Fix concurrency on the client (#183)

* reworked peer connection establishment logic eliminating race conditions and deadlocks while running many peers

iface/iface.go

@@ -17,8 +17,6 @@ const (
 
 var (
 	tunIface tun.Device
-	// todo check after move the WgPort constant to the client
-	WgPort = 51820
 )
 
 // CreateWithUserspace Creates a new Wireguard interface, using wireguard-go userspace implementation
@@ -103,7 +101,7 @@ func Exists(iface string) (*bool, error) {
 
 // Configure configures a Wireguard interface
 // The interface must exist before calling this method (e.g. call interface.Create() before)
-func Configure(iface string, privateKey string) error {
+func Configure(iface string, privateKey string, port int) error {
 
 	log.Debugf("configuring Wireguard interface %s", iface)
 
@@ -113,12 +111,11 @@ func Configure(iface string, privateKey string) error {
 		return err
 	}
 	fwmark := 0
-	p := WgPort
 	config := wgtypes.Config{
 		PrivateKey:   &key,
 		ReplacePeers: false,
 		FirewallMark: &fwmark,
-		ListenPort:   &p,
+		ListenPort:   &port,
 	}
 
 	return configureDevice(iface, config)
@@ -235,7 +232,7 @@ func RemovePeer(iface string, peerKey string) error {
 	return configureDevice(iface, config)
 }
 
-// Closes the User Space tunnel interface
+// CloseWithUserspace closes the User Space tunnel interface
 func CloseWithUserspace() error {
 	return tunIface.Close()
 }

iface/iface_darwin.go

@@ -40,7 +40,7 @@ func addRoute(iface string, ipNet *net.IPNet) error {
 }
 
 // Closes the tunnel interface
-func Close() error {
+func Close(iFace string) error {
 	name, err := tunIface.Name()
 	if err != nil {
 		return err

iface/iface_linux.go

@@ -1,10 +1,8 @@
 package iface
 
 import (
-	"fmt"
 	log "github.com/sirupsen/logrus"
 	"github.com/vishvananda/netlink"
-	"golang.zx2c4.com/wireguard/wgctrl"
 	"os"
 )
 
@@ -131,34 +129,14 @@ func (w *wgLink) Type() string {
 	return "wireguard"
 }
 
-// Closes the tunnel interface
-func Close() error {
+// Close closes the tunnel interface
+func Close(iFace string) error {
 
 	if tunIface != nil {
 		return CloseWithUserspace()
 	} else {
-		var iface = ""
-		wg, err := wgctrl.New()
-		if err != nil {
-			return err
-		}
-		defer wg.Close()
-		devList, err := wg.Devices()
-		if err != nil {
-			return err
-		}
-		for _, wgDev := range devList {
-			// todo check after move the WgPort constant to the client
-			if wgDev.ListenPort == WgPort {
-				iface = wgDev.Name
-				break
-			}
-		}
-		if iface == "" {
-			return fmt.Errorf("Wireguard Interface not found")
-		}
 		attrs := netlink.NewLinkAttrs()
-		attrs.Name = iface
+		attrs.Name = iFace
 
 		link := wgLink{
 			attrs: &attrs,

iface/iface_test.go

@@ -14,6 +14,7 @@ import (
 const (
 	key        = "0PMI6OkB5JmB+Jj/iWWHekuQRx+bipZirWCWKFXexHc="
 	peerPubKey = "Ok0mC0qlJyXEPKh2UFIpsI2jG0L7LRpC3sLAusSJ5CQ="
+	WgPort     = 51820
 )
 
 func init() {
@@ -29,7 +30,7 @@ func Test_CreateInterface(t *testing.T) {
 		t.Fatal(err)
 	}
 	defer func() {
-		err = Close()
+		err = Close(ifaceName)
 		if err != nil {
 			t.Error(err)
 		}
@@ -44,13 +45,6 @@ func Test_CreateInterface(t *testing.T) {
 			t.Error(err)
 		}
 	}()
-
-	d, err := wg.Device(ifaceName)
-	if err != nil {
-		t.Fatal(err)
-	}
-	// todo move the WgPort constant to the client
-	WgPort = d.ListenPort
 }
 func Test_ConfigureInterface(t *testing.T) {
 	ifaceName := "utun1000"
@@ -60,13 +54,13 @@ func Test_ConfigureInterface(t *testing.T) {
 		t.Fatal(err)
 	}
 	defer func() {
-		err = Close()
+		err = Close(ifaceName)
 		if err != nil {
 			t.Error(err)
 		}
 	}()
 
-	err = Configure(ifaceName, key)
+	err = Configure(ifaceName, key, WgPort)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -99,12 +93,12 @@ func Test_UpdatePeer(t *testing.T) {
 		t.Fatal(err)
 	}
 	defer func() {
-		err = Close()
+		err = Close(ifaceName)
 		if err != nil {
 			t.Error(err)
 		}
 	}()
-	err = Configure(ifaceName, key)
+	err = Configure(ifaceName, key, WgPort)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -151,12 +145,12 @@ func Test_UpdatePeerEndpoint(t *testing.T) {
 		t.Fatal(err)
 	}
 	defer func() {
-		err = Close()
+		err = Close(ifaceName)
 		if err != nil {
 			t.Error(err)
 		}
 	}()
-	err = Configure(ifaceName, key)
+	err = Configure(ifaceName, key, WgPort)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -192,12 +186,12 @@ func Test_RemovePeer(t *testing.T) {
 		t.Fatal(err)
 	}
 	defer func() {
-		err = Close()
+		err = Close(ifaceName)
 		if err != nil {
 			t.Error(err)
 		}
 	}()
-	err = Configure(ifaceName, key)
+	err = Configure(ifaceName, key, WgPort)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -235,13 +229,7 @@ func Test_Close(t *testing.T) {
 		}
 	}()
 
-	d, err := wg.Device(ifaceName)
-	if err != nil {
-		t.Fatal(err)
-	}
-	// todo move the WgPort constant to the client
-	WgPort = d.ListenPort
-	err = Close()
+	err = Close(ifaceName)
 	if err != nil {
 		t.Fatal(err)
 	}

iface/iface_windows.go

@@ -41,6 +41,6 @@ func getUAPI(iface string) (net.Listener, error) {
 }
 
 // Closes the tunnel interface
-func Close() error {
+func Close(iFace string) error {
 	return CloseWithUserspace()
 }