Reminds me of these two plugins:
https://forums.alliedmods.net/showthread.php?t=255871
https://forums.alliedmods.net/showthread.php?p=2329976
I don't use either of those anymore because, after running one of those for a long time, I found out that it was blocking EVERYONE, and now I'm paranoid about what exactly those plugins do, especially in times when Steam is down.
I also don't have a lot of confidence in whether or not they know it works how it should in every scenario.
hmhm