Update golangci-lint

.github/workflows/build.yml

@@ -34,10 +34,9 @@ jobs:
     - name: Checkout repo
       uses: actions/checkout@v3
     - name: Lint the codebase
-      uses: golangci/golangci-lint-action@v3
+      uses: golangci/golangci-lint-action@v8
       with:
         version: latest
-        args: -E goimports -E godot
     - name: Run tests
       run: |
         go test -v ./... -cover -race -coverprofile=coverage.out

.golangci.yml

@@ -0,0 +1,9 @@
+version: "2"
+
+linters:
+  enable:
+    - godot
+
+formatters:
+  enable:
+    - goimports

httpmuxer/httpmuxer.go

@@ -459,7 +459,12 @@ func Start(state *utils.State) {
 				state.TCPListeners.Store(httpsServer.Addr, tH)
 			}
 
-			defer httpsListener.Close()
+			defer func() {
+				err := httpsListener.Close()
+				if err != nil {
+					log.Println("Error closing https listener:", err)
+				}
+			}()
 
 			log.Fatal(httpsServer.ServeTLS(httpsListener, "", ""))
 		}()
@@ -491,7 +496,12 @@ func Start(state *utils.State) {
 		httpListener = l
 	}
 
-	defer httpListener.Close()
+	defer func() {
+		err := httpListener.Close()
+		if err != nil {
+			log.Println("Error closing http listener:", err)
+		}
+	}()
 
 	log.Fatal(httpServer.Serve(httpListener))
 }

httpmuxer/https.go

@@ -26,7 +26,15 @@ func (pL *proxyListener) Accept() (net.Conn, error) {
 	clientRemote, _, err := net.SplitHostPort(cl.RemoteAddr().String())
 
 	if err != nil || pL.State.IPFilter.Blocked(clientRemote) {
-		cl.Close()
+		err := cl.Close()
+		if err != nil {
+			log.Println("Error closing connection:", err)
+		}
+
+		if viper.GetBool("debug") {
+			log.Printf("Blocked connection from %s to %s", cl.RemoteAddr().String(), cl.LocalAddr().String())
+		}
+
 		return pL.Accept()
 	}
 
@@ -58,14 +66,24 @@ func (pL *proxyListener) Accept() (net.Conn, error) {
 	connectionLocation, err := balancer.NextServer()
 	if err != nil {
 		log.Println("Unable to load connection location:", err)
-		teeConn.Close()
+
+		err := teeConn.Close()
+		if err != nil {
+			log.Println("Error closing teeConn:", err)
+		}
+
 		return pL.Accept()
 	}
 
 	host, err := base64.StdEncoding.DecodeString(connectionLocation.Host)
 	if err != nil {
 		log.Println("Unable to decode connection location:", err)
-		teeConn.Close()
+
+		err := teeConn.Close()
+		if err != nil {
+			log.Println("Error closing teeConn:", err)
+		}
+
 		return pL.Accept()
 	}
 
@@ -93,7 +111,12 @@ func (pL *proxyListener) Accept() (net.Conn, error) {
 	conn, err := net.Dial("unix", hostAddr)
 	if err != nil {
 		log.Println("Error connecting to tcp balancer:", err)
-		teeConn.Close()
+
+		err := teeConn.Close()
+		if err != nil {
+			log.Println("Error closing teeConn:", err)
+		}
+
 		return pL.Accept()
 	}
 

sshmuxer/channels.go

@@ -421,14 +421,14 @@ func getProxyProtoVersion(proxyProtoUserVersion string) byte {
 		proxyProtoUserVersion = viper.GetString("proxy-protocol-version")
 	}
 
-	realProtoVersion := 0
-	if proxyProtoUserVersion == "1" {
-		realProtoVersion = 1
-	} else if proxyProtoUserVersion == "2" {
-		realProtoVersion = 2
+	switch proxyProtoUserVersion {
+	case "1":
+		return 1
+	case "2":
+		return 2
+	default:
+		return 0
 	}
-
-	return byte(realProtoVersion)
 }
 
 // parseDeadline parses the deadline string provided by the client to a time object.

sshmuxer/requests.go

@@ -66,7 +66,12 @@ func handleCancelRemoteForward(newRequest *ssh.Request, sshConn *utils.SSHConnec
 
 		if holder.OriginalAddr == check.Addr && holder.OriginalPort == check.Rport {
 			closed = true
-			holder.Close()
+
+			err := holder.Close()
+			if err != nil {
+				log.Println("Error closing listener:", err)
+			}
+
 			return false
 		}
 
