/**
 * Password based encryption using AES - CBC 256 bits.
 */
@Override
public EncryptedData encrypt(byte[] plainBytes, KeyParameter aesKey) throws KeyCrypterException {
    checkNotNull(plainBytes);
    checkNotNull(aesKey);

    try {
        // Generate iv - each encryption call has a different iv.
        byte[] iv = new byte[BLOCK_LENGTH];
        secureRandom.nextBytes(iv);

        ParametersWithIV keyWithIv = new ParametersWithIV(aesKey, iv);

        // Encrypt using AES.
        BufferedBlockCipher cipher = new PaddedBufferedBlockCipher(new CBCBlockCipher(new AESFastEngine()));
        cipher.init(true, keyWithIv);
        byte[] encryptedBytes = new byte[cipher.getOutputSize(plainBytes.length)];
        final int length1 = cipher.processBytes(plainBytes, 0, plainBytes.length, encryptedBytes, 0);
        final int length2 = cipher.doFinal(encryptedBytes, length1);

        return new EncryptedData(iv, Arrays.copyOf(encryptedBytes, length1 + length2));
    } catch (Exception e) {
        throw new KeyCrypterException("Could not encrypt bytes.", e);
    }
}
 

/**
 * Decrypt bytes previously encrypted with this class.
 *
 * @param dataToDecrypt The data to decrypt
 * @param aesKey        The AES key to use for decryption
 * @return The decrypted bytes
 * @throws KeyCrypterException if bytes could not be decrypted
 */
@Override
public byte[] decrypt(EncryptedData dataToDecrypt, KeyParameter aesKey) throws KeyCrypterException {
    checkNotNull(dataToDecrypt);
    checkNotNull(aesKey);

    try {
        ParametersWithIV keyWithIv = new ParametersWithIV(new KeyParameter(aesKey.getKey()), dataToDecrypt.initialisationVector);

        // Decrypt the message.
        BufferedBlockCipher cipher = new PaddedBufferedBlockCipher(new CBCBlockCipher(new AESFastEngine()));
        cipher.init(false, keyWithIv);

        byte[] cipherBytes = dataToDecrypt.encryptedBytes;
        byte[] decryptedBytes = new byte[cipher.getOutputSize(cipherBytes.length)];
        final int length1 = cipher.processBytes(cipherBytes, 0, cipherBytes.length, decryptedBytes, 0);
        final int length2 = cipher.doFinal(decryptedBytes, length1);

        return Arrays.copyOf(decryptedBytes, length1 + length2);
    } catch (Exception e) {
        throw new KeyCrypterException("Could not decrypt bytes", e);
    }
}
 

/**
 * Password based encryption using AES - CBC 256 bits.
 */
@Override
public EncryptedData encrypt(byte[] plainBytes, KeyParameter aesKey) throws KeyCrypterException {
    checkNotNull(plainBytes);
    checkNotNull(aesKey);

    try {
        // Generate iv - each encryption call has a different iv.
        byte[] iv = new byte[BLOCK_LENGTH];
        secureRandom.nextBytes(iv);

        ParametersWithIV keyWithIv = new ParametersWithIV(aesKey, iv);

        // Encrypt using AES.
        BufferedBlockCipher cipher = new PaddedBufferedBlockCipher(new CBCBlockCipher(new AESFastEngine()));
        cipher.init(true, keyWithIv);
        byte[] encryptedBytes = new byte[cipher.getOutputSize(plainBytes.length)];
        final int length1 = cipher.processBytes(plainBytes, 0, plainBytes.length, encryptedBytes, 0);
        final int length2 = cipher.doFinal(encryptedBytes, length1);

        return new EncryptedData(iv, Arrays.copyOf(encryptedBytes, length1 + length2));
    } catch (Exception e) {
        throw new KeyCrypterException("Could not encrypt bytes.", e);
    }
}
 

/**
 * Decrypt bytes previously encrypted with this class.
 *
 * @param dataToDecrypt    The data to decrypt
 * @param aesKey           The AES key to use for decryption
 * @return                 The decrypted bytes
 * @throws                 KeyCrypterException if bytes could not be decrypted
 */
@Override
public byte[] decrypt(EncryptedData dataToDecrypt, KeyParameter aesKey) throws KeyCrypterException {
    checkNotNull(dataToDecrypt);
    checkNotNull(aesKey);

    try {
        ParametersWithIV keyWithIv = new ParametersWithIV(new KeyParameter(aesKey.getKey()), dataToDecrypt.initialisationVector);

