From 3edaf6728f27b36d74a45c6a830a05b6372f62d4 Mon Sep 17 00:00:00 2001
From: EndMove <superjeremi1302@gmail.com>
Date: Mon, 14 Mar 2022 11:40:23 +0100
Subject: [PATCH] Ajout de la prise en compte d'interface pour le multicast

---
 pkg/network/ClientMulticast.go | 21 ++++++++++-----------
 pkg/utils/FileReceiver.go      |  8 --------
 pkg/utils/Network.go           | 21 +++++++++++++++++++++
 3 files changed, 31 insertions(+), 19 deletions(-)

diff --git a/pkg/network/ClientMulticast.go b/pkg/network/ClientMulticast.go
index 49f97c6..8c82753 100644
--- a/pkg/network/ClientMulticast.go
+++ b/pkg/network/ClientMulticast.go
@@ -3,6 +3,7 @@ package network
 import (
 	"StoreBackEnd/pkg/protocol/repository"
 	"StoreBackEnd/pkg/protocol/rules/writers"
+	"StoreBackEnd/pkg/utils"
 	"fmt"
 	"net"
 	"time"
@@ -48,6 +49,7 @@ func (client ClientMulticast) Run() {
 	// Resolve interface addr
 	lAddr, failedRIA := ResolveInterfaceAddr(client.netInter)
 	if failedRIA {
+		println("Error : No IPv4 found in interface")
 		return
 	}
 
@@ -81,21 +83,18 @@ func (client ClientMulticast) ResolveAddr() (*net.UDPAddr, bool) {
 
 // ResolveInterfaceAddr Resolves the network interface address.
 func ResolveInterfaceAddr(inter string) (*net.UDPAddr, bool) {
-	//ief, _ := net.InterfaceByName(inter)
-	//addrs, _ := ief.Addrs()
-	//for _, addr := range addrs {
-	//	if utils.IsIPv4(addr.String()) {
-	//		println("Selected IP", addr.String())
-	//		lAddr, _ := net.ResolveUDPAddr("udp", "127.0.0.1:15502")
-	//		return lAddr, false
-	//	}
-	//}
-	return nil, false
+	ip, err := utils.RetrieveIPv4FromInterface(inter)
+	if err != nil {
+		println("Error : " + err.Error())
+		return nil, true
+	}
+	println("Selected IP : " + ip.String())
+	return &net.UDPAddr{IP: ip}, false
 }
 
 // DialUdp Ouvre une connection UDP
 func (client ClientMulticast) DialUdp(lAddr *net.UDPAddr, rAddr *net.UDPAddr) (*net.UDPConn, bool) {
-	con, errDial := net.DialUDP("udp", nil, rAddr)
+	con, errDial := net.DialUDP("udp", lAddr, rAddr)
 	if errDial != nil {
 		println(errDial.Error())
 		return nil, true
diff --git a/pkg/utils/FileReceiver.go b/pkg/utils/FileReceiver.go
index fc4e075..aaac2fe 100644
--- a/pkg/utils/FileReceiver.go
+++ b/pkg/utils/FileReceiver.go
@@ -44,11 +44,3 @@ func copyFile(currentSize int, fileSize int, reader *bufio.Reader, buffer []byte
 	}
 	return false, false
 }
-
-func fileExists(filename string) bool {
-	info, err := os.Stat(filename)
-	if os.IsNotExist(err) {
-		return false
-	}
-	return !info.IsDir()
-}
diff --git a/pkg/utils/Network.go b/pkg/utils/Network.go
index 607d42c..a8ceddc 100644
--- a/pkg/utils/Network.go
+++ b/pkg/utils/Network.go
@@ -1,6 +1,7 @@
 package utils
 
 import (
+	"errors"
 	"fmt"
 	"net"
 	"strings"
@@ -29,6 +30,26 @@ func NetworkLister() {
 	print("\n")
 }
 
+// RetrieveIPv4FromInterface Retrieve the first IPv4 from an interface.
+func RetrieveIPv4FromInterface(inter string) (net.IP, error) {
+	ief, err := net.InterfaceByName(inter)
+	addrs, err := ief.Addrs()
+	if err != nil {
+		return nil, err
+	}
+	for _, addr := range addrs {
+		switch v := addr.(type) {
+		case *net.IPNet:
+			//if !v.IP.IsLoopback() {
+			if v.IP.To4() != nil { //Verify if IP is IPV4
+				return v.IP, nil
+			}
+			//}
+		}
+	}
+	return nil, errors.New("no IPv4 found")
+}
+
 // IsIPv4 Check if the ip is a v4 or v6 ip
 func IsIPv4(addr string) bool {
 	return strings.Count(addr, ":") < 2