我的问题如下：
我有一个通过套接字连接的客户端/服务器应用程序。我客户的任务是按字节发送文件到服务器。服务器获取字节，将其解密，然后将其发送回客户端，然后将其写入磁盘上的新文件中。
每次在此代码行出现服务器端异常（System.Security.Cryptography.Exception：填充无效且无法删除）时，我都会收到此消息：plaintext = sr.ReadToEnd（）;
有人可以帮助我解决我的问题吗？
这是解密代码：
public byte[] Dec(byte[] content, byte[] Key, byte[] IV, int fileLength, string filepath, int chunkSize, int bytesToRead)
{
byte[] contentDec;
string plaintext = null;
System.Text.ASCIIEncoding encoding = new System.Text.ASCIIEncoding();
if (Key == null || Key.Length <= 0)
throw new ArgumentNullException("Key");
if (IV == null || IV.Length <= 0)
throw new ArgumentNullException("IV");
using (RijndaelManaged rijAlg = new RijndaelManaged())
{
rijAlg.Key = Key;
rijAlg.IV = IV;
ICryptoTransform decryptor = rijAlg.CreateDecryptor(rijAlg.Key, rijAlg.IV);
using (MemoryStream ms = new MemoryStream(content))
{
using (CryptoStream cs = new CryptoStream(ms, decryptor, CryptoStreamMode.Read))
{
using (StreamReader sr = new StreamReader(cs))
{
plaintext = sr.ReadToEnd();
cs.FlushFinalBlock();
}
contentDec = encoding.GetBytes(plaintext);
}
}
}
return contentDec;
}
这是我的加密代码：
public byte[] Enc(byte[] content,byte[] Key, byte[] IV, int fileLength,string filepath, int chunkSize, int bytesToRead)
{
byte[] contentEnc;
if (Key == null || Key.Length <= 0)
throw new ArgumentNullException("Key");
if (IV == null || IV.Length <= 0)
throw new ArgumentNullException("IV");
using (RijndaelManaged rijAlg = new RijndaelManaged())
{
rijAlg.Key = Key;
rijAlg.IV = IV;
ICryptoTransform encryptor = rijAlg.CreateEncryptor(rijAlg.Key, rijAlg.IV);
using (MemoryStream ms = new MemoryStream())
{
using (CryptoStream cs = new CryptoStream(ms, encryptor, CryptoStreamMode.Write))
{
using (StreamWriter sw = new StreamWriter(cs))
{
sw.Write(content);
}
contentEnc = ms.ToArray();
}
}
}
return contentEnc;
}
在客户端，我这样调用加密方法
int chunkSize = 1024;
byte[] chunk = new byte[chunkSize];
using (FileStream fileReader = new FileStream(plainPath, FileMode.Open, FileAccess.Read))
using (FileStream filewriter = new FileStream(pathEncrypt, FileMode.Create, FileAccess.ReadWrite))
using (BinaryReader binaryReader = new BinaryReader(fileReader))
using (RijndaelManaged myRijndael = new RijndaelManaged())
{
myRijndael.GenerateKey();
myRijndael.GenerateIV();
Key = myRijndael.Key;
IV = myRijndael.IV;
int bytesToRead = (int)fileReader.Length;
do
{
chunk = service.Enc(binaryReader.ReadBytes(chunkSize), Key, IV,(int)fileReader.Length,
fileReader.Name, chunkSize, bytesToRead);
filewriter.Write(chunk, 0, chunk.Length);
bytesToRead -= chunkSize;
} while (bytesToRead > 0);
}
密钥和IV声明为私有字节[]
在客户端，我这样调用解密方法
int chunkSize = 1024;
byte[] chunk = new byte[chunkSize];
using (FileStream fileReader = new FileStream(pathEncrypt, FileMode.Open, FileAccess.Read))
using (FileStream filewriter = new FileStream(pathDecrypt, FileMode.Create, FileAccess.ReadWrite))
using (BinaryReader binaryReader = new BinaryReader(fileReader))
{
int bytesToRead = (int)fileReader.Length;
do
{
chunk = service.Dec(binaryReader.ReadBytes(chunkSize), Key, IV, (int)fileReader.Length,
fileReader.Name, chunkSize, bytesToRead);
filewriter.Write(chunk, 0, chunk.Length);
bytesToRead -= chunkSize;
} while (bytesToRead > 0);
}
编辑：这是我在客户端和服务器之间的连接建立。
服务器： var host = new ServiceHost（typeof（Service）， 新的Uri（“ net.pipe：// localhost”））;
host.AddServiceEndpoint(typeof(TiService),
