[client,relay] Add QUIC support (#2962)

relay/server/listener/quic/conn.go

@@ -0,0 +1,101 @@
+package quic
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"net"
+	"sync"
+	"time"
+
+	"github.com/quic-go/quic-go"
+)
+
+type Conn struct {
+	session   quic.Connection
+	closed    bool
+	closedMu  sync.Mutex
+	ctx       context.Context
+	ctxCancel context.CancelFunc
+}
+
+func NewConn(session quic.Connection) *Conn {
+	ctx, cancel := context.WithCancel(context.Background())
+	return &Conn{
+		session:   session,
+		ctx:       ctx,
+		ctxCancel: cancel,
+	}
+}
+
+func (c *Conn) Read(b []byte) (n int, err error) {
+	dgram, err := c.session.ReceiveDatagram(c.ctx)
+	if err != nil {
+		return 0, c.remoteCloseErrHandling(err)
+	}
+	// Copy data to b, ensuring we don’t exceed the size of b
+	n = copy(b, dgram)
+	return n, nil
+}
+
+func (c *Conn) Write(b []byte) (int, error) {
+	if err := c.session.SendDatagram(b); err != nil {
+		return 0, c.remoteCloseErrHandling(err)
+	}
+	return len(b), nil
+}
+
+func (c *Conn) LocalAddr() net.Addr {
+	return c.session.LocalAddr()
+}
+
+func (c *Conn) RemoteAddr() net.Addr {
+	return c.session.RemoteAddr()
+}
+
+func (c *Conn) SetReadDeadline(t time.Time) error {
+	return nil
+}
+
+func (c *Conn) SetWriteDeadline(t time.Time) error {
+	return fmt.Errorf("SetWriteDeadline is not implemented")
+}
+
+func (c *Conn) SetDeadline(t time.Time) error {
+	return fmt.Errorf("SetDeadline is not implemented")
+}
+
+func (c *Conn) Close() error {
+	c.closedMu.Lock()
+	if c.closed {
+		c.closedMu.Unlock()
+		return nil
+	}
+	c.closed = true
+	c.closedMu.Unlock()
+
+	c.ctxCancel() // Cancel the context
+
+	sessionErr := c.session.CloseWithError(0, "normal closure")
+	return sessionErr
+}
+
+func (c *Conn) isClosed() bool {
+	c.closedMu.Lock()
+	defer c.closedMu.Unlock()
+	return c.closed
+}
+
+func (c *Conn) remoteCloseErrHandling(err error) error {
+	if c.isClosed() {
+		return net.ErrClosed
+	}
+
+	// Check if the connection was closed remotely
+	var appErr *quic.ApplicationError
+	if errors.As(err, &appErr) && appErr.ErrorCode == 0x0 {
+		return net.ErrClosed
+	}
+
+	return err
+}

relay/server/listener/quic/listener.go

@@ -0,0 +1,66 @@
+package quic
+
+import (
+	"context"
+	"crypto/tls"
+	"errors"
+	"fmt"
+	"net"
+
+	"github.com/quic-go/quic-go"
+	log "github.com/sirupsen/logrus"
+)
+
+type Listener struct {
+	// Address is the address to listen on
+	Address string
+	// TLSConfig is the TLS configuration for the server
+	TLSConfig *tls.Config
+
+	listener *quic.Listener
+	acceptFn func(conn net.Conn)
+}
+
+func (l *Listener) Listen(acceptFn func(conn net.Conn)) error {
+	l.acceptFn = acceptFn
+
+	quicCfg := &quic.Config{
+		EnableDatagrams: true,
+	}
+	listener, err := quic.ListenAddr(l.Address, l.TLSConfig, quicCfg)
+	if err != nil {
+		return fmt.Errorf("failed to create QUIC listener: %v", err)
+	}
+
+	l.listener = listener
+	log.Infof("QUIC server listening on address: %s", l.Address)
+
+	for {
+		session, err := listener.Accept(context.Background())
+		if err != nil {
+			if errors.Is(err, quic.ErrServerClosed) {
+				return nil
+			}
+
+			log.Errorf("Failed to accept QUIC session: %v", err)
+			continue
+		}
+
+		log.Infof("QUIC client connected from: %s", session.RemoteAddr())
+		conn := NewConn(session)
+		l.acceptFn(conn)
+	}
+}
+
+func (l *Listener) Shutdown(ctx context.Context) error {
+	if l.listener == nil {
+		return nil
+	}
+
+	log.Infof("stopping QUIC listener")
+	if err := l.listener.Close(); err != nil {
+		return fmt.Errorf("listener shutdown failed: %v", err)
+	}
+	log.Infof("QUIC listener stopped")
+	return nil
+}

