[client] Use WinRT COM for Windows toasts (#6013)

* Use WinRT COM for Windows toasts instead of fyne's PowerShell path

* Quote autostart path and split HKCU registry into per-user component

client/installer.nsis

@@ -200,6 +200,7 @@ Pop $0
 !macroend
 
 Function .onInit
+SetRegView 64
 StrCpy $INSTDIR "${INSTALL_DIR}"
 ReadRegStr $R0 HKLM "Software\Microsoft\Windows\CurrentVersion\Uninstall\$(^NAME)" "UninstallString"
 ${If} $R0 != ""
@@ -214,6 +215,10 @@ ${If} $R0 != ""
 
 ${EndIf}
 FunctionEnd
+
+Function un.onInit
+SetRegView 64
+FunctionEnd
 ######################################################################
 Section -MainProgram
     ${INSTALL_TYPE}
@@ -228,6 +233,7 @@ Section -MainProgram
     !else
         File /r "..\\dist\\netbird_windows_amd64\\"
     !endif
+    File "..\\client\\ui\\assets\\netbird.png"
 SectionEnd
 ######################################################################
 
@@ -247,9 +253,11 @@ WriteRegStr ${REG_ROOT} "${UI_REG_APP_PATH}" "" "$INSTDIR\${UI_APP_EXE}"
 ; Create autostart registry entry based on checkbox
 DetailPrint "Autostart enabled: $AutostartEnabled"
 ${If} $AutostartEnabled == "1"
-    WriteRegStr HKCU "${AUTOSTART_REG_KEY}" "${APP_NAME}" "$INSTDIR\${UI_APP_EXE}.exe"
+    WriteRegStr HKLM "${AUTOSTART_REG_KEY}" "${APP_NAME}" '"$INSTDIR\${UI_APP_EXE}.exe"'
     DetailPrint "Added autostart registry entry: $INSTDIR\${UI_APP_EXE}.exe"
 ${Else}
+    DeleteRegValue HKLM "${AUTOSTART_REG_KEY}" "${APP_NAME}"
+    ; Legacy: pre-HKLM installs wrote to HKCU; clean that up too.
     DeleteRegValue HKCU "${AUTOSTART_REG_KEY}" "${APP_NAME}"
     DetailPrint "Autostart not enabled by user"
 ${EndIf}
@@ -283,6 +291,8 @@ ExecWait `taskkill /im ${UI_APP_EXE}.exe /f`
 
 ; Remove autostart registry entry
 DetailPrint "Removing autostart registry entry if exists..."
+DeleteRegValue HKLM "${AUTOSTART_REG_KEY}" "${APP_NAME}"
+; Legacy: pre-HKLM installs wrote to HKCU; clean that up too.
 DeleteRegValue HKCU "${AUTOSTART_REG_KEY}" "${APP_NAME}"
 
 ; Handle data deletion based on checkbox
@@ -321,6 +331,7 @@ DetailPrint "Removing registry keys..."
 DeleteRegKey ${REG_ROOT} "${REG_APP_PATH}"
 DeleteRegKey ${REG_ROOT} "${UNINSTALL_PATH}"
 DeleteRegKey ${REG_ROOT} "${UI_REG_APP_PATH}"
+DeleteRegKey HKCU "Software\Classes\AppUserModelId\${APP_NAME}"
 
 DetailPrint "Removing application directory from PATH..."
 EnVar::SetHKLM

client/internal/connect.go

@@ -333,6 +333,10 @@ func (c *ConnectClient) run(mobileDependency MobileDependency, runningChan chan
 		c.statusRecorder.MarkSignalConnected()
 
 		relayURLs, token := parseRelayInfo(loginResp)
+		if override, ok := peer.OverrideRelayURLs(); ok {
+			log.Infof("overriding relay URLs from %s: %v", peer.EnvKeyNBHomeRelayServers, override)
+			relayURLs = override
+		}
 		peerConfig := loginResp.GetPeerConfig()
 
 		engineConfig, err := createEngineConfig(myPrivateKey, c.config, peerConfig, logPath)

client/internal/engine.go

@@ -944,7 +944,12 @@ func (e *Engine) handleRelayUpdate(update *mgmProto.RelayConfig) error {
 			return fmt.Errorf("update relay token: %w", err)
 		}
 
-		e.relayManager.UpdateServerURLs(update.Urls)
+		urls := update.Urls
+		if override, ok := peer.OverrideRelayURLs(); ok {
+			log.Infof("overriding relay URLs from %s: %v", peer.EnvKeyNBHomeRelayServers, override)
+			urls = override
+		}
+		e.relayManager.UpdateServerURLs(urls)
 
 		// Just in case the agent started with an MGM server where the relay was disabled but was later enabled.
 		// We can ignore all errors because the guard will manage the reconnection retries.

client/internal/peer/env.go

@@ -7,7 +7,8 @@ import (
 )
 
 const (
-	EnvKeyNBForceRelay = "NB_FORCE_RELAY"
+	EnvKeyNBForceRelay       = "NB_FORCE_RELAY"
+	EnvKeyNBHomeRelayServers = "NB_HOME_RELAY_SERVERS"
 )
 
 func IsForceRelayed() bool {
@@ -16,3 +17,28 @@ func IsForceRelayed() bool {
 	}
 	return strings.EqualFold(os.Getenv(EnvKeyNBForceRelay), "true")
 }
+
+// OverrideRelayURLs returns the relay server URL list set in
+// NB_HOME_RELAY_SERVERS (comma-separated) and a boolean indicating whether
+// the override is active. When the env var is unset, the boolean is false
+// and the caller should keep the list received from the management server.
+// Intended for lab/debug scenarios where a peer must pin to a specific home
+// relay regardless of what management offers.
+func OverrideRelayURLs() ([]string, bool) {
+	raw := os.Getenv(EnvKeyNBHomeRelayServers)
+	if raw == "" {
+		return nil, false
+	}
+	parts := strings.Split(raw, ",")
+	urls := make([]string, 0, len(parts))
+	for _, p := range parts {
+		p = strings.TrimSpace(p)
+		if p != "" {
+			urls = append(urls, p)
+		}
+	}
+	if len(urls) == 0 {
+		return nil, false
+	}
+	return urls, true
+}

