cmd/cli: handle stop signal from service manager

So using "ctrld stop" or service manager to stop ctrld will end up with
the same result, stopped ctrld with a working DNS, and deactivation pin
code will always have effects if set.

cmd/cli/prog.go

@@ -87,6 +87,7 @@ type prog struct {
 	mu                   sync.Mutex
 	waitCh               chan struct{}
 	stopCh               chan struct{}
+	pinCodeValidCh       chan struct{}
 	reloadCh             chan struct{} // For Windows.
 	reloadDoneCh         chan struct{}
 	apiReloadCh          chan *ctrld.Config
@@ -268,13 +269,6 @@ func (p *prog) preRun() {
 		p.requiredMultiNICsConfig = requiredMultiNICsConfig()
 	}
 	p.runningIface = iface
-	if runtime.GOOS == "darwin" {
-		p.onStopped = append(p.onStopped, func() {
-			if !service.Interactive() {
-				p.resetDNS(false, true)
-			}
-		})
-	}
 }
 
 func (p *prog) postRun() {
@@ -622,14 +616,41 @@ func (p *prog) metricsEnabled() bool {
 func (p *prog) Stop(s service.Service) error {
 	p.stopDnsWatchers()
 	mainLog.Load().Debug().Msg("dns watchers stopped")
+	for _, f := range p.onStopped {
+		f()
+	}
+	mainLog.Load().Debug().Msg("finish running onStopped functions")
 	defer func() {
 		mainLog.Load().Info().Msg("Service stopped")
 	}()
-	close(p.stopCh)
 	if err := p.deAllocateIP(); err != nil {
 		mainLog.Load().Error().Err(err).Msg("de-allocate ip failed")
 		return err
 	}
+	if deactivationPinSet() {
+		select {
+		case <-p.pinCodeValidCh:
+			// Allow stopping the service, pinCodeValidCh is only filled
+			// after control server did validate the pin code.
+		case <-time.After(time.Millisecond * 100):
+			// No valid pin code was checked, that mean we are stopping
+			// because of OS signal sent directly from someone else.
+			// In this case, restarting ctrld service by ourselves.
+			mainLog.Load().Debug().Msgf("receiving stopping signal without valid pin code")
+			mainLog.Load().Debug().Msgf("self restarting ctrld service")
+			if exe, err := os.Executable(); err == nil {
+				cmd := exec.Command(exe, "restart")
+				cmd.SysProcAttr = sysProcAttrForDetachedChildProcess()
+				if err := cmd.Start(); err != nil {
+					mainLog.Load().Error().Err(err).Msg("failed to run self restart command")
+				}
+			} else {
+				mainLog.Load().Error().Err(err).Msg("failed to self restart ctrld service")
+			}
+			os.Exit(deactivationPinInvalidExitCode)
+		}
+	}
+	close(p.stopCh)
 	return nil
 }
 
@@ -1471,7 +1492,7 @@ func selfUpgradeCheck(vt string, cv *semver.Version, logger *zerolog.Logger) {
 		return
 	}
 	cmd := exec.Command(exe, "upgrade", "prod", "-vv")
-	cmd.SysProcAttr = sysProcAttrForSelfUpgrade()
+	cmd.SysProcAttr = sysProcAttrForDetachedChildProcess()
 	if err := cmd.Start(); err != nil {
 		mainLog.Load().Error().Err(err).Msg("failed to start self-upgrade")
 		return