Java Code Examples for org.bouncycastle.crypto.paddings.PaddedBufferedBlockCipher#getOutputSize()

@Override
public byte[] aesEncrypt(byte[] plaintext, byte[] signingKey, byte[] nonce) {
    if (signingKey.length != 32) {
        throw new IllegalArgumentException("Key length must be 32 bytes");
    }
    try {
        for (int i = 0; i < 32; i++) {
            signingKey[i] ^= nonce[i];
        }
        byte[] key = getSha256().digest(signingKey);
        byte[] iv = new byte[16];
        secureRandom.nextBytes(iv);
        PaddedBufferedBlockCipher aes = new PaddedBufferedBlockCipher(new CBCBlockCipher(new AESEngine()));
        CipherParameters ivAndKey = new ParametersWithIV(new KeyParameter(key), iv);
        aes.init(true, ivAndKey);
        byte[] output = new byte[aes.getOutputSize(plaintext.length)];
        int ciphertextLength = aes.processBytes(plaintext, 0, plaintext.length, output, 0);
        ciphertextLength += aes.doFinal(output, ciphertextLength);
        byte[] result = new byte[iv.length + ciphertextLength];
        System.arraycopy(iv, 0, result, 0, iv.length);
        System.arraycopy(output, 0, result, iv.length, ciphertextLength);
        return result;
    } catch (InvalidCipherTextException e) {
        throw new RuntimeException(e.getMessage(), e);
    }
}
 

@Override
public byte[] aesDecrypt(byte[] encrypted, byte[] signingKey, byte[] nonce) {
    if (signingKey.length != 32) {
        throw new IllegalArgumentException("Key length must be 32 bytes");
    }
    try {
        if (encrypted.length < 16 || encrypted.length % 16 != 0) {
            throw new InvalidCipherTextException("invalid ciphertext");
        }
        byte[] iv = Arrays.copyOfRange(encrypted, 0, 16);
        byte[] ciphertext = Arrays.copyOfRange(encrypted, 16, encrypted.length);
        for (int i = 0; i < 32; i++) {
            signingKey[i] ^= nonce[i];
        }
        byte[] key = getSha256().digest(signingKey);
        PaddedBufferedBlockCipher aes = new PaddedBufferedBlockCipher(new CBCBlockCipher(new AESEngine()));
        CipherParameters ivAndKey = new ParametersWithIV(new KeyParameter(key), iv);
        aes.init(false, ivAndKey);
        byte[] output = new byte[aes.getOutputSize(ciphertext.length)];
        int plaintextLength = aes.processBytes(ciphertext, 0, ciphertext.length, output, 0);
        plaintextLength += aes.doFinal(output, plaintextLength);
        byte[] result = new byte[plaintextLength];
        System.arraycopy(output, 0, result, 0, result.length);
        return result;
    } catch (InvalidCipherTextException e) {
        throw new RuntimeException(e.getMessage(), e);
    }
}
 

/**
 * Encrypt.
 *
 * @param instr the instr
 * @return the string
 * @throws java.security.GeneralSecurityException the general security exception
 */
@Override
public String encrypt(String instr) throws GeneralSecurityException {
    long t1 = System.currentTimeMillis();
    byte[] in = instr.getBytes();
    PaddedBufferedBlockCipher encryptor = new PaddedBufferedBlockCipher(
            new CBCBlockCipher(new DESedeEngine()));
    encryptor.init(true, keyParameter);
    byte[] cipherText = new byte[encryptor.getOutputSize(in.length)];
    int outputLen = encryptor.processBytes(in, 0, in.length, cipherText, 0);
    ByteArrayOutputStream os = new ByteArrayOutputStream();
    try {
        encryptor.doFinal(cipherText, outputLen);
        Hex.encode(cipherText, os);
    } catch (Exception e) {
        e.printStackTrace();
        throw new GeneralSecurityException(e);
    }
    long t2 = System.currentTimeMillis();
    logger.debug("Time taken to encrypt(millis) :" + (t2 - t1));
    return ENC_PREFIX + os.toString();
}
 

private String decryptStr(String instr) throws GeneralSecurityException {
    if(StringUtils.isEmpty(instr)){
        return instr;
    }
    long t1 = System.currentTimeMillis();
    PaddedBufferedBlockCipher decryptor = new PaddedBufferedBlockCipher(
            new CBCBlockCipher(new DESedeEngine()));
    decryptor.init(false, keyParameter);
    byte[] in = null;
    byte[] cipherText = null;

    try {
    	in = Hex.decode(instr);
    	cipherText = new byte[decryptor.getOutputSize(in.length)];

