introduce smtp config option for EHLO identity

pkg/services/notifications/mailer.go

@@ -101,7 +101,11 @@ func createDialer() (*gomail.Dialer, error) {
 
 	d := gomail.NewDialer(host, iPort, setting.Smtp.User, setting.Smtp.Password)
 	d.TLSConfig = tlsconfig
-	d.LocalName = setting.InstanceName
+	if setting.Smtp.EhloIdentity != "" {
+		d.LocalName = setting.Smtp.EhloIdentity
+	} else {
+		d.LocalName = setting.InstanceName
+	}
 	return d, nil
 }
 

pkg/setting/setting_smtp.go

@@ -1,15 +1,16 @@
 package setting
 
 type SmtpSettings struct {
-	Enabled     bool
-	Host        string
-	User        string
-	Password    string
-	CertFile    string
-	KeyFile     string
-	FromAddress string
-	FromName    string
-	SkipVerify  bool
+	Enabled      bool
+	Host         string
+	User         string
+	Password     string
+	CertFile     string
+	KeyFile      string
+	FromAddress  string
+	FromName     string
+	EhloIdentity string
+	SkipVerify   bool
 
 	SendWelcomeEmailOnSignUp bool
 	TemplatesPattern         string
@@ -25,6 +26,7 @@ func readSmtpSettings() {
 	Smtp.KeyFile = sec.Key("key_file").String()
 	Smtp.FromAddress = sec.Key("from_address").String()
 	Smtp.FromName = sec.Key("from_name").String()
+	Smtp.EhloIdentity = sec.Key("ehlo_identity").String()
 	Smtp.SkipVerify = sec.Key("skip_verify").MustBool(false)
 
 	emails := Cfg.Section("emails")