client/netbird.wxs

@@ -18,10 +18,17 @@
 				<Component Id="NetbirdFiles" Guid="db3165de-cc6e-4922-8396-9d892950e23e" Bitness="always64">
 					<File ProcessorArchitecture="$(var.ProcessorArchitecture)" Source=".\dist\netbird_windows_$(var.ArchSuffix)\netbird.exe" KeyPath="yes" />
 					<File ProcessorArchitecture="$(var.ProcessorArchitecture)" Source=".\dist\netbird_windows_$(var.ArchSuffix)\netbird-ui.exe">
-						<Shortcut Id="NetbirdDesktopShortcut" Directory="DesktopFolder" Name="NetBird" WorkingDirectory="NetbirdInstallDir" Icon="NetbirdIcon" />
+						<Shortcut Id="NetbirdDesktopShortcut" Directory="DesktopFolder" Name="NetBird" WorkingDirectory="NetbirdInstallDir" Icon="NetbirdIcon">
-						<Shortcut Id="NetbirdStartMenuShortcut" Directory="StartMenuFolder" Name="NetBird" WorkingDirectory="NetbirdInstallDir" Icon="NetbirdIcon" />
+							<ShortcutProperty Key="System.AppUserModel.ID" Value="NetBird" />
+							<ShortcutProperty Key="System.AppUserModel.ToastActivatorCLSID" Value="{0E1B4DE7-E148-432B-9814-544F941826EC}" />
+						</Shortcut>
+						<Shortcut Id="NetbirdStartMenuShortcut" Directory="StartMenuFolder" Name="NetBird" WorkingDirectory="NetbirdInstallDir" Icon="NetbirdIcon">
+							<ShortcutProperty Key="System.AppUserModel.ID" Value="NetBird" />
+							<ShortcutProperty Key="System.AppUserModel.ToastActivatorCLSID" Value="{0E1B4DE7-E148-432B-9814-544F941826EC}" />
+						</Shortcut>
 					</File>
 					<File ProcessorArchitecture="$(var.ProcessorArchitecture)" Source=".\dist\netbird_windows_$(var.ArchSuffix)\wintun.dll" />
+					<File Id="NetbirdToastIcon" Name="netbird.png" Source=".\client\ui\assets\netbird.png" />
 					<?if $(var.ArchSuffix) = "amd64" ?>
 					<File ProcessorArchitecture="$(var.ProcessorArchitecture)" Source=".\dist\netbird_windows_$(var.ArchSuffix)\opengl32.dll" />
 					<?endif ?>
@@ -46,8 +53,19 @@
 			</Directory>
 		</StandardDirectory>
 
+		<!-- Per-user component: HKCU keypath (auto GUID via "*"), separate from
+		     the per-machine NetbirdFiles component to satisfy ICE57. -->
+		<StandardDirectory Id="ProgramMenuFolder">
+			<Component Id="NetbirdAumidRegistry" Guid="*">
+				<RegistryKey Root="HKCU" Key="Software\Classes\AppUserModelId\NetBird" ForceDeleteOnUninstall="yes">
+					<RegistryValue Name="InstalledByMSI" Type="integer" Value="1" KeyPath="yes" />
+				</RegistryKey>
+			</Component>
+		</StandardDirectory>
+
 		<ComponentGroup Id="NetbirdFilesComponent">
 			<ComponentRef Id="NetbirdFiles" />
+			<ComponentRef Id="NetbirdAumidRegistry" />
 		</ComponentGroup>
 
 		<util:CloseApplication Id="CloseNetBird" CloseMessage="no" Target="netbird.exe" RebootPrompt="no" />

client/ui/client_ui.go

@@ -42,6 +42,7 @@ import (
 	"github.com/netbirdio/netbird/client/proto"
 	"github.com/netbirdio/netbird/client/ui/desktop"
 	"github.com/netbirdio/netbird/client/ui/event"
+	"github.com/netbirdio/netbird/client/ui/notifier"
 	"github.com/netbirdio/netbird/client/ui/process"
 	"github.com/netbirdio/netbird/util"
 
@@ -260,6 +261,7 @@ type serviceClient struct {
 
 	// application with main windows.
 	app                  fyne.App
+	notifier             notifier.Notifier
 	wSettings            fyne.Window
 	showAdvancedSettings bool
 	sendNotification     bool
@@ -364,6 +366,7 @@ func newServiceClient(args *newServiceClientArgs) *serviceClient {
 		cancel:           cancel,
 		addr:             args.addr,
 		app:              args.app,
+		notifier:         notifier.New(args.app),
 		logFile:          args.logFile,
 		sendNotification: false,
 
@@ -892,7 +895,7 @@ func (s *serviceClient) updateStatus() error {
 		if err != nil {
 			log.Errorf("get service status: %v", err)
 			if s.connected {
-				s.app.SendNotification(fyne.NewNotification("Error", "Connection to service lost"))
+				s.notifier.Send("Error", "Connection to service lost")
 			}
 			s.setDisconnectedStatus()
 			return err
@@ -1109,7 +1112,7 @@ func (s *serviceClient) onTrayReady() {
 		}
 	}()
 
-	s.eventManager = event.NewManager(s.app, s.addr)
+	s.eventManager = event.NewManager(s.notifier, s.addr)
 	s.eventManager.SetNotificationsEnabled(s.mNotifications.Checked())
 	s.eventManager.AddHandler(func(event *proto.SystemEvent) {
 		if event.Category == proto.SystemEvent_SYSTEM {
@@ -1548,7 +1551,7 @@ func (s *serviceClient) onUpdateAvailable(newVersion string, enforced bool) {
 
 	if enforced && s.lastNotifiedVersion != newVersion {
 		s.lastNotifiedVersion = newVersion
-		s.app.SendNotification(fyne.NewNotification("Update available", "A new version "+newVersion+" is ready to install"))
+		s.notifier.Send("Update available", "A new version "+newVersion+" is ready to install")
 	}
 }
 

client/ui/event/event.go

@@ -8,7 +8,6 @@ import (
 	"sync"
 	"time"
 
-	"fyne.io/fyne/v2"
 	"github.com/cenkalti/backoff/v4"
 	log "github.com/sirupsen/logrus"
 	"google.golang.org/grpc"
@@ -18,11 +17,17 @@ import (
 	"github.com/netbirdio/netbird/client/ui/desktop"
 )
 