@@ -174,8 +179,16 @@ func handleRemoteForward(newRequest *ssh.Request, sshConn *utils.SSHConnection,
 		}
 		return
 	}
-	tmpfile.Close()
-	os.Remove(tmpfile.Name())
+
+	err = tmpfile.Close()
+	if err != nil {
+		log.Println("Error closing temporary file:", err)
+	}
+
+	err = os.Remove(tmpfile.Name())
+	if err != nil {
+		log.Println("Error removing temporary file:", err)
+	}
 
 	listenAddr := tmpfile.Name()
 
@@ -205,10 +218,19 @@ func handleRemoteForward(newRequest *ssh.Request, sshConn *utils.SSHConnection,
 	deferHandler := func() {}
 
 	cleanupChanListener := func() {
-		listenerHolder.Close()
+		err := listenerHolder.Close()
+		if err != nil {
+			log.Println("Error closing listener:", err)
+		}
+
 		state.Listeners.Delete(listenAddr)
 		sshConn.Listeners.Delete(listenAddr)
-		os.Remove(listenAddr)
+
+		err = os.Remove(listenAddr)
+		if err != nil {
+			log.Println("Error removing unix socket:", err)
+		}
+
 		deferHandler()
 	}
 
@@ -334,7 +356,11 @@ func handleRemoteForward(newRequest *ssh.Request, sshConn *utils.SSHConnection,
 				})
 
 				if balancers == 0 {
-					tH.Listener.Close()
+					err := tH.Listener.Close()
+					if err != nil {
+						log.Println("Error closing TCPListener:", err)
+					}
+
 					state.Listeners.Delete(tcpAddr)
 					state.TCPListeners.Delete(tcpAddr)
 				}
@@ -373,7 +399,11 @@ func handleRemoteForward(newRequest *ssh.Request, sshConn *utils.SSHConnection,
 				newChan, newReqs, err := sshConn.SSHConn.OpenChannel("forwarded-tcpip", ssh.Marshal(resp))
 				if err != nil {
 					sshConn.SendMessage(err.Error(), true)
-					cl.Close()
+
+					err := cl.Close()
+					if err != nil {
+						log.Println("Error closing client connection:", err)
+					}
 				}
 
 				if sshConn.ProxyProto != 0 && listenerType == utils.TCPListener {

sshmuxer/sshmuxer.go

@@ -182,7 +182,11 @@ func Start() {
 	state.Listeners.Store(viper.GetString("ssh-address"), listener)
 
 	defer func() {
-		listener.Close()
+		err := listener.Close()
+		if err != nil {
+			log.Println("Error closing listener:", err)
+		}
+
 		state.Listeners.Delete(viper.GetString("ssh-address"))
 	}()
 
@@ -205,7 +209,15 @@ func Start() {
 			clientRemote, _, err := net.SplitHostPort(conn.RemoteAddr().String())
 
 			if err != nil || state.IPFilter.Blocked(clientRemote) {
-				conn.Close()
+				err := conn.Close()
+				if err != nil {
+					log.Println("Error closing connection:", err)
+				}
+
+				if viper.GetBool("debug") {
+					log.Printf("Blocked connection from %s to %s", conn.RemoteAddr().String(), conn.LocalAddr().String())
+				}
+
 				return
 			}
 
@@ -220,7 +232,10 @@ func Start() {
 					<-time.After(viper.GetDuration("cleanup-unauthed-timeout"))
 					clientLoggedInMutex.Lock()
 					if !clientLoggedIn {
-						conn.Close()
+						err := conn.Close()
+						if err != nil {
+							log.Println("Error closing connection:", err)
+						}
 					}
 					clientLoggedInMutex.Unlock()
 				}()
@@ -233,8 +248,12 @@ func Start() {
 			clientLoggedIn = true
 			clientLoggedInMutex.Unlock()
 			if err != nil {
-				conn.Close()
-				log.Println(err)
+				err := conn.Close()
+				if err != nil {
+					log.Println("Error closing connection:", err)
+				}
+
+				log.Println("SSH connection could not be established", err)
 				return
 			}
 

utils/authentication_key_request_test.go

@@ -92,7 +92,13 @@ func HandleSSHConn(sshListener net.Listener, successAuth *chan bool) {
 	if err != nil {
 		log.Fatal(err)
 	}
-	defer conn.Close()
+
+	defer func() {
+		err := conn.Close()
+		if err != nil {
+			log.Print("Error closing connection", err)
+		}
+	}()
 
