From 07ad9fc557588c894839daaf4dc66d9d17ab83a3 Mon Sep 17 00:00:00 2001
From: Ben Origas <borigas@ocuvera.com>
Date: Wed, 15 Apr 2020 09:55:23 -0500
Subject: [PATCH] Add exception if both Certificate and X509Certificate are set

---
 Source/MQTTnet/Implementations/MqttTcpServerAdapter.cs | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/Source/MQTTnet/Implementations/MqttTcpServerAdapter.cs b/Source/MQTTnet/Implementations/MqttTcpServerAdapter.cs
index 8bc03904..25879bfd 100644
--- a/Source/MQTTnet/Implementations/MqttTcpServerAdapter.cs
+++ b/Source/MQTTnet/Implementations/MqttTcpServerAdapter.cs
@@ -48,6 +48,10 @@ namespace MQTTnet.Implementations
                 {
                     throw new ArgumentException("TLS certificate is not set.");
                 }
+                else if (options.TlsEndpointOptions.Certificate != null && options.TlsEndpointOptions.X509Certificate != null)
+                {
+                    throw new ArgumentException($"{nameof(MqttServerTlsTcpEndpointOptions.Certificate)} and {nameof(MqttServerTlsTcpEndpointOptions.X509Certificate)} cannot both be set");
+                }
 
                 X509Certificate2 tlsCertificate;
                 if (options.TlsEndpointOptions.X509Certificate != null)