+// Notifier sends desktop notifications. Defined here so the event package
+// does not depend on fyne or the platform-specific notifier implementation.
+type Notifier interface {
+	Send(title, body string)
+}
+
 type Handler func(*proto.SystemEvent)
 
 type Manager struct {
-	app  fyne.App
+	notifier Notifier
-	addr string
+	addr     string
 
 	mu       sync.Mutex
 	ctx      context.Context
@@ -31,10 +36,10 @@ type Manager struct {
 	handlers []Handler
 }
 
-func NewManager(app fyne.App, addr string) *Manager {
+func NewManager(notifier Notifier, addr string) *Manager {
 	return &Manager{
-		app:  app,
+		notifier: notifier,
-		addr: addr,
+		addr:     addr,
 	}
 }
 
@@ -114,7 +119,7 @@ func (e *Manager) handleEvent(event *proto.SystemEvent) {
 		if id != "" {
 			body += fmt.Sprintf(" ID: %s", id)
 		}
-		e.app.SendNotification(fyne.NewNotification(title, body))
+		e.notifier.Send(title, body)
 	}
 
 	for _, handler := range handlers {

client/ui/event_handler.go

@@ -9,7 +9,6 @@ import (
 	"os"
 	"os/exec"
 
-	"fyne.io/fyne/v2"
 	"fyne.io/systray"
 	log "github.com/sirupsen/logrus"
 	"google.golang.org/grpc/codes"
@@ -87,7 +86,7 @@ func (h *eventHandler) handleConnectClick() {
 			if errors.Is(err, context.Canceled) || (ok && st.Code() == codes.Canceled) {
 				log.Debugf("connect operation cancelled by user")
 			} else {
-				h.client.app.SendNotification(fyne.NewNotification("Error", "Failed to connect"))
+				h.client.notifier.Send("Error", "Failed to connect")
 				log.Errorf("connect failed: %v", err)
 			}
 		}
@@ -112,7 +111,7 @@ func (h *eventHandler) handleDisconnectClick() {
 		if err := h.client.menuDownClick(); err != nil {
 			st, ok := status.FromError(err)
 			if !errors.Is(err, context.Canceled) && !(ok && st.Code() == codes.Canceled) {
-				h.client.app.SendNotification(fyne.NewNotification("Error", "Failed to disconnect"))
+				h.client.notifier.Send("Error", "Failed to disconnect")
 				log.Errorf("disconnect failed: %v", err)
 			} else {
 				log.Debugf("disconnect cancelled or already disconnecting")
@@ -130,7 +129,7 @@ func (h *eventHandler) handleAllowSSHClick() {
 	if err := h.updateConfigWithErr(); err != nil {
 		h.toggleCheckbox(h.client.mAllowSSH) // revert checkbox state on error
 		log.Errorf("failed to update config: %v", err)
-		h.client.app.SendNotification(fyne.NewNotification("Error", "Failed to update SSH settings"))
+		h.client.notifier.Send("Error", "Failed to update SSH settings")
 	}
 
 }
@@ -140,7 +139,7 @@ func (h *eventHandler) handleAutoConnectClick() {
 	if err := h.updateConfigWithErr(); err != nil {
 		h.toggleCheckbox(h.client.mAutoConnect) // revert checkbox state on error
 		log.Errorf("failed to update config: %v", err)
-		h.client.app.SendNotification(fyne.NewNotification("Error", "Failed to update auto-connect settings"))
+		h.client.notifier.Send("Error", "Failed to update auto-connect settings")
 	}
 }
 
@@ -149,7 +148,7 @@ func (h *eventHandler) handleRosenpassClick() {
 	if err := h.updateConfigWithErr(); err != nil {
 		h.toggleCheckbox(h.client.mEnableRosenpass) // revert checkbox state on error
 		log.Errorf("failed to update config: %v", err)
-		h.client.app.SendNotification(fyne.NewNotification("Error", "Failed to update Rosenpass settings"))
+		h.client.notifier.Send("Error", "Failed to update Rosenpass settings")
 	}
 }
 
@@ -158,7 +157,7 @@ func (h *eventHandler) handleLazyConnectionClick() {
 	if err := h.updateConfigWithErr(); err != nil {
 		h.toggleCheckbox(h.client.mLazyConnEnabled) // revert checkbox state on error
 		log.Errorf("failed to update config: %v", err)
-		h.client.app.SendNotification(fyne.NewNotification("Error", "Failed to update lazy connection settings"))
+		h.client.notifier.Send("Error", "Failed to update lazy connection settings")
 	}
 }
 
@@ -167,7 +166,7 @@ func (h *eventHandler) handleBlockInboundClick() {
 	if err := h.updateConfigWithErr(); err != nil {
 		h.toggleCheckbox(h.client.mBlockInbound) // revert checkbox state on error
 		log.Errorf("failed to update config: %v", err)
-		h.client.app.SendNotification(fyne.NewNotification("Error", "Failed to update block inbound settings"))
+		h.client.notifier.Send("Error", "Failed to update block inbound settings")
 	}
 }
 
@@ -176,7 +175,7 @@ func (h *eventHandler) handleNotificationsClick() {
 	if err := h.updateConfigWithErr(); err != nil {
 		h.toggleCheckbox(h.client.mNotifications) // revert checkbox state on error
 		log.Errorf("failed to update config: %v", err)
-		h.client.app.SendNotification(fyne.NewNotification("Error", "Failed to update notifications settings"))
+		h.client.notifier.Send("Error", "Failed to update notifications settings")
 	} else if h.client.eventManager != nil {
 		h.client.eventManager.SetNotificationsEnabled(h.client.mNotifications.Checked())
 	}

client/ui/notifier/notifier.go

@@ -0,0 +1,27 @@
+// Package notifier sends desktop notifications. On Windows it uses the WinRT
+// COM API directly via go-toast/v2 to avoid the PowerShell window flash that
+// fyne's default implementation produces. On other platforms it delegates to
+// fyne.
+package notifier
+
+import "fyne.io/fyne/v2"
+
+// Notifier sends desktop notifications.
+type Notifier interface {
+	Send(title, body string)
+}
+
+// New returns a platform-specific Notifier. The fyne app is used as the
+// fallback notifier on platforms where no native implementation is wired up,
+// and on Windows when the COM path fails to initialize.
+func New(app fyne.App) Notifier {
+	return newNotifier(app)
+}
+
+type fyneNotifier struct {
+	app fyne.App
+}
+
+func (f *fyneNotifier) Send(title, body string) {
+	f.app.SendNotification(fyne.NewNotification(title, body))
+}

