Test program to detect the need for "Unlimited Strength Policy Files"

TestPolicyFiles.java

import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;
import javax.crypto.SecretKey;
 
public class TestPolicyFiles {
 
    public static void main(String[] args) {
        try {
            KeyGenerator keygen = KeyGenerator.getInstance("AES");
            keygen.init(256);
            SecretKey key = keygen.generateKey();
            Cipher aes = Cipher.getInstance("AES/CBC/PKCS5PAdding");
            aes.init(Cipher.ENCRYPT_MODE, key);
        } catch (Exception ex) {
            throw new RuntimeException(ex);
        }
    }
}

Throws "java.security.InvalidKeyException: Illegal key size or default parameters" if policy files are needed, otherwise it runs through. OpenJDK doesn't need the policy files at all. See http://www.eyrie.org/~eagle/notes/debian/jce-policy.html for more details.

Place this file in some directory. Then, to test whether your Java installation needs the policy files, execute:

javac TestPolicyFiles.java
java TestPolicyFiles

If you still need the policy files, there will be an exception, otherwise there will be a message indicating success.

@emboss ❤️