relay/server/listener/ws/listener.go

@@ -88,6 +88,8 @@ func (l *Listener) onAccept(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
+	log.Infof("WS client connected from: %s", rAddr)
+
 	conn := NewConn(wsConn, lAddr, rAddr)
 	l.acceptFn(conn)
 }

relay/server/relay.go

@@ -150,6 +150,8 @@ func (r *Relay) Accept(conn net.Conn) {
 func (r *Relay) Shutdown(ctx context.Context) {
 	log.Infof("close connection with all peers")
 	r.closeMu.Lock()
+	defer r.closeMu.Unlock()
+
 	wg := sync.WaitGroup{}
 	peers := r.store.Peers()
 	for _, peer := range peers {
@@ -161,7 +163,7 @@ func (r *Relay) Shutdown(ctx context.Context) {
 	}
 	wg.Wait()
 	r.metricsCancel()
-	r.closeMu.Unlock()
+	r.closed = true
 }
 
 // InstanceURL returns the instance URL of the relay server

relay/server/server.go

@@ -3,13 +3,17 @@ package server
 import (
 	"context"
 	"crypto/tls"
+	"sync"
 
-	log "github.com/sirupsen/logrus"
+	"github.com/hashicorp/go-multierror"
 	"go.opentelemetry.io/otel/metric"
 
+	nberrors "github.com/netbirdio/netbird/client/errors"
 	"github.com/netbirdio/netbird/relay/auth"
 	"github.com/netbirdio/netbird/relay/server/listener"
+	"github.com/netbirdio/netbird/relay/server/listener/quic"
 	"github.com/netbirdio/netbird/relay/server/listener/ws"
+	quictls "github.com/netbirdio/netbird/relay/tls"
 )
 
 // ListenerConfig is the configuration for the listener.
@@ -24,8 +28,8 @@ type ListenerConfig struct {
 // It is the gate between the WebSocket listener and the Relay server logic.
 // In a new HTTP connection, the server will accept the connection and pass it to the Relay server via the Accept method.
 type Server struct {
-	relay      *Relay
-	wSListener listener.Listener
+	relay     *Relay
+	listeners []listener.Listener
 }
 
 // NewServer creates a new relay server instance.
@@ -39,35 +43,63 @@ func NewServer(meter metric.Meter, exposedAddress string, tlsSupport bool, authV
 		return nil, err
 	}
 	return &Server{
-		relay: relay,
+		relay:     relay,
+		listeners: make([]listener.Listener, 0, 2),
 	}, nil
 }
 
 // Listen starts the relay server.
 func (r *Server) Listen(cfg ListenerConfig) error {
-	r.wSListener = &ws.Listener{
+	wSListener := &ws.Listener{
 		Address:   cfg.Address,
 		TLSConfig: cfg.TLSConfig,
 	}
+	r.listeners = append(r.listeners, wSListener)
 
-	wslErr := r.wSListener.Listen(r.relay.Accept)
-	if wslErr != nil {
-		log.Errorf("failed to bind ws server: %s", wslErr)
+	tlsConfigQUIC, err := quictls.ServerQUICTLSConfig(cfg.TLSConfig)
+	if err != nil {
+		return err
 	}
 
-	return wslErr
+	quicListener := &quic.Listener{
+		Address:   cfg.Address,
+		TLSConfig: tlsConfigQUIC,
+	}
+
+	r.listeners = append(r.listeners, quicListener)
+
+	errChan := make(chan error, len(r.listeners))
+	wg := sync.WaitGroup{}
+	for _, l := range r.listeners {
+		wg.Add(1)
+		go func(listener listener.Listener) {
+			defer wg.Done()
+			errChan <- listener.Listen(r.relay.Accept)
+		}(l)
+	}
+
+	wg.Wait()
+	close(errChan)
+	var multiErr *multierror.Error
+	for err := range errChan {
+		multiErr = multierror.Append(multiErr, err)
+	}
+
+	return nberrors.FormatErrorOrNil(multiErr)
 }
 
 // Shutdown stops the relay server. If there are active connections, they will be closed gracefully. In case of a context,
 // the connections will be forcefully closed.
-func (r *Server) Shutdown(ctx context.Context) (err error) {
-	// stop service new connections
-	if r.wSListener != nil {
-		err = r.wSListener.Shutdown(ctx)
-	}
-
+func (r *Server) Shutdown(ctx context.Context) error {
 	r.relay.Shutdown(ctx)
-	return
+
+	var multiErr *multierror.Error
+	for _, l := range r.listeners {
+		if err := l.Shutdown(ctx); err != nil {
+			multiErr = multierror.Append(multiErr, err)
+		}
+	}
+	return nberrors.FormatErrorOrNil(multiErr)
 }
 
 // InstanceURL returns the instance URL of the relay server.