/// <summary>/// 请求头解析/// </summary>public sealed class WebsocketHeaderInfo{    static byte[][] bytes = new byte[][] {            Encoding.ASCII.GetBytes("Connection: "),            Encoding.ASCII.GetBytes("Upgrade: "),            Encoding.ASCII.GetBytes("Origin: "),            Encoding.ASCII.GetBytes("Sec-WebSocket-Version: "),            Encoding.ASCII.GetBytes("Sec-WebSocket-Key: "),            Encoding.ASCII.GetBytes("Sec-WebSocket-Extensions: "),            Encoding.ASCII.GetBytes("Sec-WebSocket-Protocol: "),            Encoding.ASCII.GetBytes("Sec-WebSocket-Accept: "),        };    static byte[] httpBytes = Encoding.UTF8.GetBytes("HTTP/");    public HttpStatusCode StatusCode { get; set; } = HttpStatusCode.SwitchingProtocols;    public Memory<byte> Method { get; private set; }    private string _pathSet { get; set; }    /// <summary>    /// 用这个设置path值    /// </summary>    public string PathSet        {            get            {                return _pathSet;            }            set            {                _pathSet = value;                Path = Encoding.UTF8.GetBytes(_pathSet);            }        }    /// <summary>    /// 如果 仅1个字符，那就是 /    /// </summary>    public Memory<byte> Path { get; private set; }    public Memory<byte> Connection { get; private set; }    public Memory<byte> Upgrade { get; private set; }    public Memory<byte> Origin { get; private set; }    public Memory<byte> SecWebSocketVersion { get; private set; }    public Memory<byte> SecWebSocketKey { get; set; }    public Memory<byte> SecWebSocketExtensions { get; set; }    public Memory<byte> SecWebSocketProtocol { get; set; }    public Memory<byte> SecWebSocketAccept { get; set; }    public static WebsocketHeaderInfo Parse(Memory<byte> header)        {            Span<byte> span = header.Span;            int flag = 0xff;            int bit = 0x01;            ulong[] res = new ulong[bytes.Length];            for (int i = 0, len = span.Length; i < len; i++)            {                if (span[i] == 13 && span[i + 1] == 10 && span[i + 2] == 13 && span[i + 3] == 10)                {                    break;                }                if (span[i] == 13 && span[i + 1] == 10)                {                    int startIndex = i + 2;                    for (int k = 0; k < bytes.Length; k++)                    {                        if ((flag >> k & 1) == 1 && span[startIndex] == bytes[k][0])                        {                            if (span.Slice(startIndex, bytes[k].Length).SequenceEqual(bytes[k]))                            {                                int index = span.Slice(startIndex).IndexOf((byte)13);                                flag &= ~(bit << k);res[k] = ((ulong)(startIndex + bytes[k].Length) << 32) | (ulong)(index - bytes[k].Length);                                i += index + 1;                                break;                            }                        }                    }                }            }            WebsocketHeaderInfo headerInfo = new WebsocketHeaderInfo            {                Connection = header.Slice((int)(res[0] >> 32), (int)(res[0] & 0xffffffff)),                Upgrade = header.Slice((int)(res[1] >> 32), (int)(res[1] & 0xffffffff)),                Origin = header.Slice((int)(res[2] >> 32), (int)(res[2] & 0xffffffff)),                SecWebSocketVersion = header.Slice((int)(res[3] >> 32), (int)(res[3] & 0xffffffff)),                SecWebSocketKey = header.Slice((int)(res[4] >> 32), (int)(res[4] & 0xffffffff)),                SecWebSocketExtensions = header.Slice((int)(res[5] >> 32), (int)(res[5] & 0xffffffff)),                SecWebSocketProtocol = header.Slice((int)(res[6] >> 32), (int)(res[6] & 0xffffffff)),                SecWebSocketAccept = header.Slice((int)(res[7] >> 32), (int)(res[7] & 0xffffffff)),            };            int pathIndex = span.IndexOf((byte)32);            int pathIndex1 = span.Slice(pathIndex + 1).IndexOf((byte)32);            if (header.Slice(0, httpBytes.Length).Span.SequenceEqual(httpBytes))            {                string codeStr = Encoding.UTF8.GetString(header.Slice(pathIndex + 1, pathIndex1).Span);                int code = int.Parse(codeStr );                headerInfo.StatusCode = (HttpStatusCode)code;            }            else            {                headerInfo.Path = header.Slice(pathIndex + 1, pathIndex1);                headerInfo.Method = header.Slice(0, pathIndex);            }            return headerInfo;        }}

