From 7398cd6a65bb061dcb9df9d47045e692fee41a46 Mon Sep 17 00:00:00 2001
From: mark van tilburg <markvantilburg@gmail.com>
Date: Mon, 30 Sep 2024 17:34:40 +0200
Subject: [PATCH] Update SpfCheck.cs

Check if the domain just has one spf record. See: https://datatracker.ietf.org/doc/html/rfc4408#section-3.1.2
---
 BusinessMonitor.MailTools/Spf/SpfCheck.cs | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/BusinessMonitor.MailTools/Spf/SpfCheck.cs b/BusinessMonitor.MailTools/Spf/SpfCheck.cs
index 632ec7a..f7ca3e0 100644
--- a/BusinessMonitor.MailTools/Spf/SpfCheck.cs
+++ b/BusinessMonitor.MailTools/Spf/SpfCheck.cs
@@ -79,6 +79,11 @@ private SpfRecord GetRecord(string domain)
                 throw new SpfNotFoundException("No SPF record found on domain");
             }
 
+            if (record.Length > 1)
+            {
+                throw new SpfNotFoundException("Too many SPF records found on domain");
+            }
+            
             // Parse and validate the record and return it
             var parsed = ParseSpfRecord(record);