     int outputLen = decryptor.processBytes(in, 0, in.length, cipherText, 0);
        decryptor.doFinal(cipherText, outputLen);
    } catch (Exception e) {
        throw new GeneralSecurityException(e);
    }
    long t2 = System.currentTimeMillis();
    logger.debug("Time taken to decrypt(millis) : " + (t2 - t1));
    return (new String(cipherText)).replaceAll("\\u0000+$", "");
}
 

public static byte[] decryptAESCBC(byte[] key, byte[] iv, byte[] data) {
    // AES CBC PKCS7 decrypt
    try {
        CipherParameters cipherParameters = new ParametersWithIV(new KeyParameter(key), iv);
        PaddedBufferedBlockCipher cipher
                = new PaddedBufferedBlockCipher(new CBCBlockCipher(new AESFastEngine()), new PKCS7Padding());
        cipher.init(false, cipherParameters);

        byte[] buffer = new byte[cipher.getOutputSize(data.length)];

        int pos = cipher.processBytes(data, 0, data.length, buffer, 0);
        pos += cipher.doFinal(buffer, pos);

        return Arrays.copyOf(buffer, pos);

    } catch (DataLengthException | IllegalStateException | InvalidCipherTextException ex) {
        throw new IllegalArgumentException("decrypt failed", ex);
    }
}
 

private static String decrypt(byte[] key, String cipherText) throws CryptoException {
    try {
        PaddedBufferedBlockCipher cipher = new PaddedBufferedBlockCipher(new CBCBlockCipher(new DESEngine()));
        cipher.init(false, new KeyParameter(key));
        byte[] cipherTextBytes = DECODER.decode(cipherText);

        byte[] plainTextBytes = new byte[cipher.getOutputSize(cipherTextBytes.length)];
        int outputLength = cipher.processBytes(cipherTextBytes, 0, cipherTextBytes.length, plainTextBytes, 0);
        cipher.doFinal(plainTextBytes, outputLength);
        int paddingStarts = plainTextBytes.length - 1;
        for (; paddingStarts >= 0; paddingStarts--) {
            if (plainTextBytes[paddingStarts] != 0) {
                break;
            }
        }
        return new String(plainTextBytes, 0, paddingStarts + 1);
    } catch (Exception e) {
        throw new CryptoException(e);
    }
}
 

private static byte[] processAESCipher(boolean encrypt, byte[] data, SecretKey key, byte[] initVector)
		throws DataLengthException, IllegalStateException, InvalidCipherTextException {
	// seat up engine, block cipher mode and padding
	AESEngine aesEngine = new AESEngine();
	CBCBlockCipher cbc = new CBCBlockCipher(aesEngine);
	PaddedBufferedBlockCipher cipher = new PaddedBufferedBlockCipher(cbc);

	// apply parameters
	CipherParameters parameters = new ParametersWithIV(new KeyParameter(key.getEncoded()), initVector);
	cipher.init(encrypt, parameters);

	// process ciphering
	byte[] output = new byte[cipher.getOutputSize(data.length)];

	int bytesProcessed1 = cipher.processBytes(data, 0, data.length, output, 0);
	int bytesProcessed2 = cipher.doFinal(output, bytesProcessed1);
	byte[] result = new byte[bytesProcessed1 + bytesProcessed2];
	System.arraycopy(output, 0, result, 0, result.length);
	return result;
}
 

private static String encrypt(byte[] key, String plainText) throws CryptoException {
    try {
        PaddedBufferedBlockCipher cipher = new PaddedBufferedBlockCipher(new CBCBlockCipher(new DESEngine()));
        KeyParameter keyParameter = new KeyParameter(key);
        cipher.init(true, keyParameter);
        byte[] plainTextBytes = plainText.getBytes();
        byte[] cipherTextBytes = new byte[cipher.getOutputSize(plainTextBytes.length)];
        int outputLength = cipher.processBytes(plainTextBytes, 0, plainTextBytes.length, cipherTextBytes, 0);
        cipher.doFinal(cipherTextBytes, outputLength);
        return ENCODER.encodeToString(cipherTextBytes).trim();
    } catch (Exception e) {
        throw new CryptoException(e);
    }
}
 

private static byte[] cipherData(PaddedBufferedBlockCipher cipher, byte[] data)
        throws IllegalStateException, InvalidCipherTextException {
    int minSize = cipher.getOutputSize(data.length);
    byte[] outBuf = new byte[minSize];
    int length1 = cipher.processBytes(data, 0, data.length, outBuf, 0);
    int length2 = cipher.doFinal(outBuf, length1);
    int actualLength = length1 + length2;
    if (actualLength == minSize) {
        return outBuf;
    } else {
        return Arrays.copyOf(outBuf, actualLength);
    }
}