NET-715: Ability to set custom interface names (#626)

* interface set command,allow multiple docker containers to run on same host

* set interface name on init

* add flag to restart daemon on interface cmd

* save config to disk

* set interface on daemon startup

* add check to validate interface name

* don't restart on setting interface in docker to avoid duplicacy

* remove exact args

* set interface before installing

* set iface name

* add interface flag to join,push cmds

* add iface args to docker script

* remove darwin check

* delete ifaces

* push trap cmd to background

* fix if stmt in script

* fix if stmt in script

* fix docker script

* rm sleep

* wait on trap command

* fix cleanup cmd

* rm debug stmts

* delete only interface spun by this container

* fix overriting of config from in memory

cmd/join.go

@@ -23,6 +23,7 @@ user: netclient join -s <server> -u <user_name> // attempt to join/register via
 
 	Run: func(cmd *cobra.Command, args []string) {
 		setHostFields(cmd)
+		functions.Push(false)
 		token, err := cmd.Flags().GetString(registerFlags.Token)
 		if err != nil || len(token) == 0 {
 			if regErr := checkUserRegistration(cmd); regErr != nil {
@@ -48,5 +49,6 @@ func init() {
 	joinCmd.Flags().StringP(registerFlags.MTU, "m", "", "sets MTU on host")
 	joinCmd.Flags().BoolP(registerFlags.Static, "i", false, "flag to set host as static")
 	joinCmd.Flags().StringP(registerFlags.Name, "o", "", "sets host name")
+	joinCmd.Flags().StringP(registerFlags.Interface, "I", "", "sets netmaker interface to use on host")
 	rootCmd.AddCommand(joinCmd)
 }

cmd/push.go

@@ -13,7 +13,7 @@ var pushCmd = &cobra.Command{
 	Long:  `updates host config locally and updates server`,
 	Run: func(cmd *cobra.Command, args []string) {
 		setHostFields(cmd)
-		err := functions.Push()
+		err := functions.Push(true)
 		if err != nil {
 			logger.Log(0, "failed to push", err.Error())
 		}
@@ -26,5 +26,6 @@ func init() {
 	pushCmd.Flags().IntP(registerFlags.MTU, "m", 0, "sets MTU on host")
 	pushCmd.Flags().BoolP(registerFlags.Static, "i", false, "flag to set host as static")
 	pushCmd.Flags().StringP(registerFlags.Name, "o", "", "sets host name")
+	pushCmd.Flags().StringP(registerFlags.Interface, "I", "", "sets netmaker interface to use on host")
 	rootCmd.AddCommand(pushCmd)
 }

cmd/register.go

@@ -7,6 +7,8 @@ import (
 	"fmt"
 	"net"
 	"os"
+	"runtime"
+	"strings"
 	"syscall"
 
 	"github.com/gravitl/netclient/config"
@@ -27,6 +29,7 @@ var registerFlags = struct {
 	Port        string
 	MTU         string
 	Static      string
+	Interface   string
 	Name        string
 }{
 	Server:      "server",
@@ -39,6 +42,7 @@ var registerFlags = struct {
 	MTU:         "mtu",
 	Static:      "static",
 	Name:        "name",
+	Interface:   "interface",
 }
 
 // registerCmd represents the register command
@@ -53,6 +57,7 @@ all-networks: netclient register -s <server> -A // attempt to register to all al
 user: netclient register -s <server> -u <user_name> // attempt to join/register via basic auth`,
 	Run: func(cmd *cobra.Command, args []string) {
 		setHostFields(cmd)
+		functions.Push(false)
 		token, err := cmd.Flags().GetString(registerFlags.Token)
 		if err != nil || len(token) == 0 {
 			if regErr := checkUserRegistration(cmd); regErr != nil {
@@ -86,11 +91,44 @@ func setHostFields(cmd *cobra.Command) {
 	if hostName, err := cmd.Flags().GetString(registerFlags.Name); err == nil && hostName != "" {
 		config.Netclient().Name = hostName
 	}
-
+	if ifaceName, err := cmd.Flags().GetString(registerFlags.Interface); err == nil && ifaceName != "" {
+		if !validateIface(ifaceName) {
+			fmt.Println("invalid interface name", ifaceName)
+			os.Exit(1)
+		}
+		config.Netclient().Interface = ifaceName
+	}
 	if isStatic, err := cmd.Flags().GetBool(registerFlags.Static); err == nil {
 		config.Netclient().IsStatic = isStatic
 	}
 }
+func validateIface(iface string) bool {
+	if iface == "" {
+		return false
+	}
+	exists, err := ncutils.InterfaceExists(iface)
+	if err != nil {
+		fmt.Println("error checking for interfaces ", err)
+		return false
+	}
+	if exists {
+		fmt.Printf("iface `%s` already exists\n", iface)
+		return false
+	}
+	if iface == "netmaker-test" || iface == "utun70" {
+		fmt.Println("cannot use `netmaker-test` interface")
+		return false
+	}
+	if runtime.GOOS == "darwin" && !strings.HasPrefix(iface, "utun") {
+		fmt.Println("use utun as interface on darwin")
+		return false
+	}
+	if runtime.GOOS != "darwin" && !strings.HasPrefix(iface, "netmaker") {
+		fmt.Println("invalid interface name, should contain `netmaker` as prefix")
+		return false
+	}
+	return true
+}
 