public sealed class WebSocketFrameRemarkInfo{    /// <summary>    /// 是否是结束帧，如果只有一帧，那必定是结束帧    /// </summary>    public WebSocketFrameInfo.EnumFin Fin { get; set; } = WebSocketFrameInfo.EnumFin.Fin;    /// <summary>    /// 保留位1    /// </summary>    public WebSocketFrameInfo.EnumRsv1 Rsv1 { get; set; } = WebSocketFrameInfo.EnumRsv1.None;    /// <summary>    /// 保留位2    /// </summary>    public WebSocketFrameInfo.EnumRsv2 Rsv2 { get; set; } = WebSocketFrameInfo.EnumRsv2.None;    /// <summary>    /// 保留位3    /// </summary>    public WebSocketFrameInfo.EnumRsv3 Rsv3 { get; set; } = WebSocketFrameInfo.EnumRsv3.None;    /// <summary>    /// 数据描述，默认TEXT数据    /// </summary>    public WebSocketFrameInfo.EnumOpcode Opcode { get; set; } = WebSocketFrameInfo.EnumOpcode.Text;    /// <summary>    /// 是否有掩码    /// </summary>    public WebSocketFrameInfo.EnumMask Mask { get; set; } = WebSocketFrameInfo.EnumMask.None;    /// <summary>    /// 掩码key 4字节    /// </summary>    public Memory<byte> MaskData { get; set; }    /// <summary>    /// payload data    /// </summary>    public Memory<byte> Data { get; set; }}/// <summary>/// 数据帧解析/// </summary>public sealed class WebSocketFrameInfo{    /// <summary>    /// 是否是结束帧    /// </summary>    public EnumFin Fin { get; set; }    /// <summary>    /// 保留位    /// </summary>    public EnumRsv1 Rsv1 { get; set; }    /// <summary>    ///     /// </summary>    public EnumRsv2 Rsv2 { get; set; }    /// <summary>    ///     /// </summary>    public EnumRsv3 Rsv3 { get; set; }    /// <summary>    /// 操作码 0附加数据，1文本，2二进制，3-7为非控制保留，8关闭，9ping，a pong，b-f 为控制保留    /// </summary>    public EnumOpcode Opcode { get; set; }    /// <summary>    /// 掩码    /// </summary>    public EnumMask Mask { get; set; }    /// <summary>    /// 总长度    /// </summary>    public int TotalLength { get; set; }    /// <summary>    /// 数据 如果OPCODE是 EnumOpcode.Close 则数据的前2字节为关闭状态码，余下的为其它描述数据    /// </summary>    public Memory<byte> PayloadData { get; set; }    /// <summary>    /// 解析帧，如果false解析失败，则应该把data缓存起来，等待下次来数据后，拼接起来再次解析    /// </summary>    /// <param name="data"></param>    /// <param name="frameInfo"></param>    /// <returns></returns>    public static bool TryParse(Memory<byte> data, out WebSocketFrameInfo frameInfo)        {            frameInfo = null;            //小于2字节不可解析            if (data.Length < 2)            {                return false;            }            Span<byte> span = data.Span;            int index = 2;            //第2字节            //1位 是否mask            EnumMask mask = (EnumMask)(span[1] & (byte)EnumMask.Mask);            int payloadLength = (span[1] & 0b01111111);            if (payloadLength == 126)            {                payloadLength = BinaryPrimitives.ReadUInt16BigEndian(span.Slice(2, 2));                index += 2;            }            else if (payloadLength == 127)            {                payloadLength = (int)BinaryPrimitives.ReadUInt64BigEndian(span.Slice(2, 8));                index += 8;            }            //数据长+头长 大于 整个数据长，则不是一个完整的包            if (data.Length < payloadLength + index + (mask == EnumMask.Mask ? 