X-Git-Url: http://www.git.cypherpunks.ru/?a=blobdiff_plain;f=src%2Fmcd.go;h=b4de4f4cb602c97f0ced66027d744ca7441a03db;hb=0367cce2741e1ce6a89a49fd5c4e9df6005c9744;hp=d785d5c64b9461f1636de0220f37d9dde7fc73b5;hpb=512f39be16c63a9ab0a9f27d40c9cfbb2339f9c2;p=nncp.git

diff --git a/src/mcd.go b/src/mcd.go
index d785d5c..b4de4f4 100644
--- a/src/mcd.go
+++ b/src/mcd.go
@@ -1,6 +1,6 @@
 /*
 NNCP -- Node to Node copy, utilities for store-and-forward data exchange
-Copyright (C) 2016-2021 Sergey Matveev <stargrave@stargrave.org>
+Copyright (C) 2016-2022 Sergey Matveev <stargrave@stargrave.org>
 
 This program is free software: you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
@@ -43,8 +43,6 @@ type MCDAddr struct {
 }
 
 var (
-	MagicNNCPDv1 [8]byte = [8]byte{'N', 'N', 'C', 'P', 'D', 0, 0, 1}
-
 	mcdIP           = net.ParseIP("ff02::4e4e:4350")
 	mcdAddrLifetime = 2 * time.Minute
 
@@ -125,7 +123,7 @@ func (ctx *Ctx) MCDRx(ifiName string) error {
 				})
 				continue
 			}
-			if mcd.Magic != MagicNNCPDv1 {
+			if mcd.Magic != MagicNNCPDv1.B {
 				ctx.LogD("mcd", les, func(les LEs) string {
 					return fmt.Sprintf(
 						"MCD Rx %s/%d: unexpected magic: %s",
@@ -178,20 +176,24 @@ func (ctx *Ctx) MCDRx(ifiName string) error {
 }
 
 func (ctx *Ctx) MCDTx(ifiName string, port int, interval time.Duration) error {
-	conn, err := net.DialUDP("udp",
-		&net.UDPAddr{Port: port, Zone: ifiName},
-		&net.UDPAddr{IP: mcdIP, Port: MCDPort, Zone: ifiName},
-	)
+	ifi, err := net.InterfaceByName(ifiName)
 	if err != nil {
 		return err
 	}
+	addr := &net.UDPAddr{IP: mcdIP, Port: port, Zone: ifiName}
+	conn, err := net.ListenMulticastUDP("udp", ifi, addr)
+	if err != nil {
+		return err
+	}
+
+	dst := &net.UDPAddr{IP: mcdIP, Port: MCDPort, Zone: ifiName}
 	var buf bytes.Buffer
-	mcd := MCD{Magic: MagicNNCPDv1, Sender: ctx.Self.Id}
+	mcd := MCD{Magic: MagicNNCPDv1.B, Sender: ctx.Self.Id}
 	if _, err := xdr.Marshal(&buf, mcd); err != nil {
 		panic(err)
 	}
 	if interval == 0 {
-		_, err = conn.Write(buf.Bytes())
+		_, err = conn.WriteTo(buf.Bytes(), dst)
 		return err
 	}
 	go func() {
@@ -203,7 +205,7 @@ func (ctx *Ctx) MCDTx(ifiName string, port int, interval time.Duration) error {
 					ifiName, MCDPort, port,
 				)
 			})
-			_, err = conn.Write(buf.Bytes())
+			_, err = conn.WriteTo(buf.Bytes(), dst)
 			if err != nil {
 				ctx.LogE("mcd", les, err, func(les LEs) string {
 					return fmt.Sprintf("MCD on %s/%d/%d", ifiName, MCDPort, port)