey();  
        System.out.println( + secretKey.getEncoded());  
        [] keyBytes = secretKey.getEncoded();
        
        
        
        secretKey =  (keyBytes, KEY_ALGORITHM);
        cipher.init(Cipher.ENCRYPT_MODE, secretKey);
        [] encrypt = cipher.doFinal(str.getBytes()); 
        System.out.println( + Arrays.toString(encrypt));  
        
        
        secretKey =  (keyBytes, KEY_ALGORITHM);
        cipher.init(Cipher.DECRYPT_MODE, secretKey);
        [] decrypt = cipher.doFinal(encrypt);  
        System.out.println( +  (decrypt));  
          
    }  
    
    
         Exception {
	
	   Cipher.getInstance();
	   KeyGenerator.getInstance().generateKey();
	[] keyBytes = serverSecretKey.getEncoded();
	   Hex.encodeToString(keyBytes);
	System.out.println(+keyStr);
	
	
	    (Hex.decode(keyStr), );
	   Cipher.getInstance();
	clientCiper.init(Cipher.ENCRYPT_MODE, clientSecretKey);
	   Hex.encodeToString(clientCiper.doFinal(content.getBytes()));
	System.out.println(+encryptStr);
	
	
	serverCiper.init(Cipher.DECRYPT_MODE, serverSecretKey);
	[] decodeBytes = serverCiper.doFinal(Hex.decode(encryptStr));
        System.out.println(+ (decodeBytes));
	
    }
      
      
        Exception {  
        cipher = Cipher.getInstance(CIPHER_ALGORITHM_ECB);  
        
        secretKey = KeyGenerator.getInstance(KEY_ALGORITHM).generateKey();  
        System.out.println( + secretKey.getEncoded().length);  
          
        cipher.init(Cipher.ENCRYPT_MODE, secretKey);
        [] encrypt = cipher.doFinal(str.getBytes()); 
          
        System.out.println( + Arrays.toString(encrypt));  
        cipher.init(Cipher.DECRYPT_MODE, secretKey);
        [] decrypt = cipher.doFinal(encrypt);  
        System.out.println( +  (decrypt));  
          
    }  
      
     [] getIV() {  
           ; 
         iv.getBytes();  
    }  
      
      
        Exception {  
        cipher = Cipher.getInstance(CIPHER_ALGORITHM_CBC);  
        
        secretKey = KeyGenerator.getInstance(KEY_ALGORITHM).generateKey();  
        System.out.println( + secretKey.getEncoded().length);  
          
        cipher.init(Cipher.ENCRYPT_MODE, secretKey,  (getIV()));
        [] encrypt = cipher.doFinal(str.getBytes()); 
          
        System.out.println( + Arrays.toString(encrypt));  
        cipher.init(Cipher.DECRYPT_MODE, secretKey,  (getIV()));
        [] decrypt = cipher.doFinal(encrypt);  
        System.out.println( +  (decrypt));  
          
    }  
      
      
        Exception {  
        cipher = Cipher.getInstance(CIPHER_ALGORITHM_CBC_NoPadding);  
        
        secretKey = KeyGenerator.getInstance(KEY_ALGORITHM).generateKey();  
        System.out.println( + secretKey.getEncoded().length);  
          
        cipher.init(Cipher.ENCRYPT_MODE, secretKey,  (getIV()));
        [] encrypt = cipher.doFinal(str.getBytes(), , str.length()); 
          
        System.out.println( + Arrays.toString(encrypt));  
        cipher.init(Cipher.DECRYPT_MODE, secretKey,  (getIV()));
        [] decrypt = cipher.doFinal(encrypt);  
          
        System.out.println( +  (decrypt));  
          
    }  
      
}