4 : 0))            {                return false;            }            //第1字节            //1位 是否是结束帧            EnumFin fin = (EnumFin)(byte)(span[0] & (byte)EnumFin.Fin);            //2 3 4 保留            EnumRsv1 rsv1 = (EnumRsv1)(byte)(span[0] & (byte)EnumRsv1.Rsv);            EnumRsv2 rsv2 = (EnumRsv2)(byte)(span[0] & (byte)EnumRsv2.Rsv);            EnumRsv3 rsv3 = (EnumRsv3)(byte)(span[0] & (byte)EnumRsv3.Rsv);            //5 6 7 8 操作码            EnumOpcode opcode = (EnumOpcode)(byte)(span[0] & (byte)EnumOpcode.Last);            Span<byte> maskKey = Helper.EmptyArray;            if (mask == EnumMask.Mask)            {                //mask掩码key 用来解码数据                maskKey = span.Slice(index, 4);                index += 4;            }            //数据            Memory<byte> payloadData = data.Slice(index, payloadLength);            if (mask == EnumMask.Mask)            {                //解码                Span<byte> payloadDataSpan = payloadData.Span;                for (int i = 0; i < payloadDataSpan.Length; i++)                {                    payloadDataSpan[i] = (byte)(payloadDataSpan[i] ^ maskKey[3 & i]);                }            }            frameInfo = new WebSocketFrameInfo            {                Fin = fin,                Rsv1 = rsv1,                Rsv2 = rsv2,                Rsv3 = rsv3,                Opcode = opcode,                Mask = mask,                PayloadData = payloadData,                TotalLength = index + payloadLength            };            return true;        }    public enum EnumFin : byte        {            None = 0x0,            Fin = 0b10000000,        }    public enum EnumMask : byte        {            None = 0x0,            Mask = 0b10000000,        }    public enum EnumRsv1 : byte        {            None = 0x0,            Rsv = 0b01000000,        }    public enum EnumRsv2 : byte        {            None = 0x0,            Rsv = 0b00100000,        }    public enum EnumRsv3 : byte        {            None = 0x0,            Rsv = 0b00010000,        }    public enum EnumOpcode : byte        {            Data = 0x0,            Text = 0x1,            Binary = 0x2,            UnControll3 = 0x3,            UnControll4 = 0x4,            UnControll5 = 0x5,            UnControll6 = 0x6,            UnControll7 = 0x7,            Close = 0x8,            Ping = 0x9,            Pong = 0xa,            Controll11 = 0xb,            Controll12 = 0xc,            Controll13 = 0xd,            Controll14 = 0xe,            Controll15 = 0xf,            Last = 0xf,        }    /// <summary>    /// 关闭的状态码    /// </summary>    public enum EnumCloseStatus : ushort        {            /// <summary>            /// 正常关闭            /// </summary>            Normal = 1000,            /// <summary>            /// 正在离开            /// </summary>            Leaving = 1001,            /// <summary>            /// 协议错误            /// </summary>            ProtocolError = 1002,            /// <summary>            /// 只能接收TEXT数据            /// </summary>            TextOnly = 1003,            /// <summary>            /// 保留            /// </summary>            None1004 = 1004,            /// <summary>            /// 保留            /// </summary>            None1005 = 1005,            /// <summary>            /// 保留            /// </summary>            None1006 = 1006,            /// <summary>            /// 消息类型不一致            /// </summary>            DataTypeError = 1007,            /// <summary>            /// 通用状态码，没有别的合适的状态码时，用这个            /// </summary>            PublicError = 1008,            /// <summary>            /// 数据太大，无法处理            /// </summary>            DataTooBig = 1009,            /// <summary>            /// 扩展错误            /// </summary>            ExtendsError = 1010,//正常关闭            /// <summary>            /// 意外情况            /// </summary>            Unexpected = 1011,            /// <summary>            /// TLS握手失败            /// </summary>            TLSError = 1015        }}

