[Esd-l] Trust local network for smart reply

John D. Hardin jhardin at impsec.org
Tue Mar 9 17:51:57 PST 2004


On Tue, 9 Mar 2004, Fabio Invernizzi wrote:

> >NOTICE: Envelope sender domain inter.it not supported by Received:
> >path. Suppressing sender notification.
 
> And the Received: header in the quarantined email:
> >From giovanni.xyz at inter.it  Tue Mar  9 17:07:25 2004
> >Received: from giovanni (unknown [10.39.2.158])
> >        by s2.inter.it (Postfix) with SMTP id 7095CEDF5
> >        for <fabio.invernizzi at inter.it>; Tue,  9 Mar 2004 17:07:19

> How can I trust my local network?

The "unknown" in the Received: header needs to have the domain in it,
so you'll either need to do internal DNS entries or possibly
/etc/hosts entries on the mailserver. The reverse lookup on the
client's IP address needs to return useful information (a FQDN that
supports the sender's email domain).

e.g., an /etc/hosts entry on the mail server:

   10.39.2.158	giovanni.inter.it

If they're assigned using DHCP, don't assign specific names:

   10.39.2.158  lnet-158.inter.it

--
 John Hardin KA7OHZ    ICQ#15735746    http://www.impsec.org/~jhardin/
 jhardin at impsec.org    FALaholic #11174    pgpk -a jhardin at impsec.org
 key: 0xB8732E79 - 2D8C 34F4 6411 F507 136C  AF76 D822 E6E6 B873 2E79
-----------------------------------------------------------------------
  "Bother," said Pooh as he struggled with /etc/sendmail.cf, "it never
  does quite what I want. I wish Christopher Robin was here."
				-- Peter da Silva in a.s.r
-----------------------------------------------------------------------
   25 days until the Slovakian Presidential Election


More information about the esd-l mailing list