From aff779b6f9c75523d491e1003c0c2d589c1eca20 Mon Sep 17 00:00:00 2001
From: Sergey Matveev <stargrave@stargrave.org>
Date: Mon, 19 Jul 2021 19:43:46 +0300
Subject: [PATCH] SO_REUSEPORT is applied only to multicast UDP ports

---
 doc/news.ru.texi    | 10 ++++++++++
 doc/news.texi       |  9 +++++++++
 ports/nncp/Makefile |  2 +-
 src/mcd.go          | 16 ++++++++++------
 src/nncp.go         |  2 +-
 5 files changed, 31 insertions(+), 8 deletions(-)

diff --git a/doc/news.ru.texi b/doc/news.ru.texi
index 59dae28..8d0bca9 100644
--- a/doc/news.ru.texi
+++ b/doc/news.ru.texi
@@ -1,6 +1,16 @@
 @node Новости
 @section Новости
 
+@node Релиз 7.4.0
+@subsection Релиз 7.4.0
+@itemize
+
+@item
+Исправлена работоспособность MCD при одновременном использовании
+@command{nncp-daemon} и @command{nncp-caller}.
+
+@end itemize
+
 @node Релиз 7.3.2
 @subsection Релиз 7.3.2
 @itemize
diff --git a/doc/news.texi b/doc/news.texi
index 4b6bb4c..c9106f8 100644
--- a/doc/news.texi
+++ b/doc/news.texi
@@ -3,6 +3,15 @@
 
 See also this page @ref{Новости, on russian}.
 
+@node Release 7_4_0
+@section Release 7.4.0
+@itemize
+
+@item
+Fixed simultaneous @command{nncp-daemon} and @command{nncp-caller} MCD work.
+
+@end itemize
+
 @node Release 7_3_2
 @section Release 7.3.2
 @itemize
diff --git a/ports/nncp/Makefile b/ports/nncp/Makefile
index d18cf56..70b6311 100644
--- a/ports/nncp/Makefile
+++ b/ports/nncp/Makefile
@@ -1,5 +1,5 @@
 PORTNAME=	nncp
-DISTVERSION=	7.3.2
+DISTVERSION=	7.4.0
 CATEGORIES=	net
 MASTER_SITES=	http://www.nncpgo.org/download/
 
diff --git a/src/mcd.go b/src/mcd.go
index be40f42..60ca6a5 100644
--- a/src/mcd.go
+++ b/src/mcd.go
@@ -176,20 +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.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() {
@@ -201,7 +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)
diff --git a/src/nncp.go b/src/nncp.go
index 94e1df8..64489bc 100644
--- a/src/nncp.go
+++ b/src/nncp.go
@@ -40,7 +40,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.`
 const Base32Encoded32Len = 52
 
 var (
-	Version string = "7.3.2"
+	Version string = "7.4.0"
 
 	Base32Codec *base32.Encoding = base32.StdEncoding.WithPadding(base32.NoPadding)
 )
-- 
2.44.0