Specific From and To check rule

[Glenn Steen]

On 15/08/06, Alex Neuman van der Hans <alex at nkpanama.com> wrote:
> Feasey, Nicholas wrote:
> > Forgive me if this has been discussed before...
> >
> > Is there a simple method in which MailScanner can be told to check the
> >>From and the To address and, if it's from the same person, reject it.
> >
> > I want to stop those messages that state:
> >
> > From:  <someuser>@<somedomain.com>
> > To:    <someuser>@<somedomain.com>
> >
> > ...which are really annoying.
> >
> > N
> Create a ruleset:
> in %rules-dir%/spam.blacklist.rules
>
> FromOrTo:       default         no
> From:user1 at domain.com   and     To:user1 at domain.com     yes
> ...
> ...
> ...
> From:user99 at domain.com  and     To:user99 at domain.com    yes
>
> Sounds silly, and resource-wasteful, but it should get the job done, I
> think.

That should work splendidly, but... I handle this type of thing in the
MTA, so that I can reject the message (not handling a bogus message is
always better than accepting (the responsibility for it) and having to
handle it). You might not be able to do exactly this in your MTA (I
use Postfix), but something similar...
For example:
 I reject all mail with an envelope  sender looking to be from our
domain, and  place that restriction so that the permit_mynetworks
"restriction" overrides it. Then I also reject all unknown recipients.
Takes care of a lot, if not all, of these messages, since they can
only send to real recipients in my domain but cannot claim to be
sending it from that domain, unless the sender is really sending it
from the allowed servers.
This might not work that well with roadrunners though:-)
-- 
-- Glenn
email: glenn < dot > steen < at > gmail < dot > com
work: glenn < dot > steen < at > ap1 < dot > se