client/ui/notifier/notifier_other.go

@@ -0,0 +1,9 @@
+//go:build !windows
+
+package notifier
+
+import "fyne.io/fyne/v2"
+
+func newNotifier(app fyne.App) Notifier {
+	return &fyneNotifier{app: app}
+}

client/ui/notifier/notifier_windows.go

@@ -0,0 +1,88 @@
+package notifier
+
+import (
+	"os"
+	"path/filepath"
+	"sync"
+
+	"fyne.io/fyne/v2"
+	toast "git.sr.ht/~jackmordaunt/go-toast/v2"
+	"git.sr.ht/~jackmordaunt/go-toast/v2/wintoast"
+	log "github.com/sirupsen/logrus"
+)
+
+const (
+	// appID is the AppUserModelID shown in the Windows Action Center. It
+	// must match the System.AppUserModel.ID property set on the Start Menu
+	// shortcut by the MSI (see client/netbird.wxs); otherwise Windows
+	// groups toasts under a separate, unbranded entry.
+	appID = "NetBird"
+
+	// appGUID identifies the COM activation callback class. Generated once
+	// for NetBird; do not change without coordinating an installer bump,
+	// since old registry entries pointing at the previous GUID would orphan.
+	appGUID = "{0E1B4DE7-E148-432B-9814-544F941826EC}"
+)
+
+type comNotifier struct {
+	fallback *fyneNotifier
+	ready    bool
+	iconPath string
+}
+
+var (
+	initOnce sync.Once
+	initErr  error
+)
+
+func newNotifier(app fyne.App) Notifier {
+	n := &comNotifier{
+		fallback: &fyneNotifier{app: app},
+		iconPath: resolveIcon(),
+	}
+	initOnce.Do(func() {
+		initErr = wintoast.SetAppData(wintoast.AppData{
+			AppID:    appID,
+			GUID:     appGUID,
+			IconPath: n.iconPath,
+		})
+	})
+	if initErr != nil {
+		log.Warnf("toast: register app data failed, falling back to fyne notifications: %v", initErr)
+		return n.fallback
+	}
+	n.ready = true
+	return n
+}
+
+func (n *comNotifier) Send(title, body string) {
+	if !n.ready {
+		n.fallback.Send(title, body)
+		return
+	}
+	notification := toast.Notification{
+		AppID: appID,
+		Title: title,
+		Body:  body,
+		Icon:  n.iconPath,
+	}
+	if err := notification.Push(); err != nil {
+		log.Warnf("toast: push failed, using fyne fallback: %v", err)
+		n.fallback.Send(title, body)
+	}
+}
+
+// resolveIcon returns an absolute path to the toast icon, or an empty string
+// when no icon can be located. Windows requires a PNG/JPG for the
+// AppUserModelId IconUri registry value; .ico is silently ignored.
+func resolveIcon() string {
+	exe, err := os.Executable()
+	if err != nil {
+		return ""
+	}
+	candidate := filepath.Join(filepath.Dir(exe), "netbird.png")
+	if _, err := os.Stat(candidate); err == nil {
+		return candidate
+	}
+	return ""
+}

client/ui/profile.go

@@ -548,7 +548,7 @@ func (p *profileMenu) refresh() {
 					if err != nil {
 						log.Errorf("failed to switch profile: %v", err)
 						// show  notification dialog
-						p.app.SendNotification(fyne.NewNotification("Error", "Failed to switch profile"))
+						p.serviceClient.notifier.Send("Error", "Failed to switch profile")
 						return
 					}
 
@@ -628,9 +628,9 @@ func (p *profileMenu) refresh() {
 				}
 				if err := p.eventHandler.logout(p.ctx); err != nil {
 					log.Errorf("logout failed: %v", err)
-					p.app.SendNotification(fyne.NewNotification("Error", "Failed to deregister"))
+					p.serviceClient.notifier.Send("Error", "Failed to deregister")
 				} else {
-					p.app.SendNotification(fyne.NewNotification("Success", "Deregistered successfully"))
+					p.serviceClient.notifier.Send("Success", "Deregistered successfully")
 				}
 			}
 		}

go.mod

@@ -30,6 +30,7 @@ require (
 require (
 	fyne.io/fyne/v2 v2.7.0
 	fyne.io/systray v1.12.1-0.20260116214250-81f8e1a496f9
+	git.sr.ht/~jackmordaunt/go-toast/v2 v2.0.3
 	github.com/awnumar/memguard v0.23.0
 	github.com/aws/aws-sdk-go-v2 v1.38.3
 	github.com/aws/aws-sdk-go-v2/config v1.31.6

go.sum

@@ -15,6 +15,8 @@ fyne.io/fyne/v2 v2.7.0 h1:GvZSpE3X0liU/fqstInVvRsaboIVpIWQ4/sfjDGIGGQ=
 fyne.io/fyne/v2 v2.7.0/go.mod h1:xClVlrhxl7D+LT+BWYmcrW4Nf+dJTvkhnPgji7spAwE=
 fyne.io/systray v1.12.1-0.20260116214250-81f8e1a496f9 h1:829+77I4TaMrcg9B3wf+gHhdSgoCVEgH2czlPXPbfj4=
 fyne.io/systray v1.12.1-0.20260116214250-81f8e1a496f9/go.mod h1:RVwqP9nYMo7h5zViCBHri2FgjXF7H2cub7MAq4NSoLs=
+git.sr.ht/~jackmordaunt/go-toast/v2 v2.0.3 h1:N3IGoHHp9pb6mj1cbXbuaSXV/UMKwmbKLf53nQmtqMA=
+git.sr.ht/~jackmordaunt/go-toast/v2 v2.0.3/go.mod h1:QtOLZGz8olr4qH2vWK0QH0w0O4T9fEIjMuWpKUsH7nc=
 github.com/AdaLogics/go-fuzz-headers v0.0.0-20230811130428-ced1acdcaa24 h1:bvDV9vkmnHYOMsOr4WLk+Vo07yKIzd94sVoIqshQ4bU=
 github.com/AdaLogics/go-fuzz-headers v0.0.0-20230811130428-ced1acdcaa24/go.mod h1:8o94RPi1/7XTJvwPpRSzSUedZrtlirdB3r9Z20bi2f8=
 github.com/AppsFlyer/go-sundheit v0.6.0 h1:d2hBvCjBSb2lUsEWGfPigr4MCOt04sxB+Rppl0yUMSk=

