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，我收到一条错误消息，提示“要解密的数据长度无效”我正在获取要从文件中解密的字节数组。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给 Decrypt 方法，当我尝试使用加密流进行读取时，就会出现错误。

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

任何想法我做错了什么？

这里还有他们加密的代码：

        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

将您的文件流代码替换为 System.IO.File.ReadAllBytes、System.IO.File.WriteAllBytes。如果这可行，那么您就知道是文件流导致了问题。

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 之类的东西对其进行编码？尝试将其加密为字节数组，然后立即解密。如果它工作并成功解密，则说明存在编码问题。

Answer 3

这解决了它：

    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