sockscape/server/Libraries/Kneesocks/Connection.cs
2017-09-12 15:59:55 -05:00

356 lines
12 KiB
C#

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net.Sockets;
using System.Text;
using System.Threading.Tasks;
using Glove;
using System.IO;
using System.Net;
namespace Kneesocks {
public class Connection {
private bool Initialized = false;
private UInt64? _Id = null;
public UInt64 Id {
get {
if(_Id == null)
throw new ArgumentNullException();
return (UInt64)_Id;
}
set {
if(_Id == null)
_Id = value;
}
}
internal bool IsIdNull
=> _Id == null;
private TcpClient Socket = null;
private NetworkStream Stream = null;
public Server Server { get; internal set; }
ReadBuffer Buffer;
private byte[] FirstTwoBytes = null;
private int ExtraHeaderSize = 0;
private byte[] FrameHeader = null;
private List<Frame> ReceiveFrameBuffer = new List<Frame>();
private List<Frame> SendFrameBuffer = new List<Frame>();
private const int MaximumSendFrameSize = 0xFFFFF;
protected const int PingInterval = 30;
protected const int TimeoutInterval = 120;
private readonly byte[] PingData = Encoding.ASCII.GetBytes("woomy!");
private DateTime LastPing;
private bool AwaitingPingResponse = false;
private TimeSpan TimeSinceLastPing
=> DateTime.UtcNow - LastPing;
internal bool OutsidePool = false;
public bool Disconnected { get; private set; } = false;
public string DisconnectReason { get; private set; } = null;
public bool Handshaked { get; private set; } = false;
public Handshake ClientHandshake { get; private set; } = null;
public IPAddress IP
=> ((IPEndPoint)Socket.Client.RemoteEndPoint).Address;
public void Initialize(TcpClient sock) {
if(Initialized)
return;
Socket = sock;
Socket.ReceiveTimeout = 1;
Stream = sock.GetStream();
Buffer = new ReadBuffer(Stream);
Initialized = true;
}
public void Initialize(UInt64 id, TcpClient sock) {
if(Initialized)
return;
Initialize(sock);
Id = id;
Initialized = true;
}
public void Initialize(Connection conn, bool preserveId = false) {
if(Initialized)
return;
if(preserveId)
_Id = conn._Id;
Socket = conn.Socket;
Stream = conn.Stream;
Server = conn.Server;
Buffer = conn.Buffer;
FirstTwoBytes = conn.FirstTwoBytes;
ExtraHeaderSize = conn.ExtraHeaderSize;
FrameHeader = conn.FrameHeader;
ReceiveFrameBuffer = conn.ReceiveFrameBuffer;
LastPing = conn.LastPing;
Disconnected = conn.Disconnected;
DisconnectReason = conn.DisconnectReason;
Handshaked = conn.Handshaked;
ClientHandshake = conn.ClientHandshake;
Initialized = true;
}
private void _Send(byte[] message, bool isFinal = true, bool singleFrame = false, bool first = false) {
int frameCount = singleFrame ? 0 : (message.Length / MaximumSendFrameSize);
for(var i = 0; i <= frameCount; ++i) {
SendFrameBuffer.Add(new Frame {
IsFinal = (i == frameCount && isFinal),
IsMasked = false,
Opcode = (i == 0 || (singleFrame && first)) ? Frame.kOpcode.BinaryFrame : Frame.kOpcode.Continuation,
Content = message.Subset(i * (MaximumSendFrameSize + 1), MaximumSendFrameSize)
});
}
}
public void Send(byte[] message) {
lock(SendFrameBuffer) {
_Send(message);
}
}
private void _Send(Stream stream, bool startingFrame = true) {
if(!Socket.Connected)
return;
bool firstRead = true;
byte[] byteBuffer = new byte[MaximumSendFrameSize];
while(true) {
var bytesRead = stream.Read(byteBuffer, 0, MaximumSendFrameSize);
if(stream.Position == stream.Length) {
_Send(bytesRead == MaximumSendFrameSize ? byteBuffer : byteBuffer.Take(bytesRead).ToArray(), true, true, firstRead);
return;
}
_Send(bytesRead == MaximumSendFrameSize ? byteBuffer : byteBuffer.Take(bytesRead).ToArray(), false, true, firstRead);
firstRead = false;
}
}
public void Send(Stream stream) {
lock(SendFrameBuffer) {
_Send(stream);
}
}
public void Send(byte[] preamble, Stream stream) {
lock(SendFrameBuffer) {
_Send(preamble, false);
_Send(stream, false);
}
}
private void ReadIfNotNull(ref byte[] buffer, int length) {
buffer = buffer ?? Buffer.AttemptRead(length)
;
}
private void ReadIfNotNull(ref byte[] buffer, string terminator) {
buffer = buffer ?? Buffer.AttemptRead(terminator)
;
}
internal void Parse() {
if(Handshaked) {
if(!Buffer.IsReading) {
