Fix ldapAttr typo

mxrouter.conf.sample

@@ -6,5 +6,5 @@ ldapPass here_lies_the_password
 # "domain" sera ajoute a relayName pour former le FQDN
 domain example.org
 # Le nom de l'attribut LDAP contenant le relais a retourner
-lapAttr relayName
+ldapAttr relayName
 

mxrouter.go

@@ -10,6 +10,7 @@
 // Use a single LDAP connection protected by a mutex
 //
 // v0.9.6 : add PID file
+// v0.9.8 : Check MX format with regex
 //
 
 package main
@@ -21,8 +22,10 @@ import (
 	"log/syslog"
 	"net"
 	"os"
+	"regexp"
 	"strings"
 	"sync"
+	"time"
 
 	"github.com/go-ldap/ldap/v3"
 	"github.com/peterbourgon/ff"
@@ -30,7 +33,10 @@ import (
 )
 
 const (
-	version = "0.9.6"
+	version = "0.9.9"
+	// Match le nom de domaine, soit les 2 dernieres chaines separees par un point.
+	//  Peut aussi terminer par un point (Ex: srv.domaine.com. => domaine.com)
+	DomainRegexpFormat = `([0-9A-Za-z\-]*)\.([0-9A-Za-z\-]*)(?:\.)?$`
 )
 
 var (
@@ -46,14 +52,17 @@ var (
 	ldapAttr    *string
 	defDomain   *string
 	pidFilePath *string
+	timeout     *int
 )
 
+// attempt is useless now. It was introduced to break after N attempts, but this is not implemented. Should it be?
 func ldapSearch(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") {
+	if err != nil {
+		if strings.HasSuffix(err.Error(), "ldap: connection closed") {
 			logstream.Err("LDAP connection closed, retrying")
 			mutex.Lock()
 			conLdap.Close()
@@ -65,20 +74,63 @@ func ldapSearch(searchReq *ldap.SearchRequest, attempt int) (*ldap.SearchResult,
 				attempt = attempt + 1
 				return ldapSearch(searchReq, attempt)
 			}
+		} else if err == ldap.ErrNilConnection {
+			logstream.Err("LDAP connection is nil, reconnecting")
+			mutex.Lock()
+			// conLdap is nil so this would be a sigsegv/panic
+			//conLdap.Close()
+			conLdap, err = connectLdap()
+			mutex.Unlock()
+			if err != nil {
+				return result, err
+			} else {
+				attempt = attempt + 1
+				return ldapSearch(searchReq, attempt)
+			}
+		}
 	}
 
 	return result, err
 }
 
+func sendResponse(con net.Conn, respMsg string, respCode int) error {
+	response := fmt.Sprintf("%d %s\n", respCode, strings.Replace(respMsg, " ", "%20", -1))
+	_, err := con.Write([]byte(response))
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
 func handleConnection(connClt net.Conn, conLdap *ldap.Conn) {
 	var s string
 	var mxdom string
+
 	buf := make([]byte, 1024)
 
-	defer connClt.Close()
+	re := regexp.MustCompile(DomainRegexpFormat)
+
+	// Close connection when this function ends
+	defer func() {
+		logstream.Debug("Closing connection")
+		connClt.Close()
+	}()
+
+	timeoutDuration := time.Duration(*timeout) * time.Second
+
+	for {
+		// Set a deadline for reading. Read operation will fail if no data
+		// is received after deadline.
+		connClt.SetReadDeadline(time.Now().Add(timeoutDuration))
+
 		readlen, err := connClt.Read(buf)
 		if err != nil {
-		fmt.Println("Error reading:", err.Error())
+			// Dont notice if client closed connection
+			if err.Error() != "EOF" && !strings.HasSuffix(err.Error(), "i/o timeout") {
+				logstream.Err(fmt.Sprintln("Error reading connection :", err.Error()))
+			}
+			return
 		}
 
 		// 1) Recupere le MX du domaine de l'adresse mail recue
@@ -88,29 +140,29 @@ func handleConnection(connClt net.Conn, conLdap *ldap.Conn) {
 			mxs, err := net.LookupMX(domain)
 			if err != nil {
 				logstream.Err(fmt.Sprintln("Error lookup mx: ", err))
-			s := strings.Replace(fmt.Sprintf("Error lookup MX: %s", err.Error()), " ", "%20", -1)
-			response := fmt.Sprintf("500 %s\n", s)
-			connClt.Write([]byte(response))
-			return
+				s := fmt.Sprintf("Error lookup MX: %s", err.Error())
+				sendResponse(connClt, s, 500)
+				continue
 			}
 			// 2) Requete LDAP pour voir si le domaine de second niveau du MX possede un routage particulier
 			// Protection contre ca : example.org.            72      IN      MX      0 .
 			// Considerons qu'il n'y aura jamais de "one letter TLD"
 			if len(mxs[0].Host) < 4 {
 				logstream.Err(fmt.Sprintln("No usable mx found"))
-			s := strings.Replace("No usable MX found", " ", "%20", -1)
-			resp := fmt.Sprintf("500 %s\n", s)
-			connClt.Write([]byte(resp))
-			return
+				s := "No usable MX found"
+				sendResponse(connClt, s, 500)
+				continue
 			}
 
