[Mimedefang] Curious about a couple of things in mimedefang-filter

[Nels Lindquist]

On 12 Aug 2002 at 13:20, Jim McCullars wrote:

> On Mon, 12 Aug 2002, David F. Skoll wrote:
> 
> > > Second question:  Is it possible to get the string that the sending MTA
> > > sends as the HELO value?
> >
> > Not from the Perl filter, although it is available via libmilter.
> > I can add this if you like.
> 
>    That would be great!  Especially if it was available at the beginning
> like filter_relay (or maybe even as a third argument to filter_relay).  I
> can't tell you how many spams I get with a Received: header like this:
> 
> ^Received: from info.uah.edu ([some IP that is overseas]) ...
> 
> and I would love to reject them immediately (if they are not indeed
> info.uah.edu calling).

Mismatches between the SMTP HELO string and the DNS PTR record are 
very common.  Heck, mismatches between the DNS A record and the DNS 
PTR record are pretty common--assuming the PTR record exists at all.  
Multiple domains may be hosted on one IP address, virtual hosts may 
not announce themselves properly, and so on.  I think you'd end up 
rejecting a lot of legitimate mail that way.

----
Nels Lindquist <*>
Information Systems Manager
Morningstar Air Express Inc.