From 767e1c6f589c6c2c5409e0e042a9528e37269499 Mon Sep 17 00:00:00 2001
From: Simon Frei <freisim93@gmail.com>
Date: Fri, 5 Mar 2021 08:06:37 +0100
Subject: [PATCH] lib/connections: Expose SetReadBuffer on conn passed to quic
 (ref #7417) (#7432)

---
 lib/connections/quic_listen.go | 20 +++++++++++++++++---
 1 file changed, 17 insertions(+), 3 deletions(-)

diff --git a/lib/connections/quic_listen.go b/lib/connections/quic_listen.go
index 62b40bb99..ada6429ca 100644
--- a/lib/connections/quic_listen.go
+++ b/lib/connections/quic_listen.go
@@ -90,13 +90,17 @@ func (t *quicListener) serve(ctx context.Context) error {
 
 	svc, conn := stun.New(t.cfg, t, packetConn)
 	defer func() { _ = conn.Close() }()
+	wrapped := &stunConnQUICWrapper{
+		PacketConn: conn,
+		underlying: packetConn.(*net.UDPConn),
+	}
 
 	go svc.Serve(ctx)
 
-	registry.Register(t.uri.Scheme, conn)
-	defer registry.Unregister(t.uri.Scheme, conn)
+	registry.Register(t.uri.Scheme, wrapped)
+	defer registry.Unregister(t.uri.Scheme, wrapped)
 
-	listener, err := quic.Listen(conn, t.tlsCfg, quicConfig)
+	listener, err := quic.Listen(wrapped, t.tlsCfg, quicConfig)
 	if err != nil {
 		l.Infoln("Listen (BEP/quic):", err)
 		return err
@@ -213,3 +217,13 @@ func (f *quicListenerFactory) New(uri *url.URL, cfg config.Wrapper, tlsCfg *tls.
 func (quicListenerFactory) Enabled(cfg config.Configuration) bool {
 	return true
 }
+
+type stunConnQUICWrapper struct {
+	net.PacketConn
+	underlying *net.UDPConn
+}
+
+// SetReadBuffer is required by QUIC.
+func (s *stunConnQUICWrapper) SetReadBuffer(size int) error {
+	return s.underlying.SetReadBuffer(size)
+}