From 7e882df929c56acc243b2f20edf080a4597e40d7 Mon Sep 17 00:00:00 2001
From: tipstrade <john.bayly@tipstrade.net>
Date: Mon, 5 Nov 2018 17:07:15 +0000
Subject: [PATCH] Fix prefix check as per MySql bug report 93073

See https://bugs.mysql.com/bug.php?id=93073
---
 MySQL.Data/src/Authentication/MySQLAuthenticationPlugin.cs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/MySQL.Data/src/Authentication/MySQLAuthenticationPlugin.cs b/MySQL.Data/src/Authentication/MySQLAuthenticationPlugin.cs
index 56448a24..0c5ede0d 100644
--- a/MySQL.Data/src/Authentication/MySQLAuthenticationPlugin.cs
+++ b/MySQL.Data/src/Authentication/MySQLAuthenticationPlugin.cs
@@ -247,10 +247,10 @@ private void ContinueAuthentication(byte[] data = null)
         _driver.SendPacket(packet);
 
         packet = ReadPacket();
+        // Is it MySQL protocol (0=OK or 254=need old password) packet ?
         byte prefixByte = packet.Buffer[0];
-        if (prefixByte != 1) return;
+        if (prefixByte == 0 || prefixByte == 254) return;
 
-        // A prefix of 0x01 means need more auth data.
         byte[] responseData = new byte[packet.Length - 1];
         Array.Copy(packet.Buffer, 1, responseData, 0, responseData.Length);
         moreData = MoreData(responseData);