从CryptoStream就到流

Question

我遇到一些麻烦，下面的代码可以在读取。我有一个需要加密的临时位置的文件，这个函数会加密那些存储在“pathToSave”位置的数据。

在检查似乎并没有被正确地处理整个文件 - 有从我的输出失位，我怀疑它做的，而不是循环在整个流运行。

顺便说一句，如果我尝试和while循环后调用CryptStrm.Close（）我收到一个异常。这意味着如果我试图解密文件，我得到一个已经在使用中的文件错误！

尝试了所有的常用和伊夫这里看着在类似的问题，任何帮助将是巨大的。

感谢

public void EncryptFile(String tempPath, String pathToSave) 
    { 
     try 
     { 
      FileStream InputFile = new FileStream(tempPath, FileMode.Open, FileAccess.Read); 
      FileStream OutputFile = new FileStream(pathToSave, FileMode.Create, FileAccess.Write); 

      RijndaelManaged RijCrypto = new RijndaelManaged(); 

      //Key 
      byte[] Key = new byte[32] { ... }; 

      //Initialisation Vector 
      byte[] IV = new byte[32] { ... }; 

      RijCrypto.Padding = PaddingMode.None; 
      RijCrypto.KeySize = 256; 
      RijCrypto.BlockSize = 256; 
      RijCrypto.Key = Key; 
      RijCrypto.IV = IV; 

      ICryptoTransform Encryptor = RijCrypto.CreateEncryptor(Key, IV); 

      CryptoStream CryptStrm = new CryptoStream(OutputFile, Encryptor, CryptoStreamMode.Write); 

      int data; 
      while (-1 != (data = InputFile.ReadByte())) 
      { 
       CryptStrm.WriteByte((byte)data); 
      } 
     } 
     catch (Exception EncEx) 
     { 
      throw new Exception("Encoding Error: " + EncEx.Message); 
     } 
    } 

编辑：

我所做的假设，我的问题是加密。我的解密可能是罪魁祸首

 public String DecryptFile(String encryptedFilePath) 
    { 
     FileStream InputFile = new FileStream(encryptedFilePath, FileMode.Open, FileAccess.Read); 

     RijndaelManaged RijCrypto = new RijndaelManaged(); 

     //Key 
     byte[] Key = new byte[32] { ... }; 

     //Initialisation Vector 
     byte[] IV = new byte[32] { ... }; 

     RijCrypto.Padding = PaddingMode.None; 
     RijCrypto.KeySize = 256; 
     RijCrypto.BlockSize = 256; 
     RijCrypto.Key = Key; 
     RijCrypto.IV = IV; 

     ICryptoTransform Decryptor = RijCrypto.CreateDecryptor(Key, IV); 

     CryptoStream CryptStrm = new CryptoStream(InputFile, Decryptor, CryptoStreamMode.Read); 

     String OutputFilePath = Path.GetTempPath() + "myfile.name"; 
     StreamWriter OutputFile = new StreamWriter(OutputFilePath); 

     OutputFile.Write(new StreamReader(CryptStrm).ReadToEnd()); 

     CryptStrm.Close(); 
     OutputFile.Close(); 

     return OutputFilePath; 
    } 

Answer 1

好吧，这里有几件事情出错了。

1.您设置IV过大的尺寸。如果您的密钥大小为256，Rijndael的IV为16个字节。如果您尝试使用比该字节更多的字节来设置密钥，则会发生异常。 IV尺寸应设置为块尺寸/ 8 see MSDN，因此您拥有的IV尺寸是正确的。

您有无的填充模式。除非你的数据是正确的块大小，否则你将会遇到问题。您可能想要选择填充模式。

当您在加密时写入密码流时，通常需要调用FlushFInalBlock以确保将所有数据写入流中。

我发布了一些示例代码，使用内存流来显示加密和解密。

var tempData = "This is the text to encrypt. It's not much, but it's all there is."; 

using (var rijCrypto = new RijndaelManaged()) 
{ 
    byte[] encryptedData; 
    rijCrypto.Padding = System.Security.Cryptography.PaddingMode.ISO10126; 
    rijCrypto.KeySize = 256; 

    using (var input = new MemoryStream(Encoding.Unicode.GetBytes(tempData))) 
    using (var output = new MemoryStream()) 
    { 
     var encryptor = rijCrypto.CreateEncryptor(); 

     using (var cryptStream = new CryptoStream(output, encryptor, CryptoStreamMode.Write)) 
     { 
      var buffer = new byte[1024]; 
      var read = input.Read(buffer, 0, buffer.Length); 
      while (read > 0) 
      { 
       cryptStream.Write(buffer, 0, read); 
       read = input.Read(buffer, 0, buffer.Length); 
      } 
      cryptStream.FlushFinalBlock(); 
      encryptedData = output.ToArray(); 
     } 
    } 

    using (var input = new MemoryStream(encryptedData)) 
    using (var output = new MemoryStream()) 
    { 
     var decryptor = rijCrypto.CreateDecryptor(); 
     using (var cryptStream = new CryptoStream(input, decryptor, CryptoStreamMode.Read)) 
     { 
      var buffer = new byte[1024]; 
      var read = cryptStream.Read(buffer, 0, buffer.Length); 
      while (read > 0) 
      { 
       output.Write(buffer, 0, read); 
       read = cryptStream.Read(buffer, 0, buffer.Length); 
      } 
      cryptStream.Flush(); 
      var result = Encoding.Unicode.GetString(output.ToArray()); 
     } 
    } 
}