[service] Fix module failure when dll is missing

service/firewall/interception/dnsmonitor/etwlink_windows.go

@@ -14,7 +14,7 @@ import (
 )
 
 type ETWSession struct {
-	i integration.ETWFunctions
+	i *integration.ETWFunctions
 
 	shutdownGuard atomic.Bool
 	shutdownMutex sync.Mutex
@@ -23,7 +23,10 @@ type ETWSession struct {
 }
 
 // NewSession creates new ETW event listener and initilizes it. This is a low level interface, make sure to call DestorySession when you are done using it.
-func NewSession(etwInterface integration.ETWFunctions, callback func(domain string, result string)) (*ETWSession, error) {
+func NewSession(etwInterface *integration.ETWFunctions, callback func(domain string, result string)) (*ETWSession, error) {
+	if etwInterface == nil {
+		return nil, fmt.Errorf("etw interface was nil")
+	}
 	etwSession := &ETWSession{
 		i: etwInterface,
 	}
@@ -47,7 +50,7 @@ func NewSession(etwInterface integration.ETWFunctions, callback func(domain stri
 	// Initialize session.
 	err := etwSession.i.InitializeSession(etwSession.state)
 	if err != nil {
-		return nil, fmt.Errorf("failed to initialzie session: %q", err)
+		return nil, fmt.Errorf("failed to initialize session: %q", err)
 	}
 
 	return etwSession, nil

service/firewall/interception/dnsmonitor/eventlistener_windows.go

@@ -23,19 +23,32 @@ func newListener(module *DNSMonitor) (*Listener, error) {
 	ResolverInfo.Source = resolver.ServerSourceETW
 
 	listener := &Listener{}
-	var err error
 	// Initialize new dns event session.
-	listener.etw, err = NewSession(module.instance.OSIntegration().GetETWInterface(), listener.processEvent)
+	err := initializeSessions(module, listener)
 	if err != nil {
-		return nil, err
+		// Listen for event if the dll has been loaded
+		module.instance.OSIntegration().OnInitializedEvent.AddCallback("loader-listener", func(wc *mgr.WorkerCtx, s struct{}) (cancel bool, err error) {
+			err = initializeSessions(module, listener)
+			if err != nil {
+				return false, err
+			}
+			return true, nil
+		})
 	}
+	return listener, nil
+}
 
-	// Start listening for events.
+func initializeSessions(module *DNSMonitor, listener *Listener) error {
+	var err error
+	listener.etw, err = NewSession(module.instance.OSIntegration().GetETWInterface(), listener.processEvent)
+	if err != nil {
+		return err
+	}
+	// Start listener
 	module.mgr.Go("etw-dns-event-listener", func(w *mgr.WorkerCtx) error {
 		return listener.etw.StartTrace()
 	})
-
-	return listener, nil
+	return nil
 }
 
 func (l *Listener) flush() error {

service/integration/etw_windows.go

@@ -19,8 +19,8 @@ type ETWFunctions struct {
 	stopOldSession    *windows.Proc
 }
 
-func initializeETW(dll *windows.DLL) (ETWFunctions, error) {
-	var functions ETWFunctions
+func initializeETW(dll *windows.DLL) (*ETWFunctions, error) {
+	functions := &ETWFunctions{}
 	var err error
 	functions.createState, err = dll.FindProc("PM_ETWCreateState")
 	if err != nil {

service/integration/integration_windows.go

@@ -6,23 +6,42 @@ package integration
 import (
 	"fmt"
 
+	"github.com/safing/portmaster/base/log"
+	"github.com/safing/portmaster/service/mgr"
 	"github.com/safing/portmaster/service/updates"
 	"golang.org/x/sys/windows"
 )
 
 type OSSpecific struct {
 	dll          *windows.DLL
-	etwFunctions ETWFunctions
+	etwFunctions *ETWFunctions
 }
 
 // Initialize loads the dll and finds all the needed functions from it.
 func (i *OSIntegration) Initialize() error {
+	// Try to load dll
+	err := i.loadDLL()
+	if err != nil {
+		log.Errorf("integration: failed to load dll: %s", err)
+
+		// listen for event from the updater and try to load again if any.
+		i.instance.Updates().EventResourcesUpdated.AddCallback("core-dll-loader", func(wc *mgr.WorkerCtx, s struct{}) (cancel bool, err error) {
+			err = i.loadDLL()
+			if err != nil {
+				log.Errorf("integration: failed to load dll: %s", err)
+			}
+			return false, nil
+		})
+	}
+	return nil
+}
+
+func (i *OSIntegration) loadDLL() error {
 	// Find path to the dll.
 	file, err := updates.GetPlatformFile("dll/portmaster-core.dll")
 	if err != nil {
 		return err
 	}
-
 	// Load the DLL.
 	i.os.dll, err = windows.LoadDLL(file.Path())
 	if err != nil {
@@ -35,18 +54,21 @@ func (i *OSIntegration) Initialize() error {
 		return err
 	}
 
+	// Notify listeners
+	i.OnInitializedEvent.Submit(struct{}{})
+
 	return nil
 }
 
-// CleanUp releases any resourses allocated during initializaion.
+// CleanUp releases any resources allocated during initialization.
 func (i *OSIntegration) CleanUp() error {
 	if i.os.dll != nil {
 		return i.os.dll.Release()
 	}
 	return nil
 }
 
-// GetETWInterface return struct containing all the ETW related functions.
-func (i *OSIntegration) GetETWInterface() ETWFunctions {
+// GetETWInterface return struct containing all the ETW related functions, and nil if it was not loaded yet
+func (i *OSIntegration) GetETWInterface() *ETWFunctions {
 	return i.os.etwFunctions
 }

service/integration/module.go

@@ -7,8 +7,9 @@ import (
 
 // OSIntegration module provides special integration with the OS.
 type OSIntegration struct {
-	m      *mgr.Manager
-	states *mgr.StateMgr
+	m *mgr.Manager
+
+	OnInitializedEvent *mgr.EventMgr[struct{}]
 
 	//nolint:unused
 	os OSSpecific
@@ -20,10 +21,9 @@ type OSIntegration struct {
 func New(instance instance) (*OSIntegration, error) {
 	m := mgr.New("OSIntegration")
 	module := &OSIntegration{
-		m:      m,
-		states: m.NewStateMgr(),
-
-		instance: instance,
+		m:                  m,
+		OnInitializedEvent: mgr.NewEventMgr[struct{}]("on-initialized", m),
+		instance:           instance,
 	}
 
 	return module, nil