idp/dex/config.go

@@ -193,7 +193,7 @@ func (c *Connector) ToStorageConnector() (storage.Connector, error) {
 // are stored with types that Dex can open.
 func mapConnectorToDex(connType string, config map[string]interface{}) (string, map[string]interface{}) {
 	switch connType {
-	case "oidc", "zitadel", "entra", "okta", "pocketid", "authentik", "keycloak":
+	case "oidc", "zitadel", "entra", "okta", "pocketid", "authentik", "keycloak", "adfs":
 		return "oidc", applyOIDCDefaults(connType, config)
 	default:
 		return connType, config
@@ -218,6 +218,8 @@ func applyOIDCDefaults(connType string, config map[string]interface{}) map[strin
 		setDefault(augmented, "claimMapping", map[string]string{"email": "preferred_username"})
 	case "okta", "pocketid":
 		augmented["scopes"] = []string{"openid", "profile", "email", "groups"}
+	case "adfs":
+		augmented["scopes"] = []string{"openid", "profile", "email", "allatclaims"}
 	}
 
 	return augmented

idp/dex/connector.go

@@ -168,7 +168,7 @@ func (p *Provider) buildStorageConnector(cfg *ConnectorConfig) (storage.Connecto
 	var err error
 
 	switch cfg.Type {
-	case "oidc", "zitadel", "entra", "okta", "pocketid", "authentik", "keycloak":
+	case "oidc", "zitadel", "entra", "okta", "pocketid", "authentik", "keycloak", "adfs":
 		dexType = "oidc"
 		configData, err = buildOIDCConnectorConfig(cfg, redirectURI)
 	case "google":
@@ -220,6 +220,8 @@ func buildOIDCConnectorConfig(cfg *ConnectorConfig, redirectURI string) ([]byte,
 		oidcConfig["scopes"] = []string{"openid", "profile", "email", "groups"}
 	case "pocketid":
 		oidcConfig["scopes"] = []string{"openid", "profile", "email", "groups"}
+	case "adfs":
+		oidcConfig["scopes"] = []string{"openid", "profile", "email", "allatclaims"}
 	}
 	return encodeConnectorConfig(oidcConfig)
 }
@@ -283,7 +285,7 @@ func inferIdentityProviderType(dexType, connectorID string, _ map[string]interfa
 // inferOIDCProviderType infers the specific OIDC provider from connector ID
 func inferOIDCProviderType(connectorID string) string {
 	connectorIDLower := strings.ToLower(connectorID)
-	for _, provider := range []string{"pocketid", "zitadel", "entra", "okta", "authentik", "keycloak"} {
+	for _, provider := range []string{"pocketid", "zitadel", "entra", "okta", "authentik", "keycloak", "adfs"} {
 		if strings.Contains(connectorIDLower, provider) {
 			return provider
 		}

infrastructure_files/getting-started.sh

@@ -231,7 +231,20 @@ get_upstream_host() {
 
 wait_management_proxy() {
   local proxy_container="${1:-traefik}"
+  local use_docker_logs=false
   set +e
+
+  if [[ "$proxy_container" == "detect-traefik" ]]; then
+    proxy_container=$(docker ps --format "{{.ID}}\t{{.Image}}\t{{.Ports}}" \
+    | awk -F'\t' '$2 ~ /traefik/ && $3 ~ /:(80|443)->/ {print $1; exit}')
+
+    if [[ -z "$proxy_container" ]]; then
+      echo "Warning: could not auto-detect Traefik container, log output will be skipped on timeout." > /dev/stderr
+    else
+      use_docker_logs=true
+    fi
+  fi
+
   echo -n "Waiting for NetBird server to become ready"
   counter=1
   while true; do
@@ -242,7 +255,13 @@ wait_management_proxy() {
     if [[ $counter -eq 60 ]]; then
       echo ""
       echo "Taking too long. Checking logs..."
-      $DOCKER_COMPOSE_COMMAND logs --tail=20 "$proxy_container"
+      if [[ -n "$proxy_container" ]]; then
+        if [[ "$use_docker_logs" == "true" ]]; then
+          docker logs --tail=20 "$proxy_container"
+        else
+          $DOCKER_COMPOSE_COMMAND logs --tail=20 "$proxy_container"
+        fi
+      fi
       $DOCKER_COMPOSE_COMMAND logs --tail=20 netbird-server
     fi
     echo -n " ."
@@ -518,7 +537,7 @@ start_services_and_show_instructions() {
     $DOCKER_COMPOSE_COMMAND up -d
 
     sleep 3
-    wait_management_direct
+    wait_management_proxy detect-traefik
 
     echo -e "$MSG_DONE"
     print_post_setup_instructions

management/server/identity_provider.go

@@ -274,7 +274,7 @@ func identityProviderToConnectorConfig(idpConfig *types.IdentityProvider) *dex.C
 }
 
 // generateIdentityProviderID generates a unique ID for an identity provider.
-// For specific provider types (okta, zitadel, entra, google, pocketid, microsoft),
+// For specific provider types (okta, zitadel, entra, google, pocketid, microsoft, adfs),
 // the ID is prefixed with the type name. Generic OIDC providers get no prefix.
 func generateIdentityProviderID(idpType types.IdentityProviderType) string {
 	id := xid.New().String()
@@ -296,6 +296,8 @@ func generateIdentityProviderID(idpType types.IdentityProviderType) string {
 		return "authentik-" + id
 	case types.IdentityProviderTypeKeycloak:
 		return "keycloak-" + id
+	case types.IdentityProviderTypeADFS:
+		return "adfs-" + id
 	default:
 		// Generic OIDC - no prefix
 		return id

management/server/peer.go

@@ -33,8 +33,8 @@ import (
 
 const remoteJobsMinVer = "0.64.0"
 
-// GetPeers returns a list of peers under the given account filtering out peers that do not belong to a user if
+// GetPeers returns peers visible to the user within an account.
-// the current user is not an admin.
+// Users with "peers:read" see all peers. Otherwise, users see only their own peers, or none if restricted by account settings.
 func (am *DefaultAccountManager) GetPeers(ctx context.Context, accountID, userID, nameFilter, ipFilter string) ([]*nbpeer.Peer, error) {
 	user, err := am.Store.GetUserByUserID(ctx, store.LockingStrengthNone, userID)
 	if err != nil {
@@ -46,14 +46,8 @@ func (am *DefaultAccountManager) GetPeers(ctx context.Context, accountID, userID
 		return nil, status.NewPermissionValidationError(err)
 	}
 
