Class CryptLib

Skay_Exp/src/tools/CryptLib.java:34–282

CrossPlatform CryptLib This cross platform CryptLib uses AES 256 for encryption. This library can be used for encryptoion and de-cryption of string on iOS, Android and Windows platform. Features: 1. 256 bit AES encryption 2. Random IV generation. 3. Provision for SHA256 hashing of ke

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public class CryptLib {

    /**
     * Encryption mode enumeration
     */
    private enum EncryptMode {
        ENCRYPT, DECRYPT;
    }

    // cipher to be used for encryption and decryption
    Cipher _cx;

    // encryption key and initialization vector
    byte[] _key, _iv;

    public CryptLib() throws NoSuchAlgorithmException, NoSuchPaddingException {
        // initialize the cipher with transformation AES/CBC/PKCS5Padding
        _cx = Cipher.getInstance("AES/CBC/PKCS5Padding");
        _key = new byte[32]; //256 bit key space
        _iv = new byte[16]; //128 bit IV
    }

    /**
     * Note: This function is no longer used.
     * This function generates md5 hash of the input string
     * @param inputString
     * @return md5 hash of the input string
     */
    public static final String md5(final String inputString) {
        final String MD5 = "MD5";
        try {
            // Create MD5 Hash
            MessageDigest digest = java.security.MessageDigest
                    .getInstance(MD5);
            digest.update(inputString.getBytes());
            byte messageDigest[] = digest.digest();

            // Create Hex String
            StringBuilder hexString = new StringBuilder();
            for (byte aMessageDigest : messageDigest) {
                String h = Integer.toHexString(0xFF & aMessageDigest);
                while (h.length() < 2)
                    h = "0" + h;
                hexString.append(h);
            }
            return hexString.toString();

        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
        }
        return "";
    }

    /**
     *
     * @param _inputText
     *            Text to be encrypted or decrypted
     * @param _encryptionKey