Checking if Unlimited Cryptography is available

Question

How can I check, in Java code, if the current JVM have unlimited strength cryptography available?

Answer 1

In the same spirit as the answer of Dan Cruz, but with a single line of code and without going trough exceptions:

boolean limit = Cipher.getMaxAllowedKeyLength("RC5")<256; 

So a complete program might be:

import javax.crypto.Cipher;  public class TestUCE {   public static void main(String args[]) throws Exception {     boolean unlimited =       Cipher.getMaxAllowedKeyLength("RC5") >= 256;     System.out.println("Unlimited cryptography enabled: " + unlimited);   } } 

Answer 2

If you are on Linux and you have installed the JDK (but Beanshell is not available), you can check with the runscript command provided with the JDK.

jrunscript -e 'exit (javax.crypto.Cipher.getMaxAllowedKeyLength("RC5") >= 256 ? 0 : 1);'; echo $? 

This returns a 0 status code if the Unlimited Cryptography is available, or 1 if not available. Zero is the correct 'success' return value for shell functions, and non-zero indicates a failure.