Rijndael 解密错误 - 要解密的数据长度无效

Question

我可以使用 rijndeal 加密 zip 文件，但是当我解密时，我收到一条错误，提示“要解密的数据长度无效”，我正在从文件中获取要解密的字节数组。这是我获取字节数组的方法。

Dim FStream As FileStream = File.OpenRead("<Filepath>")
EncData = New Byte(FStream.Length) {}
FStream.Read(EncData, 0, EncData.Length)
Dim DecryptedBytes As Byte() = DataVault.RijndealController.Decrypt(EncData, Password)

一旦我将字节数组传递到 Decrypt 方法中，当我尝试使用加密流读取时，就会收到错误。

Public Function Decrypt(ByVal Input As Byte(), ByVal Password As String) As Byte()

 Try
   Dim PasswordBytes As Byte() = Encoding.UTF8.GetBytes(Password)
   Dim initVectorBytes As Byte() = Encoding.ASCII.GetBytes("@0B4c3D4e5Y6r7H2")
   Dim SaltValue As Byte() = Encoding.UTF8.GetBytes("S@ltVa|u<")


   Dim DerivedBytes As Rfc2898DeriveBytes = New Rfc2898DeriveBytes(PasswordBytes,SaltValue, 4)
   Dim keyBytes As Byte() = DerivedBytes.GetBytes(32)

 Dim symmetricKey As RijndaelManaged
 symmetricKey = New RijndaelManaged()
 symmetricKey.Mode = CipherMode.CBC

 Dim decryptor As ICryptoTransform
 decryptor = symmetricKey.CreateDecryptor(keyBytes, initVectorBytes)

 Dim memoryStream As MemoryStream
 memoryStream = New MemoryStream(Input)

 Dim cryptoStream As CryptoStream
 cryptoStream = New CryptoStream(memoryStream, decryptor, CryptoStreamMode.Read)

 Dim plainTextBytes As Byte()
 ReDim plainTextBytes(Input.Length)


 Dim decryptedByteCount As Integer
While ((decryptedByteCount = cryptoStream.Read(plainTextBytes, 0, plainTextBytes.Length)) > 0)

 End While

memoryStream.Close()
cryptoStream.Close()

Return plainTextBytes

Catch ex As Exception
 Return Nothing
End Try

End Function

有什么想法我做错了什么吗？

这也是他们加密的代码：

        Public Function EncryptBytes(ByVal Input As Byte(), ByVal Password As String) As Byte()

        Try
            Dim PasswordBytes As Byte() = Encoding.UTF8.GetBytes(Password)
            Dim initVectorBytes As Byte() = Encoding.ASCII.GetBytes("@0B4c3D4e5Y6r7H2")
            Dim SaltValue As Byte() = Encoding.UTF8.GetBytes("S@ltVa|u<")
            Dim InputStringBytes As Byte() = Input

            Dim DerivedBytes As Rfc2898DeriveBytes = New Rfc2898DeriveBytes(PasswordBytes, SaltValue, 4)
            Dim keyBytes As Byte() = DerivedBytes.GetBytes(32)


            Dim symmetricKey As RijndaelManaged
            symmetricKey = New RijndaelManaged
            symmetricKey.Mode = CipherMode.CBC

            Dim encryptor As ICryptoTransform
            encryptor = symmetricKey.CreateEncryptor(keyBytes, initVectorBytes)
            Dim MStream As New MemoryStream()

            Dim cryptoStream As CryptoStream
            cryptoStream = New CryptoStream(MStream, encryptor, CryptoStreamMode.Write)
            cryptoStream.Write(InputStringBytes, 0, InputStringBytes.Length)
            cryptoStream.FlushFinalBlock()

            Dim cipherBytes As Byte() = MStream.ToArray()
            MStream.Close()
            cryptoStream.Close()

            Return cipherBytes

        Catch ex As Exception

        End Try
        Return Encoding.UTF8.GetBytes("0")
    End Function

Answer 1

将文件流代码替换为 System.IO.File.ReadAllBytes、System.IO.File.WriteAllBytes。如果这有效，那么您就知道文件流导致了问题。

Answer 2

您如何保存加密数据？您是使用纯文本（即 ASCII、UTF-8 等）对其进行编码，还是使用 Base-64 之类的内容对其进行编码？尝试将其加密为字节数组，然后立即解密。如果它有效并且解密成功，则说明存在编码问题。

Answer 3

这修复了它：

    Public Function EncryptBytes(ByVal Input As Byte(), ByVal Password As String) As Byte()

        Try
            Dim PasswordBytes As Byte() = Encoding.UTF8.GetBytes(Password)
            Dim initVectorBytes As Byte() = Encoding.ASCII.GetBytes("@0B4c3D4e5Y6r7H2")
            Dim SaltValue As Byte() = Encoding.UTF8.GetBytes("S@ltVa|u<")
            Dim InputStringBytes As Byte() = Input

            Dim DerivedBytes As Rfc2898DeriveBytes = New Rfc2898DeriveBytes(PasswordBytes, SaltValue, 4)
            Dim keyBytes As Byte() = DerivedBytes.GetBytes(32)

            'Generate Rijndael Manager
            Dim symmetricKey As RijndaelManaged
            symmetricKey = New RijndaelManaged
            symmetricKey.Mode = CipherMode.CBC

            Dim encryptor As ICryptoTransform
            encryptor = symmetricKey.CreateEncryptor(keyBytes, initVectorBytes)
            Dim MStream As New MemoryStream()

            Dim cryptoStream As CryptoStream
            cryptoStream = New CryptoStream(MStream, encryptor, CryptoStreamMode.Write)
            cryptoStream.Write(InputStringBytes, 0, InputStringBytes.Length)
            cryptoStream.FlushFinalBlock()

            Dim cipherBytes As Byte() = MStream.ToArray()
            MStream.Close()
            cryptoStream.Close()

            Return cipherBytes

        Catch ex As Exception

        End Try
        Return Encoding.UTF8.GetBytes("0")
    End Function