From mboxrd@z Thu Jan  1 00:00:00 1970
From: bakul@bitblocks.com (Bakul Shah)
Date: Wed, 20 Sep 2017 16:57:13 -0700
Subject: [TUHS] Who is running their own mail server and what do you run?
In-Reply-To: Your message of "Wed, 20 Sep 2017 23:54:34 +0100."
 <1274eb5fe2051d0052af14155ba75a0a@quintile.net>
References: <1274eb5fe2051d0052af14155ba75a0a@quintile.net>
Message-ID: <20170920235713.1BED6156E523@mail.bitblocks.com>

What is needed  is an SMTP "Brita" filter!

  crud+legit email => smtp filter => legit email

This then goes to your usual MTA. Steve, this may be
the killer app for plan9!

On Wed, 20 Sep 2017 23:54:34 +0100 "Steve Simon" <steve at quintile.net> wrote:
"Steve Simon" writes:
> My spam filtering is all plan9 based but the ideals are all portable.
> 
> Greylisting and delaying a few secs before starting the SMTP
> conversation are my most successful filters, After this comes
> SPF and using spamhaus to validate the senders IP.
> 
> I reject some silly domains like localhost.com and usernames like
> user and test.
> 
> I also have a list of regexps which match the reverse dns
> addresses of adsl blocks which catch many spam bots.
> 
> The regexps sound like a lot of work but I have some scripts to
> analyse my logs and suggest  patterns, so its just a click or two
> I can block somthing like:
> 
> 	dhcp.[0-9]+.[0-9]+.[0-9]+.[0-9]+.adsl.nasty-isp.net
> 
> -Steve