使用 Rijndael 加密/解密文件

我需要传输 xml 文件，并且需要对它们进行加密。我发现一些例子认为我已经接近了，但是当我解密文件时，我最终得到了尾随垃圾字符。有一些关于此的帖子，但我还没有看到任何能真正有帮助的帖子。这是加密和解密代码。

private void EncryptFile(string inputFile, string outputFile, string key) {
    try {
        byte[] keyBytes;
        keyBytes = Encoding.Unicode.GetBytes(key);

        Rfc2898DeriveBytes derivedKey = new Rfc2898DeriveBytes(key, keyBytes);

        RijndaelManaged rijndaelCSP = new RijndaelManaged();
        rijndaelCSP.Key = derivedKey.GetBytes(rijndaelCSP.KeySize / 8);
        rijndaelCSP.IV = derivedKey.GetBytes(rijndaelCSP.BlockSize / 8);

        ICryptoTransform encryptor = rijndaelCSP.CreateEncryptor();

        FileStream inputFileStream = new FileStream(inputFile, FileMode.Open, FileAccess.Read);

        byte[] inputFileData = new byte[(int)inputFileStream.Length];
        inputFileStream.Read(inputFileData, 0, (int)inputFileStream.Length);

        FileStream outputFileStream = new FileStream(outputFile, FileMode.Create, FileAccess.Write);

        CryptoStream encryptStream = new CryptoStream(outputFileStream, encryptor, CryptoStreamMode.Write);
        encryptStream.Write(inputFileData, 0, (int)inputFileStream.Length);
        encryptStream.FlushFinalBlock();

        rijndaelCSP.Clear();
        encryptStream.Close();
        inputFileStream.Close();
        outputFileStream.Close();
    }
    catch (Exception ex) {
        MessageBox.Show(ex.Message, "Encryption Failed!", MessageBoxButtons.OK, MessageBoxIcon.Error);
        return;
    }

    MessageBox.Show("File Encryption Complete!");

}

private void DecryptFile(string inputFile, string outputFile, string key) {
    try {
        byte[] keyBytes = Encoding.Unicode.GetBytes(key);

        Rfc2898DeriveBytes derivedKey = new Rfc2898DeriveBytes(key, keyBytes);

        RijndaelManaged rijndaelCSP = new RijndaelManaged();
        rijndaelCSP.Key = derivedKey.GetBytes(rijndaelCSP.KeySize / 8);
        rijndaelCSP.IV = derivedKey.GetBytes(rijndaelCSP.BlockSize / 8);
        ICryptoTransform decryptor = rijndaelCSP.CreateDecryptor();

        FileStream inputFileStream = new FileStream(inputFile, FileMode.Open, FileAccess.Read);

        CryptoStream decryptStream = new CryptoStream(inputFileStream, decryptor, CryptoStreamMode.Read);

        byte[] inputFileData = new byte[(int)inputFileStream.Length];
        decryptStream.Read(inputFileData, 0, (int)inputFileStream.Length);

        FileStream outputFileStream = new FileStream(outputFile, FileMode.Create, FileAccess.Write);
        outputFileStream.Write(inputFileData, 0, inputFileData.Length);
        outputFileStream.Flush();

        rijndaelCSP.Clear();

        decryptStream.Close();
        inputFileStream.Close();
        outputFileStream.Close();
    }
    catch (Exception ex) {
        MessageBox.Show(ex.Message, "Decryption Failed!", MessageBoxButtons.OK, MessageBoxIcon.Error);
        return;
    }

    MessageBox.Show("File Decryption Complete!");
}

我最终得到

<?xml version="1.0" encoding="UTF-8"?>
<transaction>
  <header>
    <qOrderNumber></qOrderNumber>
    <qRequestDate></qRequestDate>
    <testOrder></testOrder>
    <qCustomerNumber></qCustomerNumber>
    <transactionStatus></transactionStatus>
  </header>
  <lines>
    <line>
      <productID></productID>
      <serialNumber></serialNumber>
    </line>
    <line> 
      <productID></productID>
      <serialNumber></serialNumber>
    </line>
  </lines>
</transaction>NULNULNULNULNULNUL

解密时，请注意 CryptoStream.Read 调用的返回值。它告诉您字节数组中解密数据的长度（通常由于填充而与加密数据的长度不匹配）。尝试在解密函数中使用以下内容：

int decrypt_length = decryptStream.Read(inputFileData, 0, (int)inputFileStream.Length);
FileStream outputFileStream = new FileStream(outputFile, FileMode.Create, FileAccess.Write);
outputFileStream.Write(inputFileData, 0, decrypt_length);