private byte[] MintToken(QuicheHeaderInfo header, IPEndPoint src)
{
var token = Encoding.ASCII.GetBytes("quiche");
var addr = src.Address.GetAddressBytes();
return(token.Concat(addr).Concat(header.Dcid).ToArray());
}
private void Poll(ClientState state)
{
var recvBytes = state.ReceiveBytes;
var remoteIpEndPoint = state.remoteIpEndPoint;
QuicheHeaderInfo header;
try{
header = QuicheHeaderInfo.Construct(recvBytes);
} catch (Exception e)
{
Debug.LogError($"{e}");
return;
}
if (header.Type == 6 /* Type::VersionNegotiation */)
{
Debug.LogError("Version negotiation invalid on the server");
return;
}
var key = HexDump(header.Dcid);
Client client;
if (!clients.TryGetValue(key, out client))
{
if (header.Type != 1 /* Type::Initial */)
{
Debug.LogError("Packet is not Initial");
return;
}
if (!VersionIsSupported(header.Version))
{
Debug.LogWarning("Doing version negotiation");
var length = (int)NegotiateVersion(
header.Scid, header.Dcid, negotiateBuf);
var sendBuf = negotiateBuf.Take(length).ToArray();
udpClient.Send(sendBuf, length, remoteIpEndPoint);
return;
}
var scid = new byte[QuicheClient.LOCAL_CONN_ID_LEN];
new System.Random().NextBytes(scid);
byte[] odcid = new byte[65535];
if (!noRetry)
{
if (header.Token.Length == 0)
{
Debug.LogWarning("Doing stateless retry");
Debug.Log($"Retry: scid={HexDump(header.Scid)} new_scid={HexDump(scid)}");
var new_token = MintToken(header, remoteIpEndPoint);
var _out = new byte[65535];
var written = (int)Retry(header.Scid, header.Dcid, scid, new_token, _out);
udpClient.Send(
_out.Take(written).ToArray(), written, remoteIpEndPoint);
return;
}
odcid = ValidateToken(header.Token, remoteIpEndPoint);
if (odcid == null)
{
Debug.LogError("Invalid address validation token");
return;
}
}
if (scid.Length != header.Dcid.Length)
{
Debug.LogError("Invalid destination connection ID");
return;
}
scid = header.Dcid;
var conn = quiche.Accept(scid, odcid);
var _client = new Client(conn, remoteIpEndPoint);
clients.Add(HexDump(scid), _client);
client = _client;
}
var read = client.Connection.Receive(recvBytes);
if (read == (int)QuicheError.QUICHE_ERR_DONE)
{
Debug.Log("done reading");
return;
}
if (read < 0)
{
QuicheError err = (QuicheError)Enum
.ToObject(typeof(QuicheError), read);
Debug.LogError($"recv failed {err}");
throw new Exception();
}
Debug.Log($"recv {read} bytes");
if (client.Connection.IsInEarlyData || client.Connection.IsEstablished)
{
foreach (ulong streamId in client.Connection.Writable())
{
if (!client.PartialResponses.ContainsKey(streamId))
{
continue;
}
var partialResponse = client.PartialResponses[streamId];
var written = client.Connection.StreamSend(streamId, partialResponse.Body, true);
if (written < 0)
{
continue;
}
partialResponse.Written += written;
if (partialResponse.Written == partialResponse.Body.Length)
{
client.PartialResponses.Remove(streamId);
}
}
foreach (ulong streamId in client.Connection.Readable())
{
Debug.Log($"stream {streamId} is readable");
bool fin = false;
var readStream = client.Connection.StreamReceive(
streamId, streamRecv, ref fin);
if (readStream < 0)
{
continue;
}
if (fin)
{
var body = Encoding.ASCII.GetBytes("Hello World!\n");
var written = client.Connection.StreamSend(
streamId, body, true);
if (written < 0)
{
continue;
}
if (written < body.Length)
{
var partialResponse = new PartialResponse(body, written);
client.PartialResponses.Add(streamId, partialResponse);
}
}
}
}
}