new NetNamedPipeBinding(), "TestService");
host.Open();
Console.WriteLine("Server connection established...");
Console.ReadKey();
客户：
var callback = new Callback();
var context = new InstanceContext(callback);
var pipeFactory =
new DuplexChannelFactory<TiService>(context,
new NetNamedPipeBinding(),
new EndpointAddress("net.pipe://localhost/TestService"));
service = pipeFactory.CreateChannel();
service.Connect();
答案 0 :(得分：0)
您的问题开始于在加密中使用StreamWriter。它用于写文本文件，而不是任意文件。当您调用sw.Write（content）时，它仅调用content.ToString（），它返回“ System.Byte []”，而不是您可能期望的数组的每个字节。要解决此问题，只需编写CryptoStream，无需使用StreamWriter，如下所示：
using (var rijAlg = new AesCng())
{
rijAlg.Key = Key;
rijAlg.IV = IV;
ICryptoTransform encryptor = rijAlg.CreateEncryptor();
using (MemoryStream ms = new MemoryStream())
{
using (CryptoStream cs = new CryptoStream(ms, encryptor, CryptoStreamMode.Write))
{
cs.Write(content, 0, content.Length);
}
contentEnc = ms.ToArray();
}
}
您可能注意到我使用AesCng而不是RijndaelManaged。为什么？因为在我的测试中它要快得多，并且除非您真的需要非标准块，否则使用RijndaelManaged没有任何好处。另外，我使用无参数的CreateEncryptor，因为无论如何您已经在前几行中设置了Key＆IV。
解密中的处理相同。您不应该将它们视为文本，因此：
var buffer = new byte[content.Length]; //at first its size is actual size+padding
using (var rijAlg = new AesCng())
{
rijAlg.Key = Key;
rijAlg.IV = IV;
ICryptoTransform decryptor = rijAlg.CreateDecryptor();
using (MemoryStream ms = new MemoryStream(content))
{
using (CryptoStream cs = new CryptoStream(ms, decryptor, CryptoStreamMode.Read))
{
var actualSize = cs.Read(buffer, 0, content.Length);
//we write the decrypted content to the buffer, and get the actual size
Array.Resize(ref buffer, actualSize);
//then we resize the buffer to the actual size
}
}
}
return buffer;
此外，您对Enc和Dec的使用不必要地复杂。它已经能够自己处理整个文件。因此，要加密文件，只需使用
var original = File.ReadAllBytes("originalPath");
var enc = Enc(original, rM.Key, rM.IV);
File.WriteAllBytes("encryptedPath", enc);
要解密文件，只需使用
var enc = File.ReadAllBytes("encryptedPath");
var dec = Dec(enc, rM.Key, rM.IV);
File.WriteAllBytes("decryptedPath", dec);
如您所见，我丢弃了Enc＆Dec上的fileLength，filepath，chunkSize和bytesToRead，因为您当前的代码实际上并没有使用它们。我已经尝试过使用ASCII，Unicode和UTF-8上的短文本文件以及大型二进制文件进行代码编码，所有这些文件均已成功加密和解密，并且最终解密的文件具有相同的哈希值。
编辑：
将代码转换为直接的文件流写操作实际上使一切变得更加简单。
public static void Transform(string source, string target, ICryptoTransform transf)
{
var bufferSize = 65536;
var buffer = new byte[bufferSize];
using (var sourceStream = new FileStream(source, FileMode.Open))
{
using (var targetStream = new FileStream(target, FileMode.OpenOrCreate))
{
using (CryptoStream cs = new CryptoStream(targetStream, transf, CryptoStreamMode.Write))
{
var bytesRead = 0;
do
{
bytesRead = sourceStream.Read(buffer, 0, bufferSize);
cs.Write(buffer, 0, bytesRead);
} while (bytesRead != 0);
}
}
}
}
public static void Enc(string source, byte[] Key, byte[] IV, string target)
{
using (var rijAlg = new AesCng())
{
rijAlg.Key = Key;
rijAlg.IV = IV;
ICryptoTransform encryptor = rijAlg.CreateEncryptor();
Transform(source, target, encryptor);
}
}
public static void Dec(string source, byte[] Key, byte[] IV, string target)
{
using (var rijAlg = new AesCng())
{
rijAlg.Key = Key;
rijAlg.IV = IV;
ICryptoTransform decryptor = rijAlg.CreateDecryptor();
Transform(source, target, decryptor);
}
}
用法是：
Enc(@"originalPath", key, iv, @"encryptedPath");
Dec(@"encrypedPath", key, iv, @"decryptedPath");