wip: migrate to mono-repo. SPN has already been moved to spn/

service/resolver/main.go

@@ -0,0 +1,249 @@
+package resolver
+
+import (
+	"context"
+	"fmt"
+	"net"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/tevino/abool"
+
+	"github.com/safing/portbase/log"
+	"github.com/safing/portbase/modules"
+	"github.com/safing/portbase/notifications"
+	"github.com/safing/portbase/utils/debug"
+	_ "github.com/safing/portmaster/service/core/base"
+	"github.com/safing/portmaster/service/intel"
+	"github.com/safing/portmaster/service/netenv"
+)
+
+var module *modules.Module
+
+func init() {
+	module = modules.Register("resolver", prep, start, nil, "base", "netenv")
+}
+
+func prep() error {
+	// Set DNS test connectivity function for the online status check
+	netenv.DNSTestQueryFunc = func(ctx context.Context, fdqn string) (ips []net.IP, ok bool, err error) {
+		return testConnectivity(ctx, fdqn, nil)
+	}
+
+	intel.SetReverseResolver(ResolveIPAndValidate)
+
+	if err := registerAPI(); err != nil {
+		return err
+	}
+
+	if err := prepEnvResolver(); err != nil {
+		return err
+	}
+
+	return prepConfig()
+}
+
+func start() error {
+	// load resolvers from config and environment
+	loadResolvers()
+
+	// reload after network change
+	err := module.RegisterEventHook(
+		"netenv",
+		"network changed",
+		"update nameservers",
+		func(_ context.Context, _ interface{}) error {
+			loadResolvers()
+			log.Debug("resolver: reloaded nameservers due to network change")
+			return nil
+		},
+	)
+	if err != nil {
+		return err
+	}
+
+	// Force resolvers to reconnect when SPN has connected.
+	if err := module.RegisterEventHook(
+		"captain",
+		"spn connect", // Defined by captain.SPNConnectedEvent
+		"force resolver reconnect",
+		func(ctx context.Context, _ any) error {
+			ForceResolverReconnect(ctx)
+			return nil
+		},
+	); err != nil {
+		// This module does not depend on the SPN/Captain module, and probably should not.
+		log.Warningf("resolvers: failed to register event hook for captain/spn-connect: %s", err)
+	}
+
+	// reload after config change
+	prevNameservers := strings.Join(configuredNameServers(), " ")
+	err = module.RegisterEventHook(
+		"config",
+		"config change",
+		"update nameservers",
+		func(_ context.Context, _ interface{}) error {
+			newNameservers := strings.Join(configuredNameServers(), " ")
+			if newNameservers != prevNameservers {
+				prevNameservers = newNameservers
+
+				loadResolvers()
+				log.Debug("resolver: reloaded nameservers due to config change")
+			}
+			return nil
+		},
+	)
+	if err != nil {
+		return err
+	}
+
+	// Check failing resolvers regularly and when the network changes.
+	checkFailingResolversTask := module.NewTask("check failing resolvers", checkFailingResolvers).Repeat(1 * time.Minute)
+	err = module.RegisterEventHook(
+		"netenv",
+		netenv.NetworkChangedEvent,
+		"check failing resolvers",
+		func(_ context.Context, _ any) error {
+			checkFailingResolversTask.StartASAP()
+			return nil
+		},
+	)
+	if err != nil {
+		return err
+	}
+
+	module.NewTask("suggest using stale cache", suggestUsingStaleCacheTask).Repeat(2 * time.Minute)
+
+	module.StartServiceWorker(
+		"mdns handler",
+		5*time.Second,
+		listenToMDNS,
+	)
+
+	module.StartServiceWorker("name record delayed cache writer", 0, recordDatabase.DelayedCacheWriter)
+	module.StartServiceWorker("ip info delayed cache writer", 0, ipInfoDatabase.DelayedCacheWriter)
+
+	return nil
+}
+
+var localAddrFactory func(network string) net.Addr
+
+// SetLocalAddrFactory supplies the intel package with a function to get permitted local addresses for connections.
