update checks for wrapped errors (#3117)

* errors.Is()
* extract function isBrokenConnection()

.golangci.yml

@@ -348,10 +348,6 @@ issues:
         - errorlint
       text: "type switch on error will fail on wrapped errors. Use errors.As to check for specific errors"
 
-    - linters:
-        - errorlint
-      text: "comparing with .* will fail on wrapped errors. Use errors.Is to check for a specific error"
-
     - linters:
         - nosprintfhostport
       text: "host:port in url should be constructed with net.JoinHostPort and not directly with fmt.Sprintf"

pkg/acquisition/modules/appsec/appsec.go

@@ -85,6 +85,7 @@ func (ac *AuthCache) Get(apiKey string) (time.Time, bool) {
 	ac.mu.RLock()
 	expiration, exists := ac.APIKeys[apiKey]
 	ac.mu.RUnlock()
+
 	return expiration, exists
 }
 
@@ -128,6 +129,7 @@ func (w *AppsecSource) UnmarshalConfig(yamlConfig []byte) error {
 		if w.config.ListenSocket != "" && w.config.ListenAddr == "" {
 			w.config.Name = w.config.ListenSocket
 		}
+
 		if w.config.ListenSocket == "" {
 			w.config.Name = fmt.Sprintf("%s%s", w.config.ListenAddr, w.config.Path)
 		}
@@ -153,6 +155,7 @@ func (w *AppsecSource) Configure(yamlConfig []byte, logger *log.Entry, MetricsLe
 	if err != nil {
 		return fmt.Errorf("unable to parse appsec configuration: %w", err)
 	}
+
 	w.logger = logger
 	w.metricsLevel = MetricsLevel
 	w.logger.Tracef("Appsec configuration: %+v", w.config)
@@ -211,17 +214,20 @@ func (w *AppsecSource) Configure(yamlConfig []byte, logger *log.Entry, MetricsLe
 			AppsecRuntime: &wrt,
 			Labels:        w.config.Labels,
 		}
+
 		err := runner.Init(appsecCfg.GetDataDir())
 		if err != nil {
 			return fmt.Errorf("unable to initialize runner: %w", err)
 		}
+
 		w.AppsecRunners[nbRoutine] = runner
 	}
 
 	w.logger.Infof("Created %d appsec runners", len(w.AppsecRunners))
 
 	// We don´t use the wrapper provided by coraza because we want to fully control what happens when a rule match to send the information in crowdsec
 	w.mux.HandleFunc(w.config.Path, w.appsecHandler)
+
 	return nil
 }
 
@@ -243,17 +249,20 @@ func (w *AppsecSource) OneShotAcquisition(_ context.Context, _ chan types.Event,
 
 func (w *AppsecSource) StreamingAcquisition(ctx context.Context, out chan types.Event, t *tomb.Tomb) error {
 	w.outChan = out
+
 	t.Go(func() error {
 		defer trace.CatchPanic("crowdsec/acquis/appsec/live")
 
 		w.logger.Infof("%d appsec runner to start", len(w.AppsecRunners))
+
 		for _, runner := range w.AppsecRunners {
 			runner.outChan = out
 			t.Go(func() error {
 				defer trace.CatchPanic("crowdsec/acquis/appsec/live/runner")
 				return runner.Run(t)
 			})
 		}
+
 		t.Go(func() error {
 			if w.config.ListenSocket != "" {
 				w.logger.Infof("creating unix socket %s", w.config.ListenSocket)
@@ -268,10 +277,11 @@ func (w *AppsecSource) StreamingAcquisition(ctx context.Context, out chan types.
 				} else {
 					err = w.server.Serve(listener)
 				}
-				if err != nil && err != http.ErrServerClosed {
+				if err != nil && !errors.Is(err, http.ErrServerClosed) {
 					return fmt.Errorf("appsec server failed: %w", err)
 				}
 			}
+
 			return nil
 		})
 		t.Go(func() error {
@@ -288,6 +298,7 @@ func (w *AppsecSource) StreamingAcquisition(ctx context.Context, out chan types.
 					return fmt.Errorf("appsec server failed: %w", err)
 				}
 			}
+
 			return nil
 		})
 		<-t.Dying()
@@ -297,6 +308,7 @@ func (w *AppsecSource) StreamingAcquisition(ctx context.Context, out chan types.
 		w.server.Shutdown(ctx)
 		return nil
 	})
+
 	return nil
 }
 