-	accountPeers, err := am.Store.GetAccountPeers(ctx, store.LockingStrengthNone, accountID, nameFilter, ipFilter)
-	if err != nil {
-		return nil, err
-	}
-
-	// @note if the user has permission to read peers it shows all account peers
 	if allowed {
-		return accountPeers, nil
+		return am.Store.GetAccountPeers(ctx, store.LockingStrengthNone, accountID, nameFilter, ipFilter)
 	}
 
 	settings, err := am.Store.GetAccountSettings(ctx, store.LockingStrengthNone, accountID)
@@ -65,41 +59,7 @@ func (am *DefaultAccountManager) GetPeers(ctx context.Context, accountID, userID
 		return []*nbpeer.Peer{}, nil
 	}
 
-	// @note if it does not have permission read peers then only display it's own peers
+	return am.Store.GetUserPeers(ctx, store.LockingStrengthNone, accountID, userID)
-	peers := make([]*nbpeer.Peer, 0)
-	peersMap := make(map[string]*nbpeer.Peer)
-
-	for _, peer := range accountPeers {
-		if user.Id != peer.UserID {
-			continue
-		}
-		peers = append(peers, peer)
-		peersMap[peer.ID] = peer
-	}
-
-	return am.getUserAccessiblePeers(ctx, accountID, peersMap, peers)
-}
-
-func (am *DefaultAccountManager) getUserAccessiblePeers(ctx context.Context, accountID string, peersMap map[string]*nbpeer.Peer, peers []*nbpeer.Peer) ([]*nbpeer.Peer, error) {
-	account, err := am.requestBuffer.GetAccountWithBackpressure(ctx, accountID)
-	if err != nil {
-		return nil, err
-	}
-
-	approvedPeersMap, err := am.integratedPeerValidator.GetValidatedPeers(ctx, accountID, maps.Values(account.Groups), maps.Values(account.Peers), account.Settings.Extra)
-	if err != nil {
-		return nil, err
-	}
-
-	// fetch all the peers that have access to the user's peers
-	for _, peer := range peers {
-		aclPeers, _, _, _ := account.GetPeerConnectionResources(ctx, peer, approvedPeersMap, account.GetActiveGroupUsers())
-		for _, p := range aclPeers {
-			peersMap[p.ID] = p
-		}
-	}
-
-	return maps.Values(peersMap), nil
 }
 
 // MarkPeerConnected marks peer as connected (true) or disconnected (false)
@@ -1230,7 +1190,8 @@ func peerLoginExpired(ctx context.Context, peer *nbpeer.Peer, settings *types.Se
 	return false
 }
 
-// GetPeer for a given accountID, peerID and userID error if not found.
+// GetPeer returns a peer visible to the user within an account.
+// Users with "peers:read" permission can access any peer. Otherwise, users can access only their own peer.
 func (am *DefaultAccountManager) GetPeer(ctx context.Context, accountID, peerID, userID string) (*nbpeer.Peer, error) {
 	peer, err := am.Store.GetPeerByID(ctx, store.LockingStrengthNone, accountID, peerID)
 	if err != nil {
@@ -1255,36 +1216,6 @@ func (am *DefaultAccountManager) GetPeer(ctx context.Context, accountID, peerID,
 		return peer, nil
 	}
 
-	return am.checkIfUserOwnsPeer(ctx, accountID, userID, peer)
-}
-
-func (am *DefaultAccountManager) checkIfUserOwnsPeer(ctx context.Context, accountID, userID string, peer *nbpeer.Peer) (*nbpeer.Peer, error) {
-	account, err := am.requestBuffer.GetAccountWithBackpressure(ctx, accountID)
-	if err != nil {
-		return nil, err
-	}
-
-	approvedPeersMap, err := am.integratedPeerValidator.GetValidatedPeers(ctx, accountID, maps.Values(account.Groups), maps.Values(account.Peers), account.Settings.Extra)
-	if err != nil {
-		return nil, err
-	}
-
-	// it is also possible that user doesn't own the peer but some of his peers have access to it,
-	// this is a valid case, show the peer as well.
-	userPeers, err := am.Store.GetUserPeers(ctx, store.LockingStrengthNone, accountID, userID)
-	if err != nil {
-		return nil, err
-	}
-
-	for _, p := range userPeers {
-		aclPeers, _, _, _ := account.GetPeerConnectionResources(ctx, p, approvedPeersMap, account.GetActiveGroupUsers())
-		for _, aclPeer := range aclPeers {
-			if aclPeer.ID == peer.ID {
-				return peer, nil
-			}
-		}
-	}
-
 	return nil, status.Errorf(status.Internal, "user %s has no access to peer %s under account %s", userID, peer.ID, accountID)
 }
 

management/server/peer_test.go

@@ -559,25 +559,9 @@ func TestDefaultAccountManager_GetPeer(t *testing.T) {
 	}
 	assert.NotNil(t, peer)
 
-	// the user can see peer2 because peer1 of the user has access to peer2 due to the All group and the default rule 0 all-to-all access
+	// the user can NOT see peer2 because it is not owned by them.
-	peer, err = manager.GetPeer(context.Background(), accountID, peer2.ID, someUser)
+	// Regular users only see peers they directly own.
-	if err != nil {
+	_, err = manager.GetPeer(context.Background(), accountID, peer2.ID, someUser)
-		t.Fatal(err)
-		return
-	}
-	assert.NotNil(t, peer)
-
-	// delete the all-to-all policy so that user's peer1 has no access to peer2
-	for _, policy := range account.Policies {
-		err = manager.DeletePolicy(context.Background(), accountID, policy.ID, adminUser)
-		if err != nil {
-			t.Fatal(err)
-			return
-		}
-	}
-
-	// at this point the user can't see the details of peer2
-	peer, err = manager.GetPeer(context.Background(), accountID, peer2.ID, someUser) //nolint
 	assert.Error(t, err)
 
 	// admin users can always access all the peers

management/server/types/identity_provider.go

@@ -39,6 +39,8 @@ const (
 	IdentityProviderTypeAuthentik IdentityProviderType = "authentik"
 	// IdentityProviderTypeKeycloak is the Keycloak identity provider
 	IdentityProviderTypeKeycloak IdentityProviderType = "keycloak"
+	// IdentityProviderTypeADFS is the Microsoft AD FS identity provider
+	IdentityProviderTypeADFS IdentityProviderType = "adfs"
 )
 
