Java 为什么加密失败了？

我在加密网站上找到了以下代码。。。它作为Java客户机和C服务器工作。这段代码工作得很好，但有一个问题我无法解决。如果我发送小消息，一切都很好。。。当我向服务器发送超过47个字符时，问题就开始了。此时，它失败，出现以下错误：

输入不是有效的Base-64字符串，因为它包含非Base-64字符、两个以上的填充字符或填充字符中的非法字符

有人可以检查一下，或者自己测试一下，然后找到解决方案……谢谢

Java代码：

public class Crypto {

private final String characterEncoding = "UTF-8";
private final String cipherTransformation = "AES/CBC/PKCS5Padding";
private final String aesEncryptionAlgorithm = "AES";

public  byte[] decrypt(byte[] cipherText, byte[] key, byte [] initialVector) throws NoSuchAlgorithmException, NoSuchPaddingException, InvalidKeyException, InvalidAlgorithmParameterException, IllegalBlockSizeException, BadPaddingException
{
    Cipher cipher = Cipher.getInstance(cipherTransformation);
    SecretKeySpec secretKeySpecy = new SecretKeySpec(key, aesEncryptionAlgorithm);
    IvParameterSpec ivParameterSpec = new IvParameterSpec(initialVector);
    cipher.init(Cipher.DECRYPT_MODE, secretKeySpecy, ivParameterSpec);
    cipherText = cipher.doFinal(cipherText);
    return cipherText;
}

public byte[] encrypt(byte[] plainText, byte[] key, byte [] initialVector) throws NoSuchAlgorithmException, NoSuchPaddingException, InvalidKeyException, InvalidAlgorithmParameterException, IllegalBlockSizeException, BadPaddingException
{
    Cipher cipher = Cipher.getInstance(cipherTransformation);
    SecretKeySpec secretKeySpec = new SecretKeySpec(key, aesEncryptionAlgorithm);
    IvParameterSpec ivParameterSpec = new IvParameterSpec(initialVector);
    cipher.init(Cipher.ENCRYPT_MODE, secretKeySpec, ivParameterSpec);
    plainText = cipher.doFinal(plainText);
    return plainText;
}

private byte[] getKeyBytes(String key) throws UnsupportedEncodingException{
    byte[] keyBytes= new byte[16];
    byte[] parameterKeyBytes= key.getBytes(characterEncoding);
    System.arraycopy(parameterKeyBytes, 0, keyBytes, 0, Math.min(parameterKeyBytes.length, keyBytes.length));
    return keyBytes;
}

/// <summary>
/// Encrypts plaintext using AES 128bit key and a Chain Block Cipher and returns a base64 encoded string
/// </summary>
/// <param name="plainText">Plain text to encrypt</param>
/// <param name="key">Secret key</param>
/// <returns>Base64 encoded string</returns>
public String encrypt(String plainText, String key) throws UnsupportedEncodingException, InvalidKeyException, NoSuchAlgorithmException, NoSuchPaddingException, InvalidAlgorithmParameterException, IllegalBlockSizeException, BadPaddingException{
    byte[] plainTextbytes = plainText.getBytes(characterEncoding);
    byte[] keyBytes = getKeyBytes(key);
    return Base64.encodeToString(encrypt(plainTextbytes,keyBytes, keyBytes), Base64.DEFAULT);
}

/// <summary>
/// Decrypts a base64 encoded string using the given key (AES 128bit key and a Chain Block Cipher)
/// </summary>
/// <param name="encryptedText">Base64 Encoded String</param>
/// <param name="key">Secret Key</param>
/// <returns>Decrypted String</returns>
public String decrypt(String encryptedText, String key) throws KeyException, GeneralSecurityException, GeneralSecurityException, InvalidAlgorithmParameterException, IllegalBlockSizeException, BadPaddingException, IOException{
    byte[] cipheredBytes = Base64.decode(encryptedText, Base64.DEFAULT);
    byte[] keyBytes = getKeyBytes(key);
    return new String(decrypt(cipheredBytes, keyBytes, keyBytes), characterEncoding);
}

C代码：

class Crypto
{
    public static string currentPassword;

    public RijndaelManaged GetRijndaelManaged(String secretKey)
    {
        var keyBytes = new byte[16];
        var secretKeyBytes = Encoding.UTF8.GetBytes(secretKey);
        Array.Copy(secretKeyBytes, keyBytes, Math.Min(keyBytes.Length, secretKeyBytes.Length));
        return new RijndaelManaged
        {
            Mode = CipherMode.CBC,
            Padding = PaddingMode.PKCS7,
            KeySize = 128,
            BlockSize = 128,
            Key = keyBytes,
            IV = keyBytes
        };
    }

    public byte[] Encrypt(byte[] plainBytes, RijndaelManaged rijndaelManaged)
    {
        return rijndaelManaged.CreateEncryptor()
            .TransformFinalBlock(plainBytes, 0, plainBytes.Length);
    }

    public byte[] Decrypt(byte[] encryptedData, RijndaelManaged rijndaelManaged)
    {
        return rijndaelManaged.CreateDecryptor()
            .TransformFinalBlock(encryptedData, 0, encryptedData.Length);
    }

    /// <summary>
    /// Encrypts plaintext using AES 128bit key and a Chain Block Cipher and returns a base64 encoded string
    /// </summary>
    /// <param name="plainText">Plain text to encrypt</param>
    /// <param name="key">Secret key</param>
    /// <returns>Base64 encoded string</returns>
    public String Encrypt(String plainText, String key)
    {
        var plainBytes = Encoding.UTF8.GetBytes(plainText);
        return Convert.ToBase64String(Encrypt(plainBytes, GetRijndaelManaged(key)));
    }

    /// <summary>
    /// Decrypts a base64 encoded string using the given key (AES 128bit key and a Chain Block Cipher)
    /// </summary>
    /// <param name="encryptedText">Base64 Encoded String</param>
    /// <param name="key">Secret Key</param>
    /// <returns>Decrypted String</returns>
    public String Decrypt(String encryptedText, String key)
    {
        var encryptedBytes = Convert.FromBase64String(encryptedText);
        return Encoding.UTF8.GetString(Decrypt(encryptedBytes, GetRijndaelManaged(key)));
    }
}

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逐字节检查您发送的内容。Base64字符串中可能插入了一些换行符，这将给出您看到的结果。您可能需要明确地将Base64切分为几行，然后在接收端重新组装。实际上我已经这样做了。。。有趣的是，我说过，如果我发送小块数据，一切都好。任何超过47个字符的都会失败。。。非常奇怪。我正在做的就是切掉换行符，但如果我发送任何超过47个字符的内容，它就会失败，然后说要解密的数据长度无效。我在Java客户端和C后端遇到了一个类似的问题。我交换了用Java生成的RSA密钥，我必须切掉第一个字节，才能使它们在c中工作。尝试检查字节数组。我知道了发生了什么，因为某种原因，在一定数量的char java广告中，在加密文本的中间…所以当我在c中切碎时，我无意中删除了一半的信息。。。我需要做的是在\n \n处切掉，这是消息的实际结尾，而不仅仅是像我说的那样删除了消息的一部分。但是我不明白为什么java要添加这个换行符。