pass a conn to qtls that returns the remote address

internal/handshake/qtls.go

@@ -2,11 +2,32 @@ package handshake
 
 import (
 	"crypto/tls"
+	"net"
+	"time"
 	"unsafe"
 
 	"github.com/marten-seemann/qtls"
 )
 
+type conn struct {
+	remoteAddr net.Addr
+}
+
+func newConn(remote net.Addr) net.Conn {
+	return &conn{remoteAddr: remote}
+}
+
+var _ net.Conn = &conn{}
+
+func (c *conn) Read([]byte) (int, error)         { return 0, nil }
+func (c *conn) Write([]byte) (int, error)        { return 0, nil }
+func (c *conn) Close() error                     { return nil }
+func (c *conn) RemoteAddr() net.Addr             { return c.remoteAddr }
+func (c *conn) LocalAddr() net.Addr              { return nil }
+func (c *conn) SetReadDeadline(time.Time) error  { return nil }
+func (c *conn) SetWriteDeadline(time.Time) error { return nil }
+func (c *conn) SetDeadline(time.Time) error      { return nil }
+
 type clientSessionCache struct {
 	tls.ClientSessionCache
 }