chocoboba

public byte[] HybiEncode(string message)
{
    if (message.Length > 125)
    {
        message = message.Substring(0, 125);
    }

    byte[] payload = Encoding.UTF8.GetBytes(message);
    List<int> frameHead = new List<int>();
    int payloadLength = payload.Length;

chocoboba

string line = ClientHandshakeLines.FirstOrDefault(l => l.Contains("Sec-WebSocket-Key:"));
if (!string.IsNullOrEmpty(line))
{
    Handshake = "HTTP/1.1 101 Switching Protocols" + Environment.NewLine;
    Handshake += "Upgrade: websocket" + Environment.NewLine;
    Handshake += "Connection: Upgrade" + Environment.NewLine;
    Handshake += "Sec-WebSocket-Accept: "; 
    Handshake += ComputeWebSocketHandshakeSecurityHash09(line.Substring(line.IndexOf(":") + 2));
    Handshake += Environment.NewLine;
    Handshake += Environment.NewLine;

chocoboba

public string HybiDecode(byte[] data)
{
    byte firstByte = data[0];
    byte secondByte = data[1];
    int opcode = firstByte & 0x0F;
    bool isMasked = ((firstByte & 128) == 128);
    int payloadLength = secondByte & 0x7F;

    if (!isMasked) { return null; } // not masked
    if (opcode != 1) { return null; } // not text

chocoboba

public String ComputeWebSocketHandshakeSecurityHash09(String secWebSocketKey)
{
    const String MagicKEY = "258EAFA5-E914-47DA-95CA-C5AB0DC85B11";
    String secWebSocketAccept = String.Empty;

    // 1. Combine the request Sec-WebSocket-Key with magic key.
    String ret = secWebSocketKey + MagicKEY;

    // 2. Compute the SHA1 hash
    SHA1 sha = new SHA1CryptoServiceProvider();