v1.0.3 : updateCache have its own connection, minor msg modeling and error check

mynettcptable.go

@@ -26,7 +26,7 @@ import (
 )
 
 const (
-	version = "1.0.0-rc2"
+	version = "1.0.3"
 )
 
 var (
@@ -176,6 +176,8 @@ func handleConnection(connClt net.Conn, conLdap *ldap.Conn) {
 			// Dont notice if client closed connection
 			if err.Error() != "EOF" && !strings.HasSuffix(err.Error(), "i/o timeout") {
 				logstream.Errorf("Error reading connection: %v\n", err.Error())
+			} else {
+				logstream.Debug("Error reading on connection : %s", err.Error())
 			}
 			return
 		}
@@ -227,7 +229,12 @@ func handleConnection(connClt net.Conn, conLdap *ldap.Conn) {
 		// First query netCache built with ipNetworkNumber
 		res, err := isIPContainedInNetCache(ip)
 		if err != nil {
-			logstream.Error(err.Error())
+			if strings.EqualFold(err.Error(), fmt.Sprintf("Invalid IP: %s", ip)) {
+				// We don't want those msg to pollute logs
+				logstream.Info(err.Error())
+			} else {
+				logstream.Error(err.Error())
+			}
 			sendResponse(connClt, err.Error(), 500)
 			continue
 		}
@@ -271,22 +278,29 @@ func sendResponse(con net.Conn, respMsg string, respCode int) error {
 	return nil
 }
 
+// attempt is useless now. It was introduced to break after N attempts, but this is not implemented. Should it be?
 func searchLdap(searchReq *ldap.SearchRequest, attempt int) (*ldap.SearchResult, error) {
 	mutex.Lock()
 	result, err := conLdap.Search(searchReq)
 	mutex.Unlock()
 	// Let's just manage connection errors here
-	if err != nil && strings.HasSuffix(err.Error(), "ldap: connection closed") {
-		logstream.Error("LDAP connection closed, retrying")
-		mutex.Lock()
-		conLdap.Close()
-		conLdap, err = connectLdap()
-		mutex.Unlock()
-		if err != nil {
-			return result, err
-		} else {
-			attempt = attempt + 1
-			return searchLdap(searchReq, attempt)
+	if err != nil {
+		if strings.HasSuffix(err.Error(), "ldap: connection closed") || err == ldap.ErrNilConnection {
+			logstream.Error("LDAP connection closed, retrying")
+			mutex.Lock()
+			// 16/01/2023: panic: runtime error: invalid memory address or nil pointer dereference
+			// probably bc connection is already closed
+			if conLdap != nil {
+				conLdap.Close()
+			}
+			conLdap, err = connectLdap()
+			mutex.Unlock()
+			if err != nil {
+				return result, err
+			} else {
+				attempt = attempt + 1
+				return searchLdap(searchReq, attempt)
+			}
 		}
 	}
 	return result, err
@@ -297,23 +311,32 @@ func connectLdap() (*ldap.Conn, error) {
 	conLdap, err = ldap.DialURL(*ldapURL)
 	if err != nil {
 		logstream.Errorf("Error dialing LDAP on %s: %v\n", *ldapURL, err)
-		return conLdap, err
+		return nil, err
 	}
 	err = conLdap.Bind(*ldapUser, *ldapPass)
 	if err != nil {
-		logstream.Errorf("Error binding LDAP: ", err)
-		return conLdap, err
+		logstream.Errorf("Error binding LDAP: %s", err)
+		return nil, err
 	}
 	return conLdap, err
 }
 
-// TODO : buildNetCache should have its own LDAP connection
-func periodicallyUpdateCache(conLdap *ldap.Conn) {
+func periodicallyUpdateCache() {
+	myLdap, err := connectLdap()
+	if err != nil {
+		return
+	}
 	// On initialise immediatement le cache
-	buildNetCacheFromIPNetwork(conLdap)
+	buildNetCacheFromIPNetwork(myLdap)
+	myLdap.Close()
 
 	for range time.Tick(time.Second * time.Duration(*refreshInterval)) {
-		buildNetCacheFromIPNetwork(conLdap)
+		myLdap, err := connectLdap()
+		if err != nil {
+			return
+		}
+		buildNetCacheFromIPNetwork(myLdap)
+		myLdap.Close()
 	}
 }
 
@@ -327,7 +350,7 @@ func run() {
 		return
 	}
 
-	go periodicallyUpdateCache(conLdap)
+	go periodicallyUpdateCache()
 
 	// Spawn a go routine for incoming connection
 	for {
@@ -349,7 +372,7 @@ func main() {
 	ldapBaseDN = fs.String("ldapDN", "", "LDAP base DN (also via LDAPDN env var)")
 	ldapUser = fs.String("ldapUser", "", "LDAP user DN (also via LDAPUSER env var)")
 	ldapPass = fs.String("ldapPass", "", "LDAP user password (also via LDAPPASS env var)")
-	pidFilePath = fs.String("pidfile", "/var/run/mynettcptable/mynettcptable.pid", "PID File (also via PIDFILE env var)")
+	pidFilePath = fs.String("pidfile", "", "PID File (also via PIDFILE env var). Creates pidfile only if defined")
 	refreshInterval = fs.Int("refresh", 300, "Net cache update interval in seconds")
 	timeout = fs.Int("timeout", 5, "timeout in seconds")
 	_ = fs.String("config", "", "config file (optional)")
@@ -366,7 +389,7 @@ func main() {
 		return
 	}
 
-	fmt.Printf("MyNetTCPTable v.%s\n", version)
+	fmt.Printf("%s: MyNetTCPTable v.%s listening on %s\n", time.Now().Format(time.RFC3339), version, *listen)
 
 	logstream = logrus.New()
 	level, err := logrus.ParseLevel(*logLevel)
@@ -403,10 +426,12 @@ func main() {
 		logstream.Hooks.Add(hook)
 	}
 
-	if pid, err := pidfile.Create(*pidFilePath); err != nil {
-		logstream.Fatal(err)
-	} else {
-		defer pid.Clear()
+	if len(*pidFilePath) > 0 {
+		if pid, err := pidfile.Create(*pidFilePath); err != nil {
+			logstream.Fatal(err)
+		} else {
+			defer pid.Clear()
+		}
 	}
 
 	logstream.Infof("Start listening for incoming connections on %s\n", *listen)