+func SetLocalAddrFactory(laf func(network string) net.Addr) {
+	if localAddrFactory == nil {
+		localAddrFactory = laf
+	}
+}
+
+func getLocalAddr(network string) net.Addr {
+	if localAddrFactory != nil {
+		return localAddrFactory(network)
+	}
+	return nil
+}
+
+var (
+	failingResolverNotification     *notifications.Notification
+	failingResolverNotificationSet  = abool.New()
+	failingResolverNotificationLock sync.Mutex
+
+	failingResolverErrorID = "resolver:all-configured-resolvers-failed"
+)
+
+func notifyAboutFailingResolvers() {
+	failingResolverNotificationLock.Lock()
+	defer failingResolverNotificationLock.Unlock()
+	failingResolverNotificationSet.Set()
+
+	// Check if already set.
+	if failingResolverNotification != nil {
+		return
+	}
+
+	// Create new notification.
+	n := &notifications.Notification{
+		EventID: failingResolverErrorID,
+		Type:    notifications.Error,
+		Title:   "Configured DNS Servers Failing",
+		Message: `All configured DNS servers in Portmaster are failing.
+
+You might not be able to connect to these servers, or all of these servers are offline.  
+Choosing different DNS servers might fix this problem.
+
+While the issue persists, Portmaster will use the DNS servers from your system or network, if permitted by configuration.
+
+Alternatively, there might be something on your device that is interfering with Portmaster. This could be a firewall or another secure DNS resolver software. If that is your suspicion, please [check if you are running incompatible software here](https://docs.safing.io/portmaster/install/status/software-compatibility).
+
+This notification will go away when Portmaster detects a working configured DNS server.`,
+		ShowOnSystem: true,
+		AvailableActions: []*notifications.Action{{
+			Text: "Change DNS Servers",
+			Type: notifications.ActionTypeOpenSetting,
+			Payload: &notifications.ActionTypeOpenSettingPayload{
+				Key: CfgOptionNameServersKey,
+			},
+		}},
+	}
+	notifications.Notify(n)
+
+	failingResolverNotification = n
+	n.AttachToModule(module)
+}
+
+func resetFailingResolversNotification() {
+	if failingResolverNotificationSet.IsNotSet() {
+		return
+	}
+
+	failingResolverNotificationLock.Lock()
+	defer failingResolverNotificationLock.Unlock()
+
+	// Remove the notification.
+	if failingResolverNotification != nil {
+		failingResolverNotification.Delete()
+		failingResolverNotification = nil
+	}
+
+	// Additionally, resolve the module error, if not done through the notification.
+	module.Resolve(failingResolverErrorID)
+}
+
+// AddToDebugInfo adds the system status to the given debug.Info.
+func AddToDebugInfo(di *debug.Info) {
+	resolversLock.Lock()
+	defer resolversLock.Unlock()
+
+	content := make([]string, 0, (len(globalResolvers)*4)-1)
+	var working, total int
+	for i, resolver := range globalResolvers {
+		// Count for summary.
+		total++
+		failing := resolver.Conn.IsFailing()
+		if !failing {
+			working++
+		}
+
+		// Add section.
+		content = append(content, resolver.Info.DescriptiveName())
+		content = append(content, fmt.Sprintf("  %s", resolver.Info.ID()))
+		if resolver.SearchOnly {
+			content = append(content, "  Used for search domains only!")
+		}
+		if len(resolver.Search) > 0 {
+			content = append(content, fmt.Sprintf("  Search Domains: %v", strings.Join(resolver.Search, ", ")))
+		}
+		content = append(content, fmt.Sprintf("  Failing: %v", resolver.Conn.IsFailing()))
+
+		// Add a empty line for all but the last entry.
+		if i+1 < len(globalResolvers) {
+			content = append(content, "")
+		}
+	}
+
+	di.AddSection(
+		fmt.Sprintf("Resolvers: %d/%d", working, total),
+		debug.UseCodeSection|debug.AddContentLineBreaks,
+		content...,
+	)
+}