        // Decrypt the message.
        BufferedBlockCipher cipher = new PaddedBufferedBlockCipher(new CBCBlockCipher(new AESFastEngine()));
        cipher.init(false, keyWithIv);

        byte[] cipherBytes = dataToDecrypt.encryptedBytes;
        byte[] decryptedBytes = new byte[cipher.getOutputSize(cipherBytes.length)];
        final int length1 = cipher.processBytes(cipherBytes, 0, cipherBytes.length, decryptedBytes, 0);
        final int length2 = cipher.doFinal(decryptedBytes, length1);

        return Arrays.copyOf(decryptedBytes, length1 + length2);
    } catch (Exception e) {
        throw new KeyCrypterException("Could not decrypt bytes", e);
    }
}
 

public static byte[] decrypt(ECPoint ephem, BigInteger prv, byte[] IV, byte[] cipher, byte[] macData) throws InvalidCipherTextException {
    AESFastEngine aesFastEngine = new AESFastEngine();

    EthereumIESEngine iesEngine = new EthereumIESEngine(
            new ECDHBasicAgreement(),
            new ConcatKDFBytesGenerator(new SHA256Digest()),
            new HMac(new SHA256Digest()),
            new SHA256Digest(),
            new BufferedBlockCipher(new SICBlockCipher(aesFastEngine)));


    byte[]         d = new byte[] {};
    byte[]         e = new byte[] {};

    IESParameters p = new IESWithCipherParameters(d, e, KEY_SIZE, KEY_SIZE);
    ParametersWithIV parametersWithIV =
            new ParametersWithIV(p, IV);

    iesEngine.init(false, new ECPrivateKeyParameters(prv, CURVE), new ECPublicKeyParameters(ephem, CURVE), parametersWithIV);

    return iesEngine.processBlock(cipher, 0, cipher.length, macData);
}
 

private static EthereumIESEngine makeIESEngine(boolean isEncrypt, ECPoint pub, BigInteger prv, byte[] IV) {
    AESFastEngine aesFastEngine = new AESFastEngine();

    EthereumIESEngine iesEngine = new EthereumIESEngine(
            new ECDHBasicAgreement(),
            new ConcatKDFBytesGenerator(new SHA256Digest()),
            new HMac(new SHA256Digest()),
            new SHA256Digest(),
            new BufferedBlockCipher(new SICBlockCipher(aesFastEngine)));


    byte[]         d = new byte[] {};
    byte[]         e = new byte[] {};

    IESParameters p = new IESWithCipherParameters(d, e, KEY_SIZE, KEY_SIZE);
    ParametersWithIV parametersWithIV = new ParametersWithIV(p, IV);

    iesEngine.init(isEncrypt, new ECPrivateKeyParameters(prv, CURVE), new ECPublicKeyParameters(pub, CURVE), parametersWithIV);
    return iesEngine;
}
 

public static EncryptedData encrypt(byte[] plainBytes, byte[] iv, KeyParameter aesKey) throws RuntimeException {
    Util.checkNotNull(plainBytes);
    Util.checkNotNull(aesKey);

    try {
        if (iv == null) {
            iv = EncryptedData.DEFAULT_IV;
            //SECURE_RANDOM.nextBytes(iv);
        }

        ParametersWithIV keyWithIv = new ParametersWithIV(aesKey, iv);

        // Encrypt using AES.
        BufferedBlockCipher cipher = new PaddedBufferedBlockCipher(new CBCBlockCipher(new AESFastEngine()));
        cipher.init(true, keyWithIv);
        byte[] encryptedBytes = new byte[cipher.getOutputSize(plainBytes.length)];
        final int length1 = cipher.processBytes(plainBytes, 0, plainBytes.length, encryptedBytes, 0);
        final int length2 = cipher.doFinal(encryptedBytes, length1);

        return new EncryptedData(iv, Arrays.copyOf(encryptedBytes, length1 + length2));
    } catch (Exception e) {
        throw new RuntimeException(e);
    }
}
 

public static byte[] decrypt(EncryptedData dataToDecrypt, KeyParameter aesKey) throws CryptoException {
    Util.checkNotNull(dataToDecrypt);
    Util.checkNotNull(aesKey);

    try {
        ParametersWithIV keyWithIv = new ParametersWithIV(new KeyParameter(aesKey.getKey()), dataToDecrypt.getInitialisationVector());

        // Decrypt the validator.
        BufferedBlockCipher cipher = new PaddedBufferedBlockCipher(new CBCBlockCipher(new AESFastEngine()));
        cipher.init(false, keyWithIv);

        byte[] cipherBytes = dataToDecrypt.getEncryptedBytes();
        byte[] decryptedBytes = new byte[cipher.getOutputSize(cipherBytes.length)];
        final int length1 = cipher.processBytes(cipherBytes, 0, cipherBytes.length, decryptedBytes, 0);
        final int length2 = cipher.doFinal(decryptedBytes, length1);

        return Arrays.copyOf(decryptedBytes, length1 + length2);
    } catch (Exception e) {
        throw new CryptoException();
    }
}
 