 	// GetSSHConfig is the method we are testing to validate that it
 	// can use an http request to validate client public key auth
@@ -102,7 +108,11 @@ func HandleSSHConn(sshListener net.Listener, successAuth *chan bool) {
 		*successAuth <- false
 		return
 	}
-	connection.Close()
+
+	err = connection.Close()
+	if err != nil {
+		log.Print("Error closing connection", err)
+	}
 
 	*successAuth <- true
 }
@@ -117,7 +127,14 @@ func TestAuthenticationKeyRequest(t *testing.T) {
 	if err != nil {
 		log.Fatal(err)
 	}
-	defer os.RemoveAll(dir)
+
+	defer func() {
+		err := os.RemoveAll(dir)
+		if err != nil {
+			t.Error(err)
+		}
+	}()
+
 	viper.Set("private-keys-directory", dir)
 	viper.Set("authentication", true)
 
@@ -193,7 +210,12 @@ func TestAuthenticationKeyRequest(t *testing.T) {
 		if err != nil {
 			t.Error(err)
 		}
-		defer sshListener.Close()
+		defer func() {
+			err := sshListener.Close()
+			if err != nil {
+				t.Error(err)
+			}
+		}()
 
 		successAuth := make(chan bool)
 		go HandleSSHConn(sshListener, &successAuth)
@@ -217,7 +239,10 @@ func TestAuthenticationKeyRequest(t *testing.T) {
 			t.Log("ssh client rejected", err)
 		} else {
 			t.Log("ssh client connected")
-			client.Close()
+			err := client.Close()
+			if err != nil {
+				t.Error(err)
+			}
 		}
 
 		didAuth := <-successAuth

utils/conn.go

@@ -82,7 +82,12 @@ func (s *SSHConnection) ListenerCount() int {
 func (s *SSHConnection) CleanUp(state *State) {
 	s.Closed.Do(func() {
 		close(s.Close)
-		s.SSHConn.Close()
+
+		err := s.SSHConn.Close()
+		if err != nil {
+			log.Println("Error closing SSH connection:", err)
+		}
+
 		state.SSHConnections.Delete(s.SSHConn.RemoteAddr().String())
 		log.Println("Closed SSH connection for:", s.SSHConn.RemoteAddr().String(), "user:", s.SSHConn.User())
 	})
@@ -208,8 +213,15 @@ func (i IdleTimeoutConn) Write(buf []byte) (int, error) {
 // CopyBoth copies betwen a reader and writer and will cleanup each.
 func CopyBoth(writer net.Conn, reader io.ReadWriteCloser) {
 	closeBoth := func() {
-		reader.Close()
-		writer.Close()
+		err := reader.Close()
+		if err != nil {
+			log.Println("Error closing reader:", err)
+		}
+
+		err = writer.Close()
+		if err != nil {
+			log.Println("Error closing writer:", err)
+		}
 	}
 
 	var tcon io.ReadWriter

utils/console.go

@@ -169,7 +169,10 @@ func (c *WebConsole) HandleDisconnectRoute(proxyUrl string, g *gin.Context) {
 		listener, ok := listenerTmp.(*ListenerHolder)
 
 		if ok {
-			listener.Close()
+			err := listener.Close()
+			if err != nil {
+				log.Println("Error closing listener:", err)
+			}
 		}
 	}
 
@@ -194,12 +197,7 @@ func (c *WebConsole) HandleClients(proxyUrl string, g *gin.Context) {
 		routeListeners := map[string]map[string]any{}
 
 		sshConn.Listeners.Range(func(name string, val net.Listener) bool {
-			ok := true
-			if name == "" {
-				ok = false
-			}
-
-			if ok {
+			if name != "" {
 				listeners = append(listeners, name)
 			}
 