 func checkUserRegistration(cmd *cobra.Command) error {
 	apiURI, err := cmd.Flags().GetString(registerFlags.Server)
@@ -140,5 +178,6 @@ func init() {
 	registerCmd.Flags().IntP(registerFlags.MTU, "m", 0, "sets MTU on host")
 	registerCmd.Flags().BoolP(registerFlags.Static, "i", false, "flag to set host as static")
 	registerCmd.Flags().StringP(registerFlags.Name, "o", "", "sets host name")
+	registerCmd.Flags().StringP(registerFlags.Interface, "I", "", "sets netmaker interface to use on host")
 	rootCmd.AddCommand(registerCmd)
 }

cmd/root.go

@@ -17,7 +17,6 @@ import (
 	"github.com/gravitl/netclient/ncutils"
 	"github.com/gravitl/netclient/wireguard"
 	"github.com/gravitl/netmaker/logger"
-	"github.com/gravitl/netmaker/models"
 	"github.com/spf13/cobra"
 	"github.com/spf13/viper"
 	"golang.org/x/crypto/nacl/box"
@@ -79,6 +78,9 @@ func initConfig() {
 func InitConfig(viper *viper.Viper) {
 	config.CheckUID()
 	config.ReadNetclientConfig()
+	if config.Netclient().Interface != "" {
+		ncutils.SetInterfaceName(config.Netclient().Interface)
+	}
 	setupLogging(viper)
 	config.ReadNodeConfig()
 	config.ReadServerConf()
@@ -202,7 +204,7 @@ func checkConfig() {
 	}
 	if netclient.Interface == "" {
 		logger.Log(0, "setting wireguard interface")
-		netclient.Interface = models.WIREGUARD_INTERFACE
+		netclient.Interface = ncutils.GetInterfaceName()
 		saveRequired = true
 	}
 	if netclient.ListenPort == 0 {

functions/daemon.go

@@ -119,6 +119,7 @@ func startGoRoutines(wg *sync.WaitGroup) context.CancelFunc {
 		slog.Error("error reading netclient config file", "error", err)
 	}
 	config.UpdateNetclient(*config.Netclient())
+	ncutils.SetInterfaceName(config.Netclient().Interface)
 	if err := config.ReadServerConf(); err != nil {
 		slog.Warn("error reading server map from disk", "error", err)
 	}

functions/localport.go

@@ -39,7 +39,7 @@ func getInterfaces() (*[]models.Iface, error) {
 		if iface.Flags&net.FlagUp == 0 || // interface down
 			iface.Flags&net.FlagLoopback != 0 || // loopback interface
 			iface.Flags&net.FlagPointToPoint != 0 || // avoid direct connections
-			iface.Name == ncutils.GetInterfaceName() || // avoid netmaker
+			iface.Name == ncutils.GetInterfaceName() || strings.Contains(iface.Name, "netmaker") || // avoid netmaker
 			ncutils.IsBridgeNetwork(iface.Name) || // avoid bridges
 			strings.Contains(iface.Name, "docker") {
 			continue

functions/push.go

@@ -1,7 +1,6 @@
 package functions
 
 import (
-	"errors"
 	"fmt"
 
 	"github.com/gravitl/netclient/config"
@@ -10,24 +9,26 @@ import (
 )
 