/**
 * Password based encryption using AES - CBC 256 bits.
 */
@Override
public EncryptedData encrypt(byte[] plainBytes, KeyParameter aesKey) throws KeyCrypterException {
    checkNotNull(plainBytes);
    checkNotNull(aesKey);

    try {
        // Generate iv - each encryption call has a different iv.
        byte[] iv = new byte[BLOCK_LENGTH];
        secureRandom.nextBytes(iv);

        ParametersWithIV keyWithIv = new ParametersWithIV(aesKey, iv);

        // Encrypt using AES.
        BufferedBlockCipher cipher = new PaddedBufferedBlockCipher(new CBCBlockCipher(new AESFastEngine()));
        cipher.init(true, keyWithIv);
        byte[] encryptedBytes = new byte[cipher.getOutputSize(plainBytes.length)];
        final int length1 = cipher.processBytes(plainBytes, 0, plainBytes.length, encryptedBytes, 0);
        final int length2 = cipher.doFinal(encryptedBytes, length1);

        return new EncryptedData(iv, Arrays.copyOf(encryptedBytes, length1 + length2));
    } catch (Exception e) {
        throw new KeyCrypterException("Could not encrypt bytes.", e);
    }
}
 

/**
 * Decrypt bytes previously encrypted with this class.
 *
 * @param dataToDecrypt    The data to decrypt
 * @param aesKey           The AES key to use for decryption
 * @return                 The decrypted bytes
 * @throws                 KeyCrypterException if bytes could not be decrypted
 */
@Override
public byte[] decrypt(EncryptedData dataToDecrypt, KeyParameter aesKey) throws KeyCrypterException {
    checkNotNull(dataToDecrypt);
    checkNotNull(aesKey);

    try {
        ParametersWithIV keyWithIv = new ParametersWithIV(new KeyParameter(aesKey.getKey()), dataToDecrypt.initialisationVector);

        // Decrypt the message.
        BufferedBlockCipher cipher = new PaddedBufferedBlockCipher(new CBCBlockCipher(new AESFastEngine()));
        cipher.init(false, keyWithIv);

        byte[] cipherBytes = dataToDecrypt.encryptedBytes;
        byte[] decryptedBytes = new byte[cipher.getOutputSize(cipherBytes.length)];
        final int length1 = cipher.processBytes(cipherBytes, 0, cipherBytes.length, decryptedBytes, 0);
        final int length2 = cipher.doFinal(decryptedBytes, length1);

        return Arrays.copyOf(decryptedBytes, length1 + length2);
    } catch (Exception e) {
        throw new KeyCrypterException("Could not decrypt bytes", e);
    }
}
 

/**
 * Decrypt bytes previously encrypted with this class.
 *
 * @param privateKeyToDecode The private key to decrypt
 * @param aesKey             The AES key to use for decryption
 * @return The decrypted bytes
 * @throws KeyCrypterException if bytes could not be decoded to a valid key
 */
@Override
public byte[] decrypt(EncryptedPrivateKey privateKeyToDecode, KeyParameter aesKey) throws KeyCrypterException {
    checkNotNull(privateKeyToDecode);
    checkNotNull(aesKey);

    try {
        ParametersWithIV keyWithIv = new ParametersWithIV(new KeyParameter(aesKey.getKey()), privateKeyToDecode.getInitialisationVector());

        // Decrypt the message.
        BufferedBlockCipher cipher = new PaddedBufferedBlockCipher(new CBCBlockCipher(new AESFastEngine()));
        cipher.init(false, keyWithIv);

        byte[] cipherBytes = privateKeyToDecode.getEncryptedBytes();
        int minimumSize = cipher.getOutputSize(cipherBytes.length);
        byte[] outputBuffer = new byte[minimumSize];
        int length1 = cipher.processBytes(cipherBytes, 0, cipherBytes.length, outputBuffer, 0);
        int length2 = cipher.doFinal(outputBuffer, length1);
        int actualLength = length1 + length2;

        byte[] decryptedBytes = new byte[actualLength];
        System.arraycopy(outputBuffer, 0, decryptedBytes, 0, actualLength);

        Utils.wipeBytes(outputBuffer);

        return decryptedBytes;
    } catch (Exception e) {
        throw new KeyCrypterException("Could not decrypt bytes", e);
    }
}