void AddToPendingPeers(ConnectedPeerType type, IPEndPoint remoteEndpoint, SocketWithReceiver socket)
{
var cp = new ConnectedPeer(_localPeer, null, type, remoteEndpoint.Address);
cp.TryAddStream(socket, remoteEndpoint, null, _pendingPeers.Values.Select(x => x.Streams.Values.Single().StreamId));
// all "pending" streams will have unique local stream ID
_pendingPeers.Add(remoteEndpoint, cp);
}
void ProcessReceivedHello_FromExistingPeer(PeerHelloPacket helloPacket, IPEndPoint remoteEndpoint, SocketWithReceiver socket, ConnectedPeer connectedPeer, uint packetReceivedTimestamp32)
{
// current situation:
// received hello packet; this peer wants to accept connection
// in hello packet FromPeerId matches to existing connected peer
// there is already at least 1 stream in the existing peer; it could be request via this stream or via another stream
// it could be request (ping) or response
// it could be packet to new stream, or to existing stream
// it could be packet from changed remote endpoint to same stream ID
// it could be packet from wrong remote endpoint to new (non-existing locally) stream ID ???????????????????????
if (!connectedPeer.Streams.TryGetValue(helloPacket.StreamId, out var stream))
{ // received packet in new streamId
if (helloPacket.Status.IsSetupOrPing())
{
if (connectedPeer.Streams.Count > LocalLogicConfiguration.ConnectedPeerMaxStreamsCount)
{
_localPeer.WriteToLog_deepDetail(LogModules.Hello, $"rejecting request from {remoteEndpoint}: connectedPeer.Streams.Count={connectedPeer.Streams.Count} > LocalLogicConfiguration.ConnectedPeerMaxStreamsCount");
PeerHelloPacket.Respond(helloPacket, PeerHelloRequestStatus.rejected_dontTryLater, null, socket, remoteEndpoint);
return;
}
stream = connectedPeer.TryAddStream(socket, remoteEndpoint, helloPacket.StreamId);
// _localPeer.WriteToLog(LogModules.Hello, $"peer {connectedPeer} received hello from new stream {stream}");
if (stream == null)
{
throw new InvalidOperationException();
}
}
else
{
_localPeer.Firewall.OnUnauthenticatedReceivedPacket(remoteEndpoint);
return;
}
}
else
{// received packet in existing streamId
// check source endpoint
if (!remoteEndpoint.Equals(stream.RemoteEndPoint))
{ // dont allow change of source ip/port within same stream
_localPeer.Firewall.OnUnauthenticatedReceivedPacket(remoteEndpoint);
if (helloPacket.Status.IsSetupOrPing())
{
PeerHelloPacket.Respond(helloPacket, PeerHelloRequestStatus.rejected_tryCleanSetup, null, socket, remoteEndpoint);
}
return;
}
}
// current situation: we got connectedPeer, stream. we handle request or response
if (!RemoteVersionIsAcceptableForNewConnection(helloPacket))
{
_localPeer.WriteToLog_deepDetail(LogModules.Hello, $"peer {connectedPeer} got response with too old version");
connectedPeer.RemoveStream(stream);
_connectedPeers.Remove(connectedPeer.RemotePeerId);
return;
}
switch (helloPacket.Status)
{
case PeerHelloRequestStatus.setup:
case PeerHelloRequestStatus.ping:
var responseCpuDelayMs = (ushort)Math.Round(TimeSpan.FromTicks(unchecked (_localPeer.Time32 - packetReceivedTimestamp32)).TotalMilliseconds);
PeerHelloPacket.Respond(helloPacket, PeerHelloRequestStatus.accepted, null, socket, remoteEndpoint, responseCpuDelayMs, _localPeer.Configuration.RoleAsUser, _localPeer.IpLocationScraper?.IpLocationData);
break;
case PeerHelloRequestStatus.accepted:
ProcessReceivedAcceptedHello_UpdateHelloLevelFields(connectedPeer, stream, helloPacket, packetReceivedTimestamp32);
break;
case PeerHelloRequestStatus.rejected_tryCleanSetup:
_localPeer.WriteToLog_deepDetail(LogModules.Hello, $"peer {connectedPeer} received {helloPacket.Status} from stream {stream}");
connectedPeer.RemoveStream(stream);
AddToPendingPeers(connectedPeer.Type, remoteEndpoint, socket);
break;
case PeerHelloRequestStatus.rejected_dontTryLater:
_localPeer.WriteToLog_deepDetail(LogModules.Hello, $"peer {connectedPeer} received {helloPacket.Status} from stream {stream}");
connectedPeer.RemoveStream(stream);
break;
case PeerHelloRequestStatus.rejected_tryLater:
_localPeer.WriteToLog_deepDetail(LogModules.Hello, $"peer {connectedPeer} received {helloPacket.Status} from stream {stream}");
// it will try anyway on timer
break;
}
}
