juddi-examples/more-uddi-samples/src/main/java/org/apache/juddi/samples/AES.java

/*
 * Copyright 2001-2013 The Apache Software Foundation.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 */
package org.apache.juddi.samples;

import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;
import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;

/**
 * This call is a simple test class that shows how to encrypt stuff in Java
 * using AES
 *
 * @author <a href="mailto:alexoree@apache.org">Alex O'Ree</a>
 */
public class AES {

        public static String GEN(int keysize) {
                KeyGenerator kgen;
                try {
                        kgen = KeyGenerator.getInstance("AES");
                        kgen.init(keysize);
                        SecretKey skey = kgen.generateKey();
                        byte[] raw = skey.getEncoded();
                        return asHex(raw);
                } catch (Exception ex) {
                }
                return null;
        }

        private static String asHex(byte buf[]) {
                //return new String(buf);
                StringBuilder strbuf = new StringBuilder(buf.length * 2);
                int i;

                for (i = 0; i < buf.length; i++) {
                        if (((int) buf[i] & 0xff) < 0x10) {
                                strbuf.append("0");
                        }
                        strbuf.append(Long.toString((int) buf[i] & 0xff, 16));
                }

                return strbuf.toString();
        }

        private static byte[] hexToBytes(String s) {
                //return s.getBytes();
                return hexToBytes(s.toCharArray());
        }
        private static final char[] kDigits = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a',
                'b', 'c', 'd', 'e', 'f'};

        private static byte[] hexToBytes(char[] hex) {
                int length = hex.length / 2;
                byte[] raw = new byte[length];
                for (int i = 0; i < length; i++) {
                        int high = Character.digit(hex[i * 2], 16);
                        int low = Character.digit(hex[i * 2 + 1], 16);
                        int value = (high << 4) | low;
                        if (value > 127) {
                                value -= 256;
                        }
                        raw[i] = (byte) value;
                }
                return raw;
        }
        //default key
        // private final static String something2 = "dde284c781d60ca0b56c4b23eec85217951dc99869402abd42c7dcc9080d60aa";

        public static void main(String[] args) throws Exception {
                //ee4bd3eefe38c3d996a89589de5b9698
                String key = GEN(128);
                System.out.println(key);

                byte[] raw = hexToBytes(key); //
                SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES");
                // Instantiate the cipher
                Cipher cipher = Cipher.getInstance("AES");
                cipher.init(Cipher.ENCRYPT_MODE, skeySpec);
                byte[] encrypted = cipher.doFinal("password".getBytes("UTF-8"));
                String enc = (asHex(encrypted));
                System.out.println(enc);

                skeySpec = new SecretKeySpec(hexToBytes(key), "AES");
                cipher.init(Cipher.DECRYPT_MODE, skeySpec);
                byte[] original = cipher.doFinal(hexToBytes(enc));

                System.out.println(new String(original, "UTF-8"));

        }
}