 // Push - updates server with new host config
-func Push() error {
+func Push(restart bool) error {
 	server := config.GetServer(config.CurrServer)
-	if server == nil {
-		return errors.New("server cfg is nil")
-	}
-	if err := setupMQTTSingleton(server, true); err != nil {
-		return err
-	}
-	if err := PublishHostUpdate(server.Server, models.UpdateHost); err != nil {
-		return err
+	if server != nil {
+		if err := setupMQTTSingleton(server, true); err != nil {
+			return err
+		}
+		if err := PublishHostUpdate(server.Server, models.UpdateHost); err != nil {
+			return err
+		}
 	}
 	if err := config.WriteNetclientConfig(); err != nil {
 		return err
 	}
-	if err := daemon.Restart(); err != nil {
-		if err := daemon.Start(); err != nil {
-			return fmt.Errorf("daemon restart failed %w", err)
+	if restart {
+		if err := daemon.Restart(); err != nil {
+			if err := daemon.Start(); err != nil {
+				return fmt.Errorf("daemon restart failed %w", err)
+			}
 		}
 	}
+
 	return nil
 }

ncutils/netclientutils.go

@@ -26,6 +26,8 @@ import (
 	"github.com/gravitl/netmaker/models"
 )
 
+var ifaceName string
+
 // MaxNameLength - maximum node name length
 const MaxNameLength = 62
 
@@ -538,8 +540,18 @@ func IPIsPrivate(ipnet net.IP) bool {
 	return ipnet.IsPrivate() || ipnet.IsLoopback()
 }
 
+func SetInterfaceName(iface string) {
+	if runtime.GOOS == "darwin" && !strings.HasPrefix(iface, "utun") {
+		return
+	}
+	ifaceName = iface
+}
+
 // GetInterfaceName - fetches the interface name
 func GetInterfaceName() string {
+	if ifaceName != "" {
+		return ifaceName
+	}
 	if runtime.GOOS == "darwin" {
 		return "utun69"
 	}
@@ -579,3 +591,17 @@ func RandomString(length int) string {
 func ConvHostPassToHash(hostPass string) string {
 	return fmt.Sprintf("%x", md5.Sum([]byte(hostPass)))
 }
+
+// InterfaceExists - checks if iface exists already
+func InterfaceExists(ifaceName string) (bool, error) {
+	interfaces, err := net.Interfaces()
+	if err != nil {
+		return false, err
+	}
+	for _, inet := range interfaces {
+		if inet.Name == ifaceName {
+			return true, nil
+		}
+	}
+	return false, nil
+}

scripts/netclient.sh

@@ -3,15 +3,14 @@
 sh -c rc-status
 #Define cleanup
 cleanup() {
-    nets=($(wg show interfaces))
-    for net in ${nets[@]}; do
-        echo "deleting interface" $net
-        ip link del $net
-    done
+    echo "deleting interface" $net
+    if [ "${IFACE_NAME}" == "" ];then
+        IFACE_NAME="netmaker"
+    fi
+    ip link del $IFACE_NAME
 }
 
-#Trap SigTerm
-trap 'cleanup' SIGTERM
+
 
 # install netclient
 echo "[netclient] starting netclient daemon"
@@ -59,8 +58,20 @@ STATIC_CMD=""
 if [ "${IS_STATIC}" != "" ];then
     STATIC_CMD="-i ${IS_STATIC}"
 fi
+IFACE_CMD=""
+if [ "${IFACE_NAME}" != "" ];then
+    IFACE_CMD="-I ${IFACE_NAME}"
+fi
 
-netclient join $TOKEN_CMD $PORT_CMD $ENDPOINT_CMD $MTU_CMD $HOSTNAME_CMD $STATIC_CMD
-if [ $? -ne 0 ]; then { echo "failed to join, quitting." ; exit 1; } fi
+echo "[netclient] Starting netclient daemon"
+/root/netclient install
+wait $!
+netclient join $TOKEN_CMD $PORT_CMD $ENDPOINT_CMD $MTU_CMD $HOSTNAME_CMD $STATIC_CMD $IFACE_CMD
+if [ $? -ne 0 ]; then { echo "Failed to join, quitting." ; exit 1; } fi
 
-sleep infinity
+tail -f /var/log/netclient.log &
+
+#Trap SigTerm
+trap 'cleanup' SIGTERM
+
+wait $!