add new metadata for dtls

listener/dtls/listener.go

@@ -66,8 +66,10 @@ func (l *dtlsListener) Init(md md.Metadata) (err error) {
 		ConnectContextMaker: func() (context.Context, func()) {
 			return context.WithTimeout(context.Background(), 30*time.Second)
 		},
-		ClientCAs:  tlsCfg.ClientCAs,
-		ClientAuth: dtls.ClientAuthType(tlsCfg.ClientAuth),
+		ClientCAs:      tlsCfg.ClientCAs,
+		ClientAuth:     dtls.ClientAuthType(tlsCfg.ClientAuth),
+		FlightInterval: l.md.flightInterval,
+		MTU:            l.md.mtu,
 	}
 
 	ln, err := dtls.Listen(network, laddr, &config)

listener/dtls/metadata.go

@@ -1,12 +1,25 @@
 package dtls
 
 import (
+	"time"
+
 	mdata "github.com/go-gost/core/metadata"
+	mdutil "github.com/go-gost/core/metadata/util"
 )
 
 type metadata struct {
+	mtu            int
+	flightInterval time.Duration
 }
 
 func (l *dtlsListener) parseMetadata(md mdata.Metadata) (err error) {
-	return
+	const (
+		mtu            = "mtu"
+		flightInterval = "flightInterval"
+	)
+
+	l.md.mtu = mdutil.GetInt(md, mtu)
+	l.md.flightInterval = mdutil.GetDuration(md, flightInterval)
+
+	return nil
 }