com.xinferin.licensing.LicenceActivator.java Source code

Introduction

Here is the source code for com.xinferin.licensing.LicenceActivator.java

Source

/*
 *   XLicenser Source Code
 *   Copyright (C) 2015 XINFERIN Technologies 
 *  
 *    All Rights Reserved
 * 
 */

package com.xinferin.licensing;

import java.security.KeyFactory;
import java.security.NoSuchAlgorithmException;
import java.security.PublicKey;
import java.security.Signature;
import java.security.SignatureException;
import java.security.spec.EncodedKeySpec;
import java.security.spec.InvalidKeySpecException;
import java.security.spec.X509EncodedKeySpec;

import org.apache.commons.codec.binary.Base64;

public class LicenceActivator {

    private String spublicKey;
    private PublicKey publicKey;

    public LicenceActivator(String spublicKey) {
        this.spublicKey = spublicKey;
    }

    private void initialiseKeys() throws Exception {
        try {

            byte[] publicKeyBytes = Base64.decodeBase64(spublicKey);

            KeyFactory keyFactory = KeyFactory.getInstance("RSA");
            EncodedKeySpec publicKeySpec = new X509EncodedKeySpec(publicKeyBytes);
            publicKey = keyFactory.generatePublic(publicKeySpec);

        } catch (InvalidKeySpecException e) {
            throw new Exception("Invalid Key Specs not valid Key files." + e.getCause());
        } catch (NoSuchAlgorithmException e) {
            throw new Exception("There is no such algorithm. Please check the JDK ver." + e.getCause());
        }
    }

    /**
     * Verifies the signature for the given bytes using the public key.
     * @param signature Signature
     * @param data Data that was signed
     * @return boolean True if valid signature else false
     * @throws Exception 
    */
    public boolean verifySignature(byte[] signature, byte[] data) throws Exception {

        try {
            initialiseKeys();
            Signature signatureInstance = Signature.getInstance("SHA1withRSA");
            signatureInstance.initVerify(publicKey);
            signatureInstance.update(data);

            return signatureInstance.verify(signature);
        } catch (NoSuchAlgorithmException e) {
            throw new Exception("There is no such algorithm. Please check the JDK ver." + e.getCause());
        } catch (SignatureException e) {
            throw new Exception("There is a problem with the signature provided " + e.getCause());
        }
    }
}