 // IdentityProvider represents an identity provider configuration
@@ -112,7 +114,8 @@ func (t IdentityProviderType) IsValid() bool {
 	switch t {
 	case IdentityProviderTypeOIDC, IdentityProviderTypeZitadel, IdentityProviderTypeEntra,
 		IdentityProviderTypeGoogle, IdentityProviderTypeOkta, IdentityProviderTypePocketID,
-		IdentityProviderTypeMicrosoft, IdentityProviderTypeAuthentik, IdentityProviderTypeKeycloak:
+		IdentityProviderTypeMicrosoft, IdentityProviderTypeAuthentik, IdentityProviderTypeKeycloak,
+		IdentityProviderTypeADFS:
 		return true
 	}
 	return false

shared/auth/jwt/extractor.go

@@ -146,7 +146,11 @@ func (c *ClaimsExtractor) ToGroups(token *jwt.Token, claimName string) []string
 	userJWTGroups := make([]string, 0)
 
 	if claim, ok := claims[claimName]; ok {
-		if claimGroups, ok := claim.([]interface{}); ok {
+		switch claimGroups := claim.(type) {
+		case string:
+			// Some IdPs emit a single group claim as a string instead of an array.
+			userJWTGroups = append(userJWTGroups, claimGroups)
+		case []any:
 			for _, g := range claimGroups {
 				if group, ok := g.(string); ok {
 					userJWTGroups = append(userJWTGroups, group)
@@ -154,9 +158,11 @@ func (c *ClaimsExtractor) ToGroups(token *jwt.Token, claimName string) []string
 					log.Debugf("JWT claim %q contains a non-string group (type: %T): %v", claimName, g, g)
 				}
 			}
+		default:
+			log.Debugf("JWT claim %q is not a string or string array (type: %T): %v", claimName, claim, claim)
 		}
 	} else {
-		log.Debugf("JWT claim %q is not a string array", claimName)
+		log.Debugf("JWT claim %q is missing", claimName)
 	}
 
 	return userJWTGroups

shared/auth/jwt/extractor_test.go

@@ -249,6 +249,15 @@ func TestClaimsExtractor_ToGroups(t *testing.T) {
 			groupClaimName: "groups",
 			expectedGroups: []string{},
 		},
+		{
+			name: "extracts single group string from claim",
+			claims: jwt.MapClaims{
+				"sub":    "user-123",
+				"groups": "admin",
+			},
+			groupClaimName: "groups",
+			expectedGroups: []string{"admin"},
+		},
 		{
 			name: "handles custom claim name",
 			claims: jwt.MapClaims{

shared/management/client/grpc.go

@@ -252,21 +252,19 @@ func (c *GrpcClient) handleJobStream(
 					c.notifyDisconnected(err)
 					return backoff.Permanent(err) // unrecoverable error, propagate to the upper layer
 				case codes.Canceled:
-					log.Debugf("management connection context has been canceled, this usually indicates shutdown")
+					log.Debugf("job stream context has been canceled, this usually indicates shutdown")
 					return err
 				case codes.Unimplemented:
 					log.Warn("Job feature is not supported by the current management server version. " +
 						"Please update the management service to use this feature.")
 					return nil
 				default:
-					c.notifyDisconnected(err)
+					log.Warnf("job stream disconnected, will retry silently. Reason: %v", err)
-					log.Warnf("disconnected from the Management service but will retry silently. Reason: %v", err)
 					return err
 				}
 			} else {
 				// non-gRPC error
-				c.notifyDisconnected(err)
+				log.Warnf("job stream disconnected, will retry silently. Reason: %v", err)
-				log.Warnf("disconnected from the Management service but will retry silently. Reason: %v", err)
 				return err
 			}
 		}

shared/management/http/api/openapi.yml

@@ -2917,6 +2917,7 @@ components:
         - okta
         - pocketid
         - microsoft
+        - adfs
       example: oidc
     IdentityProvider:
       type: object

shared/management/http/api/types.gen.go

@@ -518,6 +518,7 @@ const (
 	IdentityProviderTypeOkta      IdentityProviderType = "okta"
 	IdentityProviderTypePocketid  IdentityProviderType = "pocketid"
 	IdentityProviderTypeZitadel   IdentityProviderType = "zitadel"
+	IdentityProviderTypeAdfs      IdentityProviderType = "adfs"
 )
 
 // Valid indicates whether the value is a known member of the IdentityProviderType enum.
@@ -537,6 +538,8 @@ func (e IdentityProviderType) Valid() bool {
 		return true
 	case IdentityProviderTypeZitadel:
 		return true
+	case IdentityProviderTypeAdfs:
+		return true
 	default:
 		return false
 	}

shared/relay/client/guard.go

@@ -8,10 +8,7 @@ import (
 	log "github.com/sirupsen/logrus"
 )
 
-const (
+const defaultMaxBackoffInterval = 60 * time.Second
-	// TODO: make it configurable, the manager should validate all configurable parameters
-	reconnectingTimeout = 60 * time.Second
-)
 
 // Guard manage the reconnection tries to the Relay server in case of disconnection event.
 type Guard struct {
@@ -19,14 +16,23 @@ type Guard struct {
 	OnNewRelayClient chan *Client
 	OnReconnected    chan struct{}
 	serverPicker     *ServerPicker
+
+	// maxBackoffInterval caps the exponential backoff between reconnect
+	// attempts.
+	maxBackoffInterval time.Duration
 }
 
-// NewGuard creates a new guard for the relay client.
+// NewGuard creates a new guard for the relay client. A non-positive
-func NewGuard(sp *ServerPicker) *Guard {
+// maxBackoffInterval falls back to defaultMaxBackoffInterval.
+func NewGuard(sp *ServerPicker, maxBackoffInterval time.Duration) *Guard {
+	if maxBackoffInterval <= 0 {
+		maxBackoffInterval = defaultMaxBackoffInterval
+	}
 	g := &Guard{
-		OnNewRelayClient: make(chan *Client, 1),
+		OnNewRelayClient:   make(chan *Client, 1),
-		OnReconnected:    make(chan struct{}, 1),
+		OnReconnected:      make(chan struct{}, 1),
-		serverPicker:     sp,
+		serverPicker:       sp,
+		maxBackoffInterval: maxBackoffInterval,
 	}
 	return g
 }
@@ -49,7 +55,7 @@ func (g *Guard) StartReconnectTrys(ctx context.Context, relayClient *Client) {
 	}
 
