Question

我尝试通过Websocket创建和应用。当我尝试向客户端客户端发送任何消息关闭连接时，我做了握手，因为WebSocket错误：网络错误12152

我猜问题是编码数据。我使用了基于Websocket new frame byte

的脚本

但它不能正常工作。我希望你能帮帮我这是我的代码：

Dim rawData = System.Text.Encoding.UTF8.GetBytes("hello")
                Dim frameCount = 0
                Dim frame(10) As Byte
                frame(0) = CByte(129)

                If rawData.Length <= 125 Then
                    frame(1) = CByte(rawData.Length + 1)
                    frameCount = 2
                ElseIf rawData.Length >= 126 AndAlso rawData.Length <= 65535 Then
                    frame(1) = CByte(126)
                    Dim len = CByte(rawData.Length)
                    frame(2) = CByte(((len >> 8) & CByte(255)))
                    frame(3) = CByte((len & CByte(255)))
                    frameCount = 4
                Else
                    frame(1) = CByte(127)
                    Dim len = CByte(rawData.Length)
                    frame(2) = CByte(((len >> 56) & CByte(255)))
                    frame(3) = CByte(((len >> 48) & CByte(255)))
                    frame(4) = CByte(((len >> 40) & CByte(255)))
                    frame(5) = CByte(((len >> 32) & CByte(255)))
                    frame(6) = CByte(((len >> 24) & CByte(255)))
                    frame(7) = CByte(((len >> 16) & CByte(255)))
                    frame(8) = CByte(((len >> 8) & CByte(255)))
                    frame(9) = CByte((len & CByte(255)))
                    frameCount = 10
                End If
                Dim bLength = frameCount + rawData.Length
                'Console.WriteLine(frameCount)
                'Console.WriteLine(rawData.Length)
                Dim reply(bLength) As Byte

                Dim bLim = 0
                For i = 0 To frameCount - 1
                    'Console.WriteLine(bLim)
                    reply(bLim) = frame(i)
                    bLim += 1
                Next

                For i = 0 To rawData.Length - 1
                    'Console.WriteLine(bLim)
                    reply(bLim) = rawData(i)
                    bLim += 1
                Next
                For i = 0 To reply.Length - 1
                    'Console.WriteLine("Byte: " & reply(i))
                    'Console.WriteLine("Char: " & CByte(reply(i)))
                Next

                Dim asd As String = Encoding.UTF8.GetString(reply)
                Console.WriteLine(asd)
                pv_streamwriter.WriteLine(asd)
                pv_streamwriter.Flush()

Answer 1

感谢您使用我的代码。绝对酷看。

无论如何，我自己发现了发送功能这个烦人的问题。

根据RFC6455您必需在向服务器发送消息时屏蔽已发送的消息，但在将消息从服务器发送到客户端时不需要屏蔽消息。现在，我已经说过，我已经改变了这个功能，包括从客户端到服务器的屏蔽。我将删除我的特定掩码，因为我不想在网上。希望这会有所帮助。

关于创建安全掩码的说明。 RFC6455提到了RFC4086：

The masking key is a 32-bit value chosen at random by the client.
   When preparing a masked frame, the client MUST pick a fresh masking
   key from the set of allowed 32-bit values.  The masking key needs to
   be unpredictable; thus, the masking key MUST be derived from a strong
   source of entropy, and the masking key for a given frame MUST NOT
   make it simple for a server/proxy to predict the masking key for a
   subsequent frame.  The unpredictability of the masking key is
   essential to prevent authors of malicious applications from selecting
   the bytes that appear on the wire.  [RFC 4086][RFC4086] discusses what
   entails a suitable source of entropy for security-sensitive
   applications.

老实说，我只是想在我遵循该文档之前让它工作，所以我使用了Rnd()，模数和其他一些东西的组合来使其难以解码。

Sub SendMessage2(ByVal socket As Socket, ByVal message As String, ByVal len As Integer)
    Dim frameCount As Integer
    Dim len16 As UInt16
    Dim reply(len + 8) As [Byte]
    Dim frame(10) As [Byte]
    Dim maskingBytes(4) As [Byte]

    frame(0) = CByte(&H81)

    If (len <= 125) Then
        frame(1) = CByte(len + 128)
        frameCount = 2
    ElseIf (len >= 126 AndAlso len <= 65535) Then
        frame(1) = CByte(126 + 128)
        len16 = Convert.ToUInt16(len)
        frame(2) = CByte(BitConverter.GetBytes(len16).GetValue(0))
        frame(3) = CByte(BitConverter.GetBytes(len16).GetValue(1))
        frameCount = 4
    Else
        frame(1) = CByte(127 + 128)
        'Odds are we are not ever going to get here. but here is some code
        'frame(2) = CByte(((len >> 56) And CByte(255)))
        'frame(3) = CByte(((len >> 48) And CByte(255)))
        'frame(4) = CByte(((len >> 40) And CByte(255)))
        'frame(5) = CByte(((len >> 32) And CByte(255)))
        'frame(6) = CByte(((len >> 24) And CByte(255)))
        'frame(7) = CByte(((len >> 16) And CByte(255)))
        'frame(8) = CByte(((len >> 8) And CByte(255)))
        'frame(9) = CByte((len) And CByte(255))
        frameCount = 10
    End If

    For i As Integer = 0 To frameCount - 1
        reply(i) = Convert.ToByte(frame(i))
    Next

    For i As Integer = 0 To 3
        Randomize()
        maskingBytes(i) = 0'This is where you need to create your own masking byte
        reply(frameCount + i) = maskingBytes(i)
    Next

    For i As Integer = 0 To len
        If (Not i = len) Then
            reply(frameCount + i + 4) = Convert.ToByte(message.Chars(i)) Xor maskingBytes(i Mod 4)
        Else
            reply(frameCount + i + 4) = CByte(0) Xor maskingBytes(i Mod 4)
        End If
    Next


    If (socket.Send(reply) <= 0) Then
        Console.WriteLine("WE ARE NOT WRITING!!")
    End If

End Sub

VB套接字服务器和Websocket客户端数据发送

1 个答案: