string ReadToEndForHandshake(Stream stream)
{
using (ArrayBuffer readBuffer = bufferPool.Take(maxHttpHeaderSize))
{
int?readCountOrFail = ReadHelper.SafeReadTillMatch(stream, readBuffer.array, 0, maxHttpHeaderSize, Constants.endOfHandshake);
if (!readCountOrFail.HasValue)
{
return(null);
}
int readCount = readCountOrFail.Value;
string msg = Encoding.ASCII.GetString(readBuffer.array, 0, readCount);
Log.Verbose(msg);
return(msg);
}
}
public bool TryHandshake(Connection conn)
{
Stream stream = conn.stream;
using (ArrayBuffer getHeader = bufferPool.Take(GetSize))
{
if (!ReadHelper.TryRead(stream, getHeader.array, 0, GetSize))
{
return(false);
}
getHeader.count = GetSize;
if (!IsGet(getHeader.array))
{
Log.Warn($"First bytes from client was not 'GET' for handshake, instead was {Log.BufferToString(getHeader.array, 0, GetSize)}");
return(false);
}
}
string msg = ReadToEndForHandshake(stream);
if (string.IsNullOrEmpty(msg))
{
return(false);
}
try
{
AcceptHandshake(stream, msg);
return(true);
}
catch (ArgumentException e)
{
Log.InfoException(e);
return(false);
}
}
static Header ReadHeader(Config config, byte[] buffer, bool opCodeContinuation = false)
{
(Connection conn, int maxMessageSize, bool expectMask, ConcurrentQueue <Message> queue, BufferPool bufferPool) = config;
Stream stream = conn.stream;
var header = new Header();
// read 2
header.offset = ReadHelper.Read(stream, buffer, header.offset, Constants.HeaderMinSize);
// log after first blocking call
Log.Verbose($"Message From {conn}");
if (MessageProcessor.NeedToReadShortLength(buffer))
{
header.offset = ReadHelper.Read(stream, buffer, header.offset, Constants.ShortLength);
}
if (MessageProcessor.NeedToReadLongLength(buffer))
{
header.offset = ReadHelper.Read(stream, buffer, header.offset, Constants.LongLength);
}
Log.DumpBuffer($"Raw Header", buffer, 0, header.offset);
MessageProcessor.ValidateHeader(buffer, maxMessageSize, expectMask, opCodeContinuation);
if (expectMask)
{
header.offset = ReadHelper.Read(stream, buffer, header.offset, Constants.MaskSize);
}
header.opcode = MessageProcessor.GetOpcode(buffer);
header.payloadLength = MessageProcessor.GetPayloadLength(buffer);
header.finished = MessageProcessor.Finished(buffer);
Log.Verbose($"Header ln:{header.payloadLength} op:{header.opcode} mask:{expectMask}");
return(header);
}
static void ReadOneMessage(Config config, byte[] buffer)
{
(Connection conn, int maxMessageSize, bool expectMask, ConcurrentQueue <Message> queue, BufferPool bufferPool) = config;
Stream stream = conn.stream;
Header header = ReadHeader(config, buffer);
int msgOffset = header.offset;
header.offset = ReadHelper.Read(stream, buffer, header.offset, header.payloadLength);
if (header.finished)
{
switch (header.opcode)
{
case 2:
HandleArrayMessage(config, buffer, msgOffset, header.payloadLength);
break;
case 8:
HandleCloseMessage(config, buffer, msgOffset, header.payloadLength);
break;
}
}
else
{
// todo cache this to avoid allocations
var fragments = new Queue <ArrayBuffer>();
fragments.Enqueue(CopyMessageToBuffer(bufferPool, expectMask, buffer, msgOffset, header.payloadLength));
int totalSize = header.payloadLength;
while (!header.finished)
{
header = ReadHeader(config, buffer, opCodeContinuation: true);
msgOffset = header.offset;
header.offset = ReadHelper.Read(stream, buffer, header.offset, header.payloadLength);
fragments.Enqueue(CopyMessageToBuffer(bufferPool, expectMask, buffer, msgOffset, header.payloadLength));
totalSize += header.payloadLength;
MessageProcessor.ThrowIfMsgLengthTooLong(totalSize, maxMessageSize);
}
ArrayBuffer msg = bufferPool.Take(totalSize);
msg.count = 0;
while (fragments.Count > 0)
{
ArrayBuffer part = fragments.Dequeue();
part.CopyTo(msg.array, msg.count);
msg.count += part.count;
part.Release();
}
// dump after mask off
Log.DumpBuffer($"Message", msg);
queue.Enqueue(new Message(conn.connId, msg));
}
}
public bool TryHandshake(Connection conn, Uri uri)
{
try
{
Stream stream = conn.stream;
byte[] keyBuffer = new byte[16];
using (var rng = new RNGCryptoServiceProvider())
{
rng.GetBytes(keyBuffer);
}
string key = Convert.ToBase64String(keyBuffer);
string keySum = key + Constants.HandshakeGUID;
byte[] keySumBytes = Encoding.ASCII.GetBytes(keySum);
Log.Verbose($"Handshake Hashing {Encoding.ASCII.GetString(keySumBytes)}");
byte[] keySumHash = SHA1.Create().ComputeHash(keySumBytes);
string expectedResponse = Convert.ToBase64String(keySumHash);
string handshake =
$"GET {uri.PathAndQuery} HTTP/1.1\r\n" +
$"Host: {uri.Host}:{uri.Port}\r\n" +
$"Upgrade: websocket\r\n" +
$"Connection: Upgrade\r\n" +
$"Sec-WebSocket-Key: {key}\r\n" +
$"Sec-WebSocket-Version: 13\r\n" +
"\r\n";
byte[] encoded = Encoding.ASCII.GetBytes(handshake);
stream.Write(encoded, 0, encoded.Length);
byte[] responseBuffer = new byte[1000];
int?lengthOrNull = ReadHelper.SafeReadTillMatch(stream, responseBuffer, 0, responseBuffer.Length, Constants.endOfHandshake);
if (!lengthOrNull.HasValue)
{
Log.Error("Connected closed before handshake");
return(false);
}
string responseString = Encoding.ASCII.GetString(responseBuffer, 0, lengthOrNull.Value);
string acceptHeader = "Sec-WebSocket-Accept: ";
int startIndex = responseString.IndexOf(acceptHeader, StringComparison.InvariantCultureIgnoreCase) + acceptHeader.Length;
int endIndex = responseString.IndexOf("\r\n", startIndex);
string responseKey = responseString.Substring(startIndex, endIndex - startIndex);
if (responseKey != expectedResponse)
{
Log.Error($"Response key incorrect, Response:{responseKey} Expected:{expectedResponse}");
return(false);
}
return(true);
}
catch (Exception e)
{
Log.Exception(e);
return(false);
}
}