/// <summary>/// websocket解析器/// </summary>public static class WebSocketParser{    private readonly static SHA1 sha1 = SHA1.Create();    private readonly static Memory<byte> magicCode = Encoding.ASCII.GetBytes("258EAFA5-E914-47DA-95CA-C5AB0DC85B11");    /// <summary>    /// 构建连接数据    /// </summary>    /// <param name="header"></param>    /// <returns></returns>    public static byte[] BuildConnectData(WebsocketHeaderInfo header)        {            string path = header.Path.Length == 0 ? "/" : Encoding.UTF8.GetString(header.Path.Span);            StringBuilder sb = new StringBuilder(10);            sb.Append($"GET {path} HTTP/1.1\r\n");            sb.Append($"Upgrade: websocket\r\n");            sb.Append($"Connection: Upgrade\r\n");            sb.Append($"Sec-WebSocket-Version: 13\r\n");            sb.Append($"Sec-WebSocket-Key: {Encoding.UTF8.GetString(header.SecWebSocketKey.Span)}\r\n");            if (header.SecWebSocketProtocol.Length > 0)            {                sb.Append($"Sec-WebSocket-Protocol: {Encoding.UTF8.GetString(header.SecWebSocketProtocol.Span)}\r\n");            }            if (header.SecWebSocketExtensions.Length > 0)            {                sb.Append($"Sec-WebSocket-Extensions: {Encoding.UTF8.GetString(header.SecWebSocketExtensions.Span)}\r\n");            }            sb.Append("\r\n");            return Encoding.UTF8.GetBytes(sb.ToString());        }    /// <summary>    /// 构建连接回应数据    /// </summary>    /// <param name="header"></param>    /// <returns></returns>    public static byte[] BuildConnectResponseData(WebsocketHeaderInfo header)        {            string acceptStr = BuildSecWebSocketAccept(header.SecWebSocketKey);            StringBuilder sb = new StringBuilder(10);            sb.Append($"HTTP/1.1 {(int)header.StatusCode} {AddSpace(header.StatusCode)}\r\n");            sb.Append($"Sec-WebSocket-Accept: {acceptStr}\r\n");            if (header.Connection.Length > 0)            {                sb.Append($"Connection: {Encoding.UTF8.GetString(header.Connection.Span)}\r\n");            }            if (header.Upgrade.Length > 0)            {                sb.Append($"Upgrade: {Encoding.UTF8.GetString(header.Upgrade.Span)}\r\n");            }            if (header.SecWebSocketVersion.Length > 0)            {                sb.Append($"Sec-WebSocket-Version: {Encoding.UTF8.GetString(header.SecWebSocketVersion.Span)}\r\n");            }            if (header.SecWebSocketProtocol.Length > 0)            {                sb.Append($"Sec-WebSocket-Protocol: {Encoding.UTF8.GetString(header.SecWebSocketProtocol.Span)}\r\n");            }            if (header.SecWebSocketExtensions.Length > 0)            {                sb.Append($"Sec-WebSocket-Extensions: {Encoding.UTF8.GetString(header.SecWebSocketExtensions.Span)}\r\n");            }            sb.Append("\r\n");            return Encoding.UTF8.GetBytes(sb.ToString());        }    /// <summary>    /// 生成随机key    /// </summary>    /// <returns></returns>    public static byte[] BuildSecWebSocketKey()        {            byte[] bytes = new byte[16];            Random random = new Random(DateTime.Now.Ticks.GetHashCode());            for (int i = 0; i < bytes.Length; i++)            {                bytes[i] = (byte)random.Next(0, 255);            }            byte[] res = Encoding.UTF8.GetBytes(Convert.ToBase64String(bytes));            return res;        }    /// <summary>    /// 构建mask数据    /// </summary>    /// <returns></returns>    public static byte[] BuildMaskKey()        {            byte[] bytes = new byte[4];            Random random = new Random(DateTime.Now.Ticks.GetHashCode());            for (int i = 0; i < bytes.Length; i++)            {                bytes[i] = (byte)random.Next(0, 255);            }            return bytes;        }    /// <summary>    /// 生成accept回应    /// </summary>    /// <param name="key"></param>    /// <returns></returns>    private static string BuildSecWebSocketAccept(Memory<byte> key)        {            int keyLength = key.Length + magicCode.Length;            byte[] acceptBytes = new byte[keyLength];            key.CopyTo(acceptBytes);            magicCode.CopyTo(acceptBytes.AsMemory(key.Length));            string acceptStr = Convert.ToBase64String(sha1.ComputeHash(acceptBytes, 0, keyLength));            return acceptStr;        }    /// <summary>    /// 验证回应的accept    /// </summary>    /// <param name="key"></param>    /// <param name="accept"></param>    /// <returns></returns>    public static bool VerifySecWebSocketAccept(Memory<byte> key, Memory<byte> accept)        {            string acceptStr = BuildSecWebSocketAccept(key);            return acceptStr == Encoding.UTF8.GetString(accept.Span);        }    /// <summary>    /// 构建ping帧    /// </summary>    /// <returns></returns>    public static byte[] BuildPingData()        {            return new byte[]            {                (byte)WebSocketFrameInfo.EnumFin.Fin | (byte)WebSocketFrameInfo.EnumOpcode.Ping, //fin + ping                (byte)WebSocketFrameInfo.EnumMask.None | 0, //没有 mask 和 payload length            };        }    /// <summary>    /// 构建pong帧    /// </summary>    /// <returns></returns>    public static byte[] BuildPongData()        {            return new byte[]            {                (byte)WebSocketFrameInfo.EnumFin.Fin | (byte)WebSocketFrameInfo.EnumOpcode.Pong, //fin + pong                (byte)WebSocketFrameInfo.EnumMask.None | 0, //没有 mask 和 payload length            };        }    /// <summary>    /// 构建数据帧    /// </summary>    /// <param name="remark"></param>    /// <returns></returns>    /// <exception cref="Exception"></exception>    public static byte[] BuildFrameData(WebSocketFrameRemarkInfo remark)        {            if (remark.Mask > 0 && remark.MaskData.Length != 4)            {                throw new Exception("mask data just 4byte");            }            int length = 1 + 1 + remark.Data.Length, index = 2;            if (remark.Mask == WebSocketFrameInfo.EnumMask.Mask)            {                length += 4;            }            byte payloadLength;            int dataLength = remark.Data.Length;            if (dataLength > ushort.MaxValue)            {                length += 8;                payloadLength = 127;            }            else if (dataLength > 125)            {                length += 2;                payloadLength = 126;            }            else            {                payloadLength = (byte)dataLength;            }            byte[] bytes = new byte[length];            var memory = bytes.AsMemory();            bytes[0] = (byte)((byte)remark.Fin | (byte)remark.Rsv1 | (byte)remark.Rsv2 | (byte)remark.Rsv3 | (byte)remark.Opcode);            bytes[1] = (byte)((byte)remark.Mask | payloadLength);            if (dataLength > ushort.MaxValue)            {                BinaryPrimitives.WriteUInt64BigEndian(memory.Slice(index).Span, (ulong)dataLength);                index += 8;            }            else if (dataLength > 125)            {                BinaryPrimitives.WriteUInt16BigEndian(memory.Slice(index).Span, (ushort)dataLength);                index += 2;            }            if (remark.Mask == WebSocketFrameInfo.EnumMask.Mask)            {                remark.MaskData.CopyTo(bytes.AsMemory(index, remark.MaskData.Length));                index += remark.MaskData.Length;            }            if (remark.Data.Length > 0)            {                remark.Data.CopyTo(bytes.AsMemory(index));            }            return bytes;        }    /// <summary>    /// 给每个大写字母前加一个空格，例如ProxyAuthenticationRequired 变成Proxy Authentication Required    /// </summary>    /// <param name="statusCode"></param>    /// <returns></returns>    private static string AddSpace(HttpStatusCode statusCode)        {            ReadOnlySpan<char> span = statusCode.ToString().AsSpan();            int totalLength = span.Length * 2;            char[] result = new char[totalLength];            Span<char> resultSpan = result.AsSpan(0, totalLength);            span.CopyTo(resultSpan);            int length = 0;            for (int i = 0; i < span.Length; i++)            {                if (i > 0 && span[i] >= 65 && span[i] <= 90)                {                    resultSpan.Slice(i + length, totalLength - (length + i) - 1).CopyTo(resultSpan.Slice(i + length + 1));                    resultSpan[i + length] = (char)32;                    length++;                }            }            string resultStr = resultSpan.Slice(0, span.Length + length).ToString();            return resultStr;        }}