if(TimeSinceLastPing.TotalSeconds > TimeoutInterval) {
Disconnect(Frame.kClosingReason.Normal, "Ping response timed out.");
} else if(TimeSinceLastPing.TotalSeconds > PingInterval && !AwaitingPingResponse) {
var frameBytes = new Frame {
IsFinal = true,
IsMasked = false,
Opcode = Frame.kOpcode.Ping,
Content = PingData
}.GetBytes();
Stream.Write(frameBytes, 0, frameBytes.Length);
AwaitingPingResponse = true;
}
}
lock(SendFrameBuffer) {
if(SendFrameBuffer.Count > 0) {
foreach(var frame in SendFrameBuffer) {
var frameBytes = frame.GetBytes();
Stream.Write(frameBytes, 0, frameBytes.Length);
}
SendFrameBuffer = new List<Frame>();
}
}
}
OnParse();
byte[] readBuffer = null;
if(Buffer.IsReading) {
readBuffer = Buffer.AttemptRead();
if(readBuffer == null) {
if((!Handshaked || (Handshaked && FirstTwoBytes != null)) && Buffer.ElapsedReadTime.TotalSeconds > (Handshaked ? 300 : 30))
Disconnect(Frame.kClosingReason.ProtocolError, "Timed out waiting for a full response");
return;
}
}
if(!Handshaked) {
ReadIfNotNull(ref readBuffer, "\r\n\r\n");
if(readBuffer == null)
return;
try {
Handshake request = new Handshake(Encoding.ASCII.GetString(readBuffer));
var response = Handshake.AcceptRequest(request).ToBytes();
Stream.Write(response, 0, response.Length);
ClientHandshake = request;
Handshaked = true;
LastPing = DateTime.UtcNow;
} catch(Exception e) {
Disconnect(Frame.kClosingReason.ProtocolError, e.Message);
return;
}
OnOpen();
return;
}
if(FirstTwoBytes == null) {
ReadIfNotNull(ref readBuffer, 2);
if(readBuffer == null)
return;
FirstTwoBytes = readBuffer;
ExtraHeaderSize = Frame.HeaderLengthFromBytes(FirstTwoBytes) - 2;
readBuffer = null;
}
if(FrameHeader == null) {
if(ExtraHeaderSize == 0)
FrameHeader = FirstTwoBytes;
else {
ReadIfNotNull(ref readBuffer, ExtraHeaderSize);
if(readBuffer == null)
return;
FrameHeader = FirstTwoBytes.Concat(readBuffer).ToArray();
}
readBuffer = null;
}
if(FrameHeader != null) {
Frame tempFrame;
if(readBuffer == null) {
try {
tempFrame = Frame.HeaderFromBytes(FrameHeader);
} catch(Exception e) {
Disconnect(Frame.kClosingReason.ProtocolError, e.Message);
return;
}
readBuffer = Buffer.AttemptRead(tempFrame.BodyLength);
if(readBuffer == null)
return;
}
try {
tempFrame = Frame.FromBytes(FrameHeader.Concat(readBuffer).ToArray());
} catch(Exception e) {
Disconnect(Frame.kClosingReason.ProtocolError, e.Message);
return;
}
ReceiveFrameBuffer.Add(tempFrame);
FirstTwoBytes = null;
ExtraHeaderSize = 0;
FrameHeader = null;
if(tempFrame.IsFinal) {
switch(tempFrame.Opcode) {
case Frame.kOpcode.Ping:
LastPing = DateTime.UtcNow;
AwaitingPingResponse = false;
tempFrame.Opcode = Frame.kOpcode.Pong;
var pingBuffer = tempFrame.GetBytes();
Stream.Write(pingBuffer, 0, pingBuffer.Length);
break;
case Frame.kOpcode.Pong:
LastPing = DateTime.UtcNow;
AwaitingPingResponse = false;
break;
case Frame.kOpcode.Close:
Disconnect(Frame.kClosingReason.Normal, "Connection closed.");
break;
case Frame.kOpcode.BinaryFrame:
case Frame.kOpcode.TextFrame:
case Frame.kOpcode.Continuation:
byte[] byteBuffer = new byte[0];
foreach(var frame in ReceiveFrameBuffer)
byteBuffer = byteBuffer.Concat(frame.Content).ToArray();
ReceiveFrameBuffer = new List<Frame>();
OnReceive(byteBuffer);
break;
}
}
}
}
public void RemoveFromPool() => OutsidePool = true;
public void Disconnect(string reason = null) => Disconnect(Frame.kClosingReason.Normal, reason);
public void Disconnect(Frame.kClosingReason status, string reason = null) {
Disconnected = true;
DisconnectReason = reason;
if(Socket.Connected) {
Socket.SendTimeout = 1000;
var raw = Handshaked ? Frame.Closing(status, reason).GetBytes()
: Handshake.DenyRequest(message: reason).ToString().GetBytes();
Stream.Write(raw, 0, raw.Length);
Socket.Close();
}
OnClose();
}
// called after the client successfully handshakes
protected virtual void OnOpen() { }
// called when the thread manager iterates through
// the thread list and stops on this thread
protected virtual void OnParse() { }
// called when data has been received
protected virtual void OnReceive(byte[] data) { }
// called when the connection is disconnected
protected virtual void OnClose() { }
}
}