@@ -347,7 +345,10 @@ func (c *WebConsole) RemoveRoute(route string) {
 	}
 
 	for _, client := range clients {
-		client.Conn.Close()
+		err := client.Conn.Close()
+		if err != nil {
+			log.Println("Error closing websocket connection:", err)
+		}
 	}
 
 	c.Clients.Delete(route)
@@ -407,7 +408,11 @@ func (c *WebConsole) BroadcastRoute(route string, message []byte) {
 // Handle is the only place socket reads and writes happen.
 func (c *WebClient) Handle() {
 	defer func() {
-		c.Conn.Close()
+		err := c.Conn.Close()
+		if err != nil {
+			log.Println("Error closing websocket connection:", err)
+		}
+
 		c.Console.RemoveClient(c.Route, c)
 	}()
 

utils/state.go

@@ -92,7 +92,15 @@ func (tH *TCPHolder) Handle(state *State) {
 			clientRemote, _, err := net.SplitHostPort(cl.RemoteAddr().String())
 
 			if err != nil || state.IPFilter.Blocked(clientRemote) {
-				cl.Close()
+				err := cl.Close()
+				if err != nil {
+					log.Printf("Unable to close connection: %s", err)
+				}
+
+				if viper.GetBool("debug") {
+					log.Printf("Blocked connection from %s to %s", cl.RemoteAddr().String(), cl.LocalAddr().String())
+				}
+
 				return
 			}
 
@@ -103,7 +111,12 @@ func (tH *TCPHolder) Handle(state *State) {
 				tlsHello, teeConn, err := PeekTLSHello(cl)
 				if tlsHello == nil {
 					log.Printf("Unable to read TLS hello: %s", err)
-					cl.Close()
+
+					err := cl.Close()
+					if err != nil {
+						log.Printf("Unable to close connection: %s", err)
+					}
+
 					return
 				}
 
@@ -112,7 +125,12 @@ func (tH *TCPHolder) Handle(state *State) {
 				_, err = io.ReadFull(teeConn, bufBytes)
 				if err != nil {
 					log.Printf("Unable to read buffered data: %s", err)
-					cl.Close()
+
+					err := cl.Close()
+					if err != nil {
+						log.Printf("Unable to close connection: %s", err)
+					}
+
 					return
 				}
 
@@ -131,7 +149,12 @@ func (tH *TCPHolder) Handle(state *State) {
 
 				if pB == nil {
 					log.Printf("Unable to load connection location: %s not found on TCP listener %s", balancerName, tH.TCPHost)
-					cl.Close()
+
+					err := cl.Close()
+					if err != nil {
+						log.Printf("Unable to close connection: %s", err)
+					}
+
 					return
 				}
 			}
@@ -141,14 +164,24 @@ func (tH *TCPHolder) Handle(state *State) {
 			connectionLocation, err := balancer.NextServer()
 			if err != nil {
 				log.Println("Unable to load connection location:", err)
-				cl.Close()
+
+				err := cl.Close()
+				if err != nil {
+					log.Printf("Unable to close connection: %s", err)
+				}
+
 				return
 			}
 
 			host, err := base64.StdEncoding.DecodeString(connectionLocation.Host)
 			if err != nil {
 				log.Println("Unable to decode connection location:", err)
-				cl.Close()
+
+				err := cl.Close()
+				if err != nil {
+					log.Printf("Unable to close connection: %s", err)
+				}
+
 				return
 			}
 
@@ -176,7 +209,12 @@ func (tH *TCPHolder) Handle(state *State) {
 			conn, err := net.Dial("unix", hostAddr)
 			if err != nil {
 				log.Println("Error connecting to tcp balancer:", err)
-				cl.Close()
+
+				err := cl.Close()
+				if err != nil {
+					log.Printf("Unable to close connection: %s", err)
+				}
+
 				return
 			}
 
@@ -184,7 +222,12 @@ func (tH *TCPHolder) Handle(state *State) {
 				_, err := conn.Write(bufBytes)
 				if err != nil {
 					log.Println("Unable to write to conn:", err)
-					cl.Close()
+
+					err := cl.Close()
+					if err != nil {
+						log.Printf("Unable to close connection: %s", err)
+					}
+
 					return
 				}
 			}

utils/utils.go

@@ -176,7 +176,10 @@ func GetRandomPortInRange(listenAddr string, portRange string) uint32 {
 		return GetRandomPortInRange(listenAddr, portRange)
 	}
 
-	ln.Close()
+	err = ln.Close()
+	if err != nil {
+		log.Println("Error closing listener:", err)
+	}
 
 	return bindPort
 }
@@ -742,7 +745,10 @@ func GetOpenPort(addr string, port uint32, state *State, sshConn *SSHConnection,
 				if listenErr != nil {
 					err = listenErr
 				} else {
-					ln.Close()
+					err := ln.Close()
+					if err != nil {
+						log.Println("Error closing listener:", err)
+					}
 				}
 			}