java中的AES 256算法遇到 Illegal key size or default para

報錯堆棧以下：

 

Caused by: java.security.InvalidKeyException:Illegal key size or default parameters
    at javax.crypto.Cipher.a(DashoA13*..)~[na:1.6]    at javax.crypto.Cipher.a(DashoA13*..)~[na:1.6]    at javax.crypto.Cipher.a(DashoA13*..)~[na:1.6]    at javax.crypto.Cipher.init(DashoA13*..)~[na:1.6]    at javax.crypto.Cipher.init(DashoA13*..)~[na:1.6]    at my.package.Something.decode(RC4Decoder.java:25)~[my.package.jar:na]

 

 

Google到問題緣由，連接地址以下：

http://stackoverflow.com/questions/6481627/java-security-illegal-key-size-or-default-parameters

根據回答找到下載新jar包連接地址以下：

http://www.oracle.com/technetwork/java/javase/downloads/jce-6-download-429243.html

把裏面的兩個jar包：local_policy.jar 和 US_export_policy.jar 替換掉原來安裝目錄C:\Program Files\Java\jre6\lib\security 下的兩個jar包接能夠了

而後就從新運行程序，不會報錯了，測試代碼以下：

 

1. public class Test {  

2.     public static void main(String[] args) throws Exception {  

3.          KeyGenerator keyGen = KeyGenerator.getInstance("AES");  

4.          keyGen.init(256);  

5.          SecretKey key = keyGen.generateKey();  

6.          ObjectOutputStream oop = new ObjectOutputStream(new  

7.          FileOutputStream("c:\\key.dat"));  

8.          oop.writeObject(key);  

9.          oop.close();  

10.           

11.         String strTest = "Hello, Jason";  

12.         byte[] strAfterAES = encryptData(strTest.getBytes());  

13.         System.out.println(new String(strAfterAES));  

14.         byte[] strOriContent = decryptData(strAfterAES);  

15.         System.out.println(new String(strOriContent));  

16.     }  

17.   

18.   

19.     public static byte[] encryptData(byte[] input) throws Exception {  

20.         ObjectInputStream in = new ObjectInputStream(new FileInputStream("c:\\key.dat"));  

21.         SecretKey aeskey = (SecretKey) in.readObject();  

22.         Cipher c1 = Cipher.getInstance("AES");  

23.         c1.init(Cipher.ENCRYPT_MODE, aeskey);  

24.         byte[] cipherByte = c1.doFinal(input);  

25.         return cipherByte;  

26.     }  

27.   

28.   

29.     public static byte[] decryptData(byte[] input) throws Exception {  

30.         ObjectInputStream in = new ObjectInputStream(new FileInputStream("c:\\key.dat"));  

31.         SecretKey aeskey = (SecretKey) in.readObject();  

32.         Cipher c1 = Cipher.getInstance("AES");  

33.         c1.init(Cipher.DECRYPT_MODE, aeskey);  

34.         byte[] clearByte = c1.doFinal(input);  

35.         return clearByte;  

36.     }  

37. }  

 

BTW:

 If ur JVM is IBM JVM pls refer to the below link to update the unlimited key size jars

http://pic.dhe.ibm.com/infocenter/wasinfo/v7r0/index.jsp?topic=%2Fcom.ibm.websphere.nd.multiplatform.doc%2Finfo%2Fae%2Fae%2Ftwbs_tunev6wss.html