RE: patch to force helo or ehlo before any smtp command

Hello.

> > ... but since Sendmail MTA required it from the beginning (when the
> > only open source choice was SM), actually every spammer software
> sends
> > HELO (very broken software too).
> 
> You are right. I looked at this issue closely today: Not one spam mail
> without HELO/EHLO.
> 
> > So who you will block with this patch?
> 
> At least there is a low risk for false positives, since Google and so
> do the same...

Well, we do not use that patch but a very similar one which integrates
a Helo/ehlo delay combined with a blacklist and a reject for early-talkers
too.

Analyzing logs and statistics we see thousands of early-talkers per hou and
blacklisted helo/ehlos, but indeed a very small count of no helo/ehlo.
But all these can mostly be connected with Trojan or bot infected clients.

So using a no_helo patch alone will not do so much good, but combining helo/ehlo
related checks make it better.

Greets
Phil.