-		mxslic := strings.Split(mxs[0].Host, ".")
-		// les MXs terminent par '.', on le retire
-		if mxs[0].Host[len(mxs[0].Host)-1] == '.' {
-			mxdom = strings.Join(mxslic[len(mxslic)-3:len(mxslic)-1], ".")
-		} else {
-			mxdom = strings.Join(mxslic[len(mxslic)-2:len(mxslic)], ".")
+			// On recuperer le nom de domaine de 1er niveau
+			group := re.FindSubmatch([]byte(mxs[0].Host))
+			if len(group) < 3 || len(group[2]) == 0 {
+				logstream.Err(fmt.Sprintln("MX format incorrect: ", mxs[0].Host))
+				s := fmt.Sprintf("MX format incorrect: %s", mxs[0].Host)
+				sendResponse(connClt, s, 500)
+				continue
 			}
+			mxdom = string(group[1]) + "." + string(group[2])
 
 			filter := fmt.Sprintf("(dc=%s)", ldap.EscapeFilter(mxdom))
 			searchReq := ldap.NewSearchRequest(*ldapBaseDN, ldap.ScopeWholeSubtree, 0, 0, 0,
@@ -119,29 +171,26 @@ func handleConnection(connClt net.Conn, conLdap *ldap.Conn) {
 			result, err := ldapSearch(searchReq, 0)
 			if err != nil {
 				logstream.Err(fmt.Sprintln("Error searching into LDAP: ", err))
-			s := strings.Replace(err.Error(), " ", "%20", -1)
-			response := fmt.Sprintf("500 %s\n", s)
-			connClt.Write([]byte(response))
-			return
+				s := err.Error()
+				sendResponse(connClt, s, 500)
+				continue
 			}
 
 			if len(result.Entries) != 1 {
 				if *debug {
 					logstream.Debug("Got no result, returning 500")
 				}
-			s := strings.Replace("No route defined", " ", "%20", -1)
-			response := fmt.Sprintf("500 %s\n", s)
-			connClt.Write([]byte(response))
-			return
+				s := "No route defined"
+				sendResponse(connClt, s, 500)
+				continue
 			}
 
 			// L'attribut n'existe pas
 			if len(result.Entries[0].Attributes) == 0 {
 				logstream.Err(fmt.Sprintf("Error searching into LDAP: Attribute %s not found for entry %s\n", *ldapAttr, result.Entries[0]))
-			s := strings.Replace(fmt.Sprintf("Attribute not found: %s", *ldapAttr), " ", "%20", -1)
-			response := fmt.Sprintf("500 %s\n", s)
-			connClt.Write([]byte(response))
-			return
+				s := fmt.Sprintf("Attribute not found: %s", *ldapAttr)
+				sendResponse(connClt, s, 500)
+				continue
 			}
 
 			if *debug {
@@ -149,19 +198,19 @@ func handleConnection(connClt net.Conn, conLdap *ldap.Conn) {
 			}
 			// Check if result is a FQDN, if not append defDomain
 			if strings.Contains(string(result.Entries[0].Attributes[0].Values[0]), ".") {
-			s = strings.Replace(fmt.Sprintf("FILTER relay:[%s]", result.Entries[0].Attributes[0].Values[0]), " ", "%20", -1)
+				s = fmt.Sprintf("FILTER relay:[%s]", result.Entries[0].Attributes[0].Values[0])
 			} else {
-			s = strings.Replace(fmt.Sprintf("FILTER relay:[%s]", fmt.Sprintf("%s.%s", result.Entries[0].Attributes[0].Values[0], *defDomain)), " ", "%20", -1)
+				s = fmt.Sprintf("FILTER relay:[%s]", fmt.Sprintf("%s.%s", result.Entries[0].Attributes[0].Values[0], *defDomain))
 			}
-		connClt.Write([]byte(fmt.Sprintf("200 %s\n", s)))
+			sendResponse(connClt, s, 200)
 		} else {
 			if *debug {
 				logstream.Debug("Incorrect input format : " + string(buf[:readlen-1]))
 			}
-		s := strings.Replace("Incorrect input format", " ", "%20", -1)
-		response := fmt.Sprintf("500 %s\n", s)
-		connClt.Write([]byte(response))
-		return
+			s := "Incorrect input format"
+			sendResponse(connClt, s, 500)
+			continue
+		}
 	}
 }
 
@@ -218,6 +267,7 @@ func main() {
 	ldapAttr = fs.String("ldapAttr", "relayName", "LDAP attribute containing the relay name to return")
 	defDomain = fs.String("domain", "", "Domain to add to relay name if not a FQDN (also via DOMAIN env var)")
 	pidFilePath = fs.String("pidfile", "/var/run/mxrouter/mxrouter.pid", "PID File (also via PIDFILE env var)")
+	timeout = fs.Int("timeout", 5, "timeout in seconds")
 	_ = fs.String("config", "", "config file (optional)")
 
 	// Surcharge de la fonction Usage()