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NetworkStream.Write - Malformed Packet

I am attempting to send a very simple packet of data over a TCP connection. My server never received the packet, so I connected Wireshark to see what was happening. Wireshark is reporting it as a "Malformed Packet" (packet 1625 of attached capture). I do not understand what is wrong with the data I am sending (or how I'm sending it).

tcpClient = new TcpClient(ipAddress, PORTNUMBER);
netStream = tcpClient.GetStream();

BinaryWriter packet = new BinaryWriter(new MemoryStream(sendBuffer));

packet.Write((uint)BodyType.cmd_GETCALIBPOS);
packet.Write((uint)8);

packet.Write((uint)data1);
packet.Write((uint)data2);

netStream.Write(sendBuffer, 0, 16);

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SOLUTION

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ASKER

I have verified in the debugger that my "sendBuffer" does in fact have the data populated.

The reason I'm using NetworkStream is because the TcpClient class does not expose the "send" method. It only allows access to the NetworkStream. Read/Writing must be done on the stream.

ASKER CERTIFIED SOLUTION

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You can examine NetworkStream with Reflector:

Public Overrides Sub Write(ByVal buffer As Byte(), ByVal offset As Integer, ByVal size As Integer)
....
streamSocket.Send(buffer, offset, size, SocketFlags.None)

Then NetworkStream on Output is full transparent from StreamSocket.

Public Overrides Sub Write(ByVal buffer As Byte(), ByVal offset As Integer, ByVal size As Integer)
    If Me.m_CleanedUp Then
        Throw New ObjectDisposedException(MyBase.GetType.FullName)
    End If
    If (buffer Is Nothing) Then
        Throw New ArgumentNullException("buffer")
    End If
    If ((offset < 0) OrElse (offset > buffer.Length)) Then
        Throw New ArgumentOutOfRangeException("offset")
    End If
    If ((size < 0) OrElse (size > (buffer.Length - offset))) Then
        Throw New ArgumentOutOfRangeException("size")
    End If
    If Not Me.CanWrite Then
        Throw New InvalidOperationException(SR.GetString("net_readonlystream"))
    End If
    Dim streamSocket As Socket = Me.m_StreamSocket
    If (streamSocket Is Nothing) Then
        Throw New IOException(SR.GetString("net_io_writefailure", New Object() { SR.GetString("net_io_connectionclosed") }))
    End If
    Try 
        streamSocket.Send(buffer, offset, size, SocketFlags.None)
    Catch exception As Exception
        If ((TypeOf exception Is ThreadAbortException OrElse TypeOf exception Is StackOverflowException) OrElse TypeOf exception Is OutOfMemoryException) Then
            Throw
        End If
        Throw New IOException(SR.GetString("net_io_writefailure", New Object() { exception.Message }), exception)
    Catch obj1 As Object
        Throw New IOException(SR.GetString("net_io_writefailure", New Object() { String.Empty }), New Exception(SR.GetString("net_nonClsCompliantException")))
    End Try
End Sub

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ASKER

Changed my implementation to use the Socket class instead of the TcpClient class. Now it's working fine.

Thanks!