PasswordEncryption.java

/*
    Copyright (c) 2015 Wolfgang Imig
    
    This file is part of the library "JOA Issue Tracker for Microsoft Outlook".

    This file must be used according to the terms of   
      
      MIT License, http://opensource.org/licenses/MIT

 */
package com.wilutions.itol.db;

import java.io.UnsupportedEncodingException;

import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;

public class PasswordEncryption {

	private final static String IV = "happynewyearh201";
	private final static String encryptionKey = "18afc39c755144a9";

	public static String encrypt(String plainText) {
		try {
			byte[] data = plainText.getBytes("UTF-8");
			if (data.length % 16 != 0) {
				byte[] ndata = new byte[data.length + 16 - (data.length & 0x0F)];
				System.arraycopy(data, 0, ndata, 0, data.length);
				data = ndata;
			}
			Cipher cipher = Cipher.getInstance("AES/CBC/NoPadding", "SunJCE");
			SecretKeySpec key = new SecretKeySpec(encryptionKey.getBytes("UTF-8"), "AES");
			cipher.init(Cipher.ENCRYPT_MODE, key, new IvParameterSpec(IV.getBytes("UTF-8")));
			return bytesToString(cipher.doFinal(data));
		}
		catch (Throwable e) {
			throw new IllegalStateException(e);
		}
	}

	public static String decrypt(String cipherText) {
		try {
			Cipher cipher = Cipher.getInstance("AES/CBC/NoPadding", "SunJCE");
			SecretKeySpec key = new SecretKeySpec(encryptionKey.getBytes("UTF-8"), "AES");
			cipher.init(Cipher.DECRYPT_MODE, key, new IvParameterSpec(IV.getBytes("UTF-8")));
			return new String(cipher.doFinal(stringToBytes(cipherText)), "UTF-8").trim();
		}
		catch (Throwable e) {
			throw new IllegalStateException(e);
		}
	}

	private static byte[] stringToBytes(String s) throws UnsupportedEncodingException {
		// Previous version used
		// com.sun.org.apache.xml.internal.security.utils.Base64.
		// This class adds \n after each 76 chars, which disturbs the
		// java.util.Base64.
		StringBuilder sbuf = new StringBuilder(s.length());
		for (int i = 0; i < s.length(); i++) {
			char c = s.charAt(i);
			if (!Character.isWhitespace(c)) {
				sbuf.append(c);
			}
		}
		return java.util.Base64.getDecoder().decode(sbuf.toString());
	}

	private static String bytesToString(byte[] b) throws UnsupportedEncodingException {
		String s = java.util.Base64.getEncoder().encodeToString(b);
		// Add a \n after each 80 chars
		StringBuilder sbuf = new StringBuilder(s.length() + (s.length() / 76));
		int p = 0;
		while (p < s.length()) {
			int e = p + 76;
			if (e > s.length()) {
				e = s.length();
			}
			if (p != 0) {
				sbuf.append('\n');
			}
			sbuf.append(s.substring(p, e));
			p = e;
		}
		return sbuf.toString();
	}
}