return specific errors; update readme

README.md

@@ -385,11 +385,13 @@ by adding account management and it is one of the easiest way to start.
  - [x] Stateless reset key for the server
  - [x] Name access restrictions for clients
  - [x] File http server
- - [ ] Use quic-go tracer, instead of ping (and duration estimation)
+ - [x] Use quic-go tracer, instead of ping (and duration estimation)
  - [ ] error wrapping
 
 ## Future
 
  - [ ] UDP support
  - [ ] Optimize global IP restrictions - check earlier
  - [ ] Gen config
+ - [ ] proxy proto support
+ - [ ] http source

client/peer_direct.go

@@ -303,7 +303,7 @@ func (p *directPeerOutgoing) connect(ctx context.Context) (quic.Connection, erro
 		}
 
 		if err := p.check(ctx, conn); err != nil {
-			// TODO conn close?
+			conn.CloseWithError(quic.ApplicationErrorCode(pb.Error_CheckFailed), "connection check failed")
 			errs = append(errs, err)
 			continue
 		}

client/peer_relay.go

@@ -99,7 +99,7 @@ func (r *relayPeer) connect(ctx context.Context) (quic.Connection, error) {
 	}
 
 	if err := r.check(ctx, conn); err != nil {
-		// TODO conn close?
+		conn.CloseWithError(quic.ApplicationErrorCode(pb.Error_CheckFailed), "connection check failed")
 		return nil, err
 	}
 	return conn, nil
@@ -123,7 +123,7 @@ func (r *relayPeer) check(ctx context.Context, conn quic.Connection) error {
 }
 
 func (r *relayPeer) keepalive(ctx context.Context, conn quic.Connection) error {
-	defer conn.CloseWithError(quic.ApplicationErrorCode(pb.Error_DirectKeepaliveClosed), "keepalive closed") // TODO relay?
+	defer conn.CloseWithError(quic.ApplicationErrorCode(pb.Error_RelayKeepaliveClosed), "keepalive closed")
 
 	r.local.addRelayConn(r.serverHostport, conn)
 	defer r.local.removeRelayConn(r.serverHostport)

pb/shared.proto

@@ -36,6 +36,7 @@ message Error {
     // Generic
     Unknown = 0;
     RequestUnknown = 1;
+    CheckFailed = 2;
 
     // Authentication
     AuthenticationFailed = 100;
@@ -49,6 +50,7 @@ message Error {
     // Relay
     RelayValidationFailed = 300;
     RelayInvalidCertificate = 301;
+    RelayKeepaliveClosed = 302;
 
     // Direct
     DirectConnectionClosed = 400;