[Mimedefang] $Sender Problem

[Dave O'Neill]

On Fri, Feb 05, 2010 at 03:35:30PM -0500, Kevin A. McGrail wrote:
> I'm running some tests on $Sender in my filter.  One of my logics ran  
> awry today because I guess I was expecting the From: header value but  
> instead got the Return-Path value.

$Sender will always be the envelope sender (the address presented at 
MAIL FROM time), not any address parsed from the headers.

> This appears to be SRS http://www.openspf.org/SRS so that the email doesn't run afoul of SPS.
>
> Luckily, my emails are going through a Sanitize routine so I should be 
> able to seamlessly wedge a de-SRS routine into the mix.  That looks to 
> point to something like http://search.cpan.org/dist/Mail-SRS/
>
> Anyone ever run across this?

Yes, but there's no guarantee that their SRS encoding will be reversible 
enough for you to recover the original address.  The spec for the srs0 
format doesn't require that anyone but the relaying party be able to 
decode the localpart to obtain the original sender.

srs1 does require that the original sender be retrievable by third 
parties, and in practice many srs0 implementations do as well, so you 
can probably de-SRS most of them, but you can't rely on it working 100% 
of the time.

Cheers,
Dave
-- 
Dave O'Neill <dmo at roaringpenguin.com>    Roaring Penguin Software Inc.
+1 (613) 231-6599                        http://www.roaringpenguin.com/
For CanIt technical support, please mail: support at roaringpenguin.com