fixed when an MX refereneces an MX

Makefile

@@ -1,7 +1,7 @@
 ROOT_DIR:=$(shell dirname $(realpath $(lastword $(MAKEFILE_LIST))))
 
 BINARY=mxcheck
-VERSION=1.4.1
+VERSION=1.4.2
 
 BUILD=`git rev-parse --short HEAD`
 PLATFORMS=darwin linux windows

README.md

@@ -27,7 +27,7 @@ You can set mailFrom, mailTo, the DNS server, DKIM selector and output a report
 
 # Version
 
-v1.4.1
+v1.4.2
 
 [![Go Report Card](https://goreportcard.com/badge/github.com/steffenfritz/mxcheck)](https://goreportcard.com/report/github.com/steffenfritz/mxcheck) 
 [![Go Reference](https://pkg.go.dev/badge/github.com/steffenfritz/mxcheck.svg)](https://pkg.go.dev/github.com/steffenfritz/mxcheck)

dns.go

@@ -60,6 +60,12 @@ func getA(targetHostName string, dnsServer string) (string, error) {
 
 	if t, ok := in.Answer[0].(*dns.A); ok {
 		a = t.A.String()
+		// We check for a second ip address when the first entry is also an mx entry.
+		// We also have to update the targetHost because of the cwrt test in openrelay
+	} else {
+		if t, ok := in.Answer[1].(*dns.A); ok {
+			a = t.A.String()
+		}
 	}
 
 	return a, err

mxcheck.1

@@ -22,7 +22,7 @@
 .\" %%%LICENSE_END
 
 
-.TH mxcheck 1 "November 2022" "version 1.4.1"
+.TH mxcheck 1 "November 2022" "version 1.4.2"
 
 .SH NAME
 mxcheck

openrelay.go

@@ -7,6 +7,7 @@ import (
 	"log"
 	"net"
 	"net/smtp"
+	"strings"
 	"time"
 )
 
@@ -61,7 +62,8 @@ func openRelay(mailFrom string, mailTo string, targetHost string) (openResult, e
 		// update config to ignore invalid TLS certificates and proceed
 		tlsconfig = &tls.Config{InsecureSkipVerify: true}
 		err = c.StartTLS(tlsconfig)
-		if err == nil {
+		// As there are no error types returned by the TLS client we need this ugly or. Should be fixed with a switch
+		if err == nil || strings.HasSuffix(err.Error(), "certificate name does not match input") {
 			or.tlsbool = true
 			or.tlsvalid = false
 		}