Messaging: Make tls version configurable

Messaging/MailSender.vb

@@ -20,10 +20,18 @@ Public Class MailSender
         SslPolicyErrors.RemoteCertificateChainErrors Or ' self-signed
         SslPolicyErrors.RemoteCertificateNameMismatch   ' name mismatch
 
+    Public Class MailSenderOptions
+        Public Property TlsVersion As Security.Authentication.SslProtocols = Security.Authentication.SslProtocols.Default
+    End Class
+
     Public Sub New(pLogConfig As LogConfig)
         MyBase.New(pLogConfig)
     End Sub
 
+    Public Function ConnectToServer(pServer As String, pPort As Integer, pUser As String, pPassword As String, pAuthType As String) As Boolean
+        Return ConnectToServer(pServer, pPort, pUser, pPassword, pAuthType)
+    End Function
+
     ''' <summary>
     ''' Start a connection with the specified server and return the SMTP client. Throws if there was an error.
     ''' </summary>
@@ -33,7 +41,7 @@ Public Class MailSender
     ''' <param name="pPassword"></param>
     ''' <param name="pAuthType"></param>
     ''' <returns></returns>
-    Public Function ConnectToServer(pServer As String, pPort As Integer, pUser As String, pPassword As String, pAuthType As String) As Boolean
+    Public Function ConnectToServer(pServer As String, pPort As Integer, pUser As String, pPassword As String, pAuthType As String, pOptions As MailSenderOptions) As Boolean
         Server = pServer
         Port = pPort
         User = pUser
@@ -51,6 +59,11 @@ Public Class MailSender
 
         Logger.Debug("Initializing Connection with Auth type [{0}].", pAuthType)
 
+        ' Set TLS Version manually if requested
+        If pOptions.TlsVersion <> Security.Authentication.SslProtocols.Default Then
+            oSession.SSLConfiguration.EnabledSslProtocols = pOptions.TlsVersion
+        End If
+
         If pAuthType = "SSL" Then
             Try
                 If pPort = 465 Then