Question

我正在尝试模拟非对称密钥系统。我使用以下代码生成密钥对，加密，解密密码。我有一个分布式环境，目前我保存在文件系统中生成的密钥。我知道这不安全，但仅用于测试目的。

    private static SecureRandom random = new SecureRandom();

    static {
        Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());
    }

    protected synchronized void generateKeys() throws InvalidKeyException, IllegalBlockSizeException, 
            BadPaddingException, NoSuchAlgorithmException, NoSuchProviderException, 
                NoSuchPaddingException {

        KeyPairGenerator generator = KeyPairGenerator.getInstance("RSA", "BC");

        generator.initialize(256, random);

        KeyPair pair = generator.generateKeyPair();
        Key pubKey = pair.getPublic();
        Key privKey = pair.getPrivate();

        //store public key
        try {
            storeKey(pubKey, Constants.KEY_PATH.concat(Constants.SERVER_PREFIX.concat("-publickey")));
        } catch (Exception e) {
            e.printStackTrace();
            DBLogger.logMessage(e.toString(), Status.KEY_GENERATION_ERROR);
        } 

        //store private key
        try {
            storeKey(privKey, Constants.KEY_PATH.concat(Constants.SERVER_PREFIX.concat("-privatekey")));
        } catch (Exception e) {
            e.printStackTrace();
            DBLogger.logMessage(e.toString(), Status.KEY_GENERATION_ERROR);
        } 
    }

    protected synchronized String encryptUsingPublicKey(String plainText) throws IllegalBlockSizeException, BadPaddingException, 
        NoSuchAlgorithmException, NoSuchProviderException, NoSuchPaddingException, InvalidKeyException, 
            FileNotFoundException, IOException, ClassNotFoundException {

        Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding", "BC");
        cipher.init(Cipher.ENCRYPT_MODE, readKey(Constants.KEY_PATH.concat(Constants.SERVER_PREFIX.concat("-publickey"))), random);
        byte[] cipherText = cipher.doFinal(plainText.getBytes());
        System.out.println("cipher: " + new String(cipherText));    

        return new String(cipherText);
    }

    protected synchronized String decryptUsingPrivatekey(String cipherText) throws NoSuchAlgorithmException, 
        NoSuchProviderException, NoSuchPaddingException, InvalidKeyException, FileNotFoundException, 
            IOException, ClassNotFoundException, IllegalBlockSizeException, BadPaddingException {

        Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding", "BC");
        cipher.init(Cipher.DECRYPT_MODE, readKey(Constants.KEY_PATH.concat(Constants.SERVER_PREFIX.concat("-privatekey"))));
        byte[] plainText = cipher.doFinal(cipherText.getBytes());
        System.out.println("plain : " + new String(plainText));

        return new String(plainText);
    }
    public static void main(String[] args) {
        KeyGenerator keyGenerator = new KeyGenerator();
        try {
            keyGenerator.deleteAllKeys(Constants.KEY_PATH);
            keyGenerator.generateKeys();

            String cipherText = keyGenerator.encryptUsingPrivateKey("dilshan");
            keyGenerator.decryptUsingPublickey(cipherText);

//          String cipherText = keyGenerator.encryptUsingPublicKey("dilshan1");
//          keyGenerator.decryptUsingPrivatekey(cipherText);
        } catch (Exception e) {
            e.printStackTrace();
            DBLogger.logMessage(e.toString(), Status.KEY_GENERATION_ERROR);
        }
    }

这在大多数时候都非常有效。但有时它会产生以下错误。偶尔会发生这种情况。大部分时间这是有效的，所以我没有问题是代码。我相信这与文件系统的序列化/序列化过程有关。感谢帮助。

注意：我正在使用bouncycastle。

错误如下，

javax.crypto.BadPaddingException: unknown block type
    at org.bouncycastle.jcajce.provider.asymmetric.rsa.CipherSpi.engineDoFinal(Unknown Source)
    at javax.crypto.Cipher.doFinal(DashoA13*..)
    at com.dilshan.ttp.web.KeyGenerator.decryptUsingPublickey(KeyGenerator.java:105)
    at com.dilshan.ttp.web.KeyGenerator.main(KeyGenerator.java:150)

发生在，

byte[] plainText = cipher.doFinal(cipherText.getBytes());

在decryptUsingPrivatekey方法中。

Answer 1

密文是二进制数据。如果使用默认编码将其转换为String，则很可能遇到无法用字符表示的字节序列。因此，在解密期间，当您将String转换回字节数组时，您不会得到相同的字节，并且解密失败。

要解决此问题，请不要将密文转换为字符串，而是将字节[]转换为。

javax.crypto.BadPaddingException：未知块类型

1 个答案: