AES暗号解読のJAVA実現【二】

使用環境JDK 1.8
この方法の鍵は16ビットでなくてもよく、オフセット量は16ビットである.

import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.security.InvalidAlgorithmParameterException;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import java.security.Security;

import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.KeyGenerator;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.SecretKey;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;

import org.bouncycastle.jce.provider.BouncyCastleProvider;

import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;

/**
 * AES   /  [  128        ]

 *       main  ，          iv key  

 *   ：  AES     ，      16 ，      16 ；   16 ，     ；

 *   ，           128        ，         ，        ，    。

 * 
 *
 */
public class AES {

	public static  String key = "ThisIsMyTestKey12345";
	public static  String iv  = "1234567890123456"; 

	/**
	 *      
	 * @return
	 * @throws UnsupportedEncodingException
	 */
	private static IvParameterSpec getIV() throws UnsupportedEncodingException {
		return new IvParameterSpec(iv.getBytes("UTF-8"));
	}

	/**
	 *     
	 * @return
	 * @throws UnsupportedEncodingException
	 * @throws NoSuchAlgorithmException
	 */
	public static SecretKeySpec getKey() throws UnsupportedEncodingException, NoSuchAlgorithmException {
		Security.addProvider(new BouncyCastleProvider());
		KeyGenerator kgen = KeyGenerator.getInstance("AES");
		kgen.init(128, new SecureRandom(key.getBytes()));
		SecretKey keygen = kgen.generateKey();
		SecretKeySpec keySpec = new SecretKeySpec(keygen.getEncoded(), "AES");
		return keySpec;
	}

	/**
	 *   
	 * 
	 * @param content
	 * @return
	 */
	public static String decrypt(String content) {
		try {

			Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
			cipher.init(Cipher.DECRYPT_MODE, getKey(), getIV());
			byte[] decodedContent    = new BASE64Decoder().decodeBuffer(content);
			byte[] original = cipher.doFinal(decodedContent);
			return new String(original);
		} catch (IOException e) {
			e.printStackTrace();
		}  catch (IllegalBlockSizeException e) {
			e.printStackTrace();
		} catch (BadPaddingException e) {
			e.printStackTrace();
		} catch (InvalidKeyException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (InvalidAlgorithmParameterException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (NoSuchAlgorithmException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (NoSuchPaddingException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		;

		return null;
	}

	/**
	 *   
	 * 
	 * @param content
	 * @return
	 */
	public static String encrypt(String content) {

		try {
			Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
			cipher.init(Cipher.ENCRYPT_MODE, getKey(), getIV());
			byte[] contentByte = content.getBytes("UTF-8");
			byte[] result = cipher.doFinal(contentByte);
			return new BASE64Encoder().encode(result);
		} catch (IllegalBlockSizeException e) {
			e.printStackTrace();
		} catch (BadPaddingException e) {
			e.printStackTrace();
		} catch (InvalidKeyException e) {
 			e.printStackTrace();
		} catch (InvalidAlgorithmParameterException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (UnsupportedEncodingException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (NoSuchAlgorithmException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (NoSuchPaddingException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		};

		return null;
	}
 
	 
	/**
	 *         
	 * @param args
	 * @throws UnsupportedEncodingException
	 */
	public static void main(String[] args) throws UnsupportedEncodingException {
		String content = "     ，     ";
		AES.key +="ThisIsMyTestKey12345ThisIsMyTestKey12345ThisIsMyTestKey12345ThisIsMyTestKey12345ThisIsMyTestKey12345ThisIsMyTestKey12345";
		//   
		System.out.println("   ：" + content);
		String resultString = AES.encrypt(content);
		System.out.println("   ：" + resultString);
		//   
		String decryptResult = AES.decrypt(resultString);
		System.out.println("   ：" + decryptResult);

	}

}