@@ -391,6 +403,7 @@ func (w *AppsecSource) appsecHandler(rw http.ResponseWriter, r *http.Request) {
 	logger.Debugf("Response: %+v", appsecResponse)
 
 	rw.WriteHeader(statusCode)
+
 	body, err := json.Marshal(appsecResponse)
 	if err != nil {
 		logger.Errorf("unable to serialize response: %s", err)

pkg/acquisition/modules/wineventlog/wineventlog_windows.go

@@ -94,7 +94,7 @@ func (w *WinEventLogSource) getXMLEvents(config *winlog.SubscribeConfig, publish
 		2000,                // Timeout in milliseconds to wait.
 		0,                   // Reserved. Must be zero.
 		&returned)           // The number of handles in the array that are set by the API.
-	if err == windows.ERROR_NO_MORE_ITEMS {
+	if errors.Is(err, windows.ERROR_NO_MORE_ITEMS) {
 		return nil, err
 	} else if err != nil {
 		return nil, fmt.Errorf("wevtapi.EvtNext failed: %v", err)
@@ -188,7 +188,7 @@ func (w *WinEventLogSource) getEvents(out chan types.Event, t *tomb.Tomb) error
 			}
 			if status == syscall.WAIT_OBJECT_0 {
 				renderedEvents, err := w.getXMLEvents(w.evtConfig, publisherCache, subscription, 500)
-				if err == windows.ERROR_NO_MORE_ITEMS {
+				if errors.Is(err, windows.ERROR_NO_MORE_ITEMS) {
 					windows.ResetEvent(w.evtConfig.SignalEvent)
 				} else if err != nil {
 					w.logger.Errorf("getXMLEvents failed: %v", err)
@@ -411,7 +411,7 @@ OUTER_LOOP:
 			return nil
 		default:
 			evts, err := w.getXMLEvents(w.evtConfig, publisherCache, handle, 500)
-			if err == windows.ERROR_NO_MORE_ITEMS {
+			if errors.Is(err, windows.ERROR_NO_MORE_ITEMS) {
 				log.Info("No more items")
 				break OUTER_LOOP
 			} else if err != nil {

pkg/apiserver/apiserver.go

@@ -46,20 +46,11 @@ type APIServer struct {
 	consoleConfig  *csconfig.ConsoleConfig
 }
 
-func recoverFromPanic(c *gin.Context) {
-	err := recover()
-	if err == nil {
-		return
-	}
-
-	// Check for a broken connection, as it is not really a
-	// condition that warrants a panic stack trace.
-	brokenPipe := false
-
+func isBrokenConnection(err any) bool {
 	if ne, ok := err.(*net.OpError); ok {
 		if se, ok := ne.Err.(*os.SyscallError); ok {
 			if strings.Contains(strings.ToLower(se.Error()), "broken pipe") || strings.Contains(strings.ToLower(se.Error()), "connection reset by peer") {
-				brokenPipe = true
+				return true
 			}
 		}
 	}
@@ -79,11 +70,22 @@ func recoverFromPanic(c *gin.Context) {
 			errors.Is(strErr, errClosedBody) ||
 			errors.Is(strErr, errHandlerComplete) ||
 			errors.Is(strErr, errStreamClosed) {
-			brokenPipe = true
+			return true
 		}
 	}
 
-	if brokenPipe {
+	return false
+}
+
+func recoverFromPanic(c *gin.Context) {
+	err := recover()
+	if err == nil {
+		return
+	}
+
+	// Check for a broken connection, as it is not really a
+	// condition that warrants a panic stack trace.
+	if isBrokenConnection(err) {
 		log.Warningf("client %s disconnected: %s", c.ClientIP(), err)
 		c.Abort()
 	} else {