Generating serial or hex code for product licensing

问题

Is there way to generate serial/hex code something like: xxxx-xxxx-xxxx-xxxx-xxxx-xxxx using java api? when product decipher the code it should able to extract

Name
Validity
Mac Address
Additional information

Code will be generated based on above factors. I have tried to RSA/ECB/PKCS1Padding with private key/public key. and then converting to HEX, but it needs private key sixe of 4096 and hex code generated is too long!

public class ProductKeyGenerator {
private static final String transformation = "RSA/ECB/PKCS1Padding";

public static void main(String[] args) {
    String cleartext = "CN=CompanyName;mac=some mac;@host=somehost;email=admin@somedomain.com;issued=01/01/20013;expire=12/12/2013";
    ProductKeyGenerator pgen = new ProductKeyGenerator();
    String productKey = pgen.generate(cleartext);
    System.out.println(productKey);
}

   ...
   ...
   ...
String generate(String data) {
    //encrypted hex
    String hexEnc = null;
    try {
        //--sign
        String signature = sign(data);
        data += ";sign=" + signature;

        byte[] dataBytes = data.getBytes("utf-8");
        //encrypt
        byte[] encBytes = encrypt(dataBytes);
        hexEnc = Hex.encodeHexString(encBytes);
    } catch (Exception e) {
        e.printStackTrace();
    }
    return hexEnc;
}

String sign(String text) {
    String signed = null;
    try {
        Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());
        byte[] data = text.getBytes("utf-8");
        byte[] digitalSignature = signData(data);
        signed = Hex.encodeHexString(digitalSignature);
    } catch (Exception e) {
        e.printStackTrace();
    }
    return signed;
}
   ...
   ...
   ...

   }

回答1:

With custom data you can't create a serial number with fixed length. But you can associate a serial number with information e.g. in database. Simple serial number generator:

String serial = UUID.randomUUID().toString().toUpperCase();
System.out.println(serial);

PS: It's very unsafe to use mac address in serial number. It's very easy to change.

来源：https://stackoverflow.com/questions/18021045/generating-serial-or-hex-code-for-product-licensing

标签

java

security

encryption

code-access-security