Invalid key size in Java symmetric encryption program

Question

This is my basic symmetric encryption program. As im learning now I want to know how this is working. And I have the following Exception:

Exception in thread "main" java.security.InvalidKeyException: Illegal key size or default parameters at javax.crypto.Cipher.a(DashoA13*..) at javax.crypto.Cipher.init(DashoA13*..) at javax.crypto.Cipher.init(DashoA13*..) at sample.MainClass.main(MainClass.java:24)

This is my program:

public class MainClass {
     public static void main(String[] args) throws Exception {
            Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());        
            byte[] input = " www.java2s.com ".getBytes();
            byte[] keyBytes = new byte[] { 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09,
                0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17 };


            SecretKeySpec key = new SecretKeySpec(keyBytes, "AES");
            Cipher cipher = Cipher.getInstance("AES/ECB/NoPadding", "BC");
            System.out.println("input text : " + new String(input));

            // encryption pass

            byte[] cipherText = new byte[input.length];
            cipher.init(Cipher.ENCRYPT_MODE, key);
            int ctLength = cipher.update(input, 0, input.length, cipherText, 0);
            ctLength += cipher.doFinal(cipherText, ctLength);
            System.out.println("cipher text: " + new String(cipherText) + " bytes: " + ctLength);

            // decryption pass

            byte[] plainText = new byte[ctLength];
            cipher.init(Cipher.DECRYPT_MODE, key);
            int ptLength = cipher.update(cipherText, 0, ctLength, plainText, 0);
            ptLength += cipher.doFinal(plainText, ptLength);
            System.out.println("plain text : " + new String(plainText) + " bytes: " + ptLength);
          }
}

Can you please tell me how to solve this problem?

possible duplicate of [Java Security: Illegal key size or default parameters?](http://stackoverflow.com/questions/6481627/java-security-illegal-key-size-or-default-parameters) — Duncan Jones, Jan 22 '13 at 15:08
If you are learning a new language, I would suggest you increase your appetite for researching your own answers. A simple Google of your exception message brings up hundreds of pages that explain the same solution (thanks @owlstead). This is a great starting point for any exceptions you don't understand in Java. — Duncan Jones, Jan 22 '13 at 15:10
Also possible duplicate of https://stackoverflow.com/questions/19503926/java-security-aes-encryption-key-length — Forbin, Oct 21 '19 at 14:54

score 1 · Answer 1 · edited May 23 '17 at 12:18

This does indeed seem like a duplicate of Java Security: Illegal key size or default parameters? . You probably need to replace your local_policy.jar and US_export_policy.jar with the Unlimited Security versions. You can download them here: http://www.oracle.com/technetwork/java/javase/downloads/jce-6-download-429243.html

These files should be in your jre/lib/security/ folder. Also, for me I had a ton of different JREs in different locations, and the one I was using was inside my jdk folder path. It took me the longest time to figure this crap out

Invalid key size in Java symmetric encryption program

1 Answers1