 	// start a ticker to pick a new server
-	ticker := exponentTicker(ctx)
+	ticker := g.exponentTicker(ctx)
 	defer ticker.Stop()
 
 	for {
@@ -125,11 +131,11 @@ func (g *Guard) notifyReconnected() {
 	}
 }
 
-func exponentTicker(ctx context.Context) *backoff.Ticker {
+func (g *Guard) exponentTicker(ctx context.Context) *backoff.Ticker {
 	bo := backoff.WithContext(&backoff.ExponentialBackOff{
 		InitialInterval: 2 * time.Second,
 		Multiplier:      2,
-		MaxInterval:     reconnectingTimeout,
+		MaxInterval:     g.maxBackoffInterval,
 		Clock:           backoff.SystemClock,
 	}, ctx)
 

shared/relay/client/manager.go

@@ -39,6 +39,15 @@ func NewRelayTrack() *RelayTrack {
 
 type OnServerCloseListener func()
 
+// ManagerOption configures a Manager at construction time.
+type ManagerOption func(*Manager)
+
+// WithMaxBackoffInterval caps the exponential backoff between reconnect
+// attempts to the home relay. A non-positive value keeps the default.
+func WithMaxBackoffInterval(d time.Duration) ManagerOption {
+	return func(m *Manager) { m.maxBackoffInterval = d }
+}
+
 // Manager is a manager for the relay client instances. It establishes one persistent connection to the given relay URL
 // and automatically reconnect to them in case disconnection.
 // The manager also manage temporary relay connection. If a client wants to communicate with a client on a
@@ -64,12 +73,13 @@ type Manager struct {
 	onReconnectedListenerFn func()
 	listenerLock            sync.Mutex
 
-	mtu uint16
+	mtu                uint16
+	maxBackoffInterval time.Duration
 }
 
 // NewManager creates a new manager instance.
 // The serverURL address can be empty. In this case, the manager will not serve.
-func NewManager(ctx context.Context, serverURLs []string, peerID string, mtu uint16) *Manager {
+func NewManager(ctx context.Context, serverURLs []string, peerID string, mtu uint16, opts ...ManagerOption) *Manager {
 	tokenStore := &relayAuth.TokenStore{}
 
 	m := &Manager{
@@ -86,8 +96,11 @@ func NewManager(ctx context.Context, serverURLs []string, peerID string, mtu uin
 		relayClients:            make(map[string]*RelayTrack),
 		onDisconnectedListeners: make(map[string]*list.List),
 	}
+	for _, opt := range opts {
+		opt(m)
+	}
 	m.serverPicker.ServerURLs.Store(serverURLs)
-	m.reconnectGuard = NewGuard(m.serverPicker)
+	m.reconnectGuard = NewGuard(m.serverPicker, m.maxBackoffInterval)
 	return m
 }
 
@@ -290,19 +303,36 @@ func (m *Manager) onServerConnected() {
 	go m.onReconnectedListenerFn()
 }
 
-// onServerDisconnected start to reconnection for home server only
+// onServerDisconnected handles relay disconnect events. For the home server it
+// starts the reconnect guard. For foreign servers it evicts the now-dead client
+// from the cache so the next OpenConn builds a fresh one instead of reusing a
+// closed client.
 func (m *Manager) onServerDisconnected(serverAddress string) {
 	m.relayClientMu.Lock()
-	if serverAddress == m.relayClient.connectionURL {
+	isHome := m.relayClient != nil && serverAddress == m.relayClient.connectionURL
+	if isHome {
 		go func(client *Client) {
 			m.reconnectGuard.StartReconnectTrys(m.ctx, client)
 		}(m.relayClient)
 	}
 	m.relayClientMu.Unlock()
 
+	if !isHome {
+		m.evictForeignRelay(serverAddress)
+	}
+
 	m.notifyOnDisconnectListeners(serverAddress)
 }
 
+func (m *Manager) evictForeignRelay(serverAddress string) {
+	m.relayClientsMutex.Lock()
+	defer m.relayClientsMutex.Unlock()
+	if _, ok := m.relayClients[serverAddress]; ok {
+		delete(m.relayClients, serverAddress)
+		log.Debugf("evicted disconnected foreign relay client: %s", serverAddress)
+	}
+}
+
 func (m *Manager) listenGuardEvent(ctx context.Context) {
 	for {
 		select {

shared/relay/client/manager_test.go

@@ -2,6 +2,7 @@ package client
 
 import (
 	"context"
+	"fmt"
 	"testing"
 	"time"
 
@@ -360,7 +361,8 @@ func TestAutoReconnect(t *testing.T) {
 		t.Fatalf("failed to serve manager: %s", err)
 	}
 
-	clientAlice := NewManager(mCtx, toURL(srvCfg), "alice", iface.DefaultMTU)
+	clientAlice := NewManager(mCtx, toURL(srvCfg), "alice", iface.DefaultMTU,
+		WithMaxBackoffInterval(2*time.Second))
 	err = clientAlice.Serve()
 	if err != nil {
 		t.Fatalf("failed to serve manager: %s", err)
@@ -384,7 +386,9 @@ func TestAutoReconnect(t *testing.T) {
 	}
 
 	log.Infof("waiting for reconnection")
-	time.Sleep(reconnectingTimeout + 1*time.Second)
+	if err := waitForReady(ctx, clientAlice, 15*time.Second); err != nil {
+		t.Fatalf("manager did not reconnect: %s", err)
+	}
 
 	log.Infof("reopent the connection")
 	_, err = clientAlice.OpenConn(ctx, ra, "bob")
@@ -393,6 +397,21 @@ func TestAutoReconnect(t *testing.T) {
 	}
 }
 
+func waitForReady(ctx context.Context, m *Manager, timeout time.Duration) error {
+	deadline := time.Now().Add(timeout)
+	for time.Now().Before(deadline) {
+		if m.Ready() {
+			return nil
+		}
+		select {
+		case <-time.After(100 * time.Millisecond):
+		case <-ctx.Done():
+			return ctx.Err()
+		}
+	}
+	return fmt.Errorf("manager not ready within %s", timeout)
+}
+
 func TestNotifierDoubleAdd(t *testing.T) {
 	ctx := context.Background()