[RE: educating rDNS violators]

[Pat Moffitt <pmoffitt () wrv com>]

I am not attempting to verify the HELO Command.  I am attempting to verify the 
IP Address of the system that is trying to make the SMTP connection.  As such, 
this section of the RFC does not apply.  I see nothing in this RFC that applies 
to using RDNS to reject mail connections, only on using RDNS to verify HELO 
commands.

Pat Moffitt
MIS Administrator
Western Recreational Vehicles, Inc.


-------- Original Message --------
Subject: RE: educating rDNS violators
Date: Tue, 31 Aug 2004 13:35:34 -0400
From: LordInfidel () directionweb com
To: 'Derek Schaible' <dschaible () cssiinc com>,        Niek <niek () packetstorm nu>
CC: security-basics () securityfocus com

[snip - to supply the relevent part of the message]

6. Section 5.2.5 of rfc1123 covers this quite explicitly.  Rejecting mail
based on RDNS ~~~***VIOLATES***~~~ the RFC:
http://www.faqs.org/rfcs/rfc1123.html

5.2.5  HELO Command: RFC-821 Section 3.5

[snip]

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