-----Original Message-----
From: owner-spf-discuss(_at_)v2(_dot_)listbox(_dot_)com
[mailto:owner-spf-discuss(_at_)v2(_dot_)listbox(_dot_)com]On Behalf Of Mark
Sent: Wednesday, December 01, 2004 12:05 PM
To: spf-discuss(_at_)v2(_dot_)listbox(_dot_)com
Subject: RE: [spf-discuss] Multiple header entries
-----Original Message-----
From: owner-spf-discuss(_at_)v2(_dot_)listbox(_dot_)com
[mailto:owner-spf-discuss(_at_)v2(_dot_)listbox(_dot_)com] On Behalf Of
Richard Bang
Sent: woensdag 1 december 2004 11:05
To: spf-discuss(_at_)v2(_dot_)listbox(_dot_)com
Subject: [spf-discuss] Multiple header entries
Hi,
What should be the policy if an MTA received a message with
an spf header already in it. Should it remove the header and add
its own, or just add a new one and leave the original intact.
(I would assume the latter as it makes the processing history
more intact).
The 'official' status of the SPF-Received: header is a bit in limbo, I
believe. But like regular Received: headers, you could follow
the practice
of adding one 'on top', and leave the older ones be; like so:
Received-SPF: pass (asarian-host.net: domain of
listbox+trampoline+735+865569+5f71ec8d(_at_)v2(_dot_)listbox(_dot_)com
designates
207.8.214.5 as permitted sender)
Received-SPF: pass (backbone.midwestcs.com: domain of midwestcs.com
designates 206.222.212.237 as permitted sender)
client-ip=206.222.212.237;
envelope-from=wayne(_at_)midwestcs(_dot_)com; helo=midwestcs.com;
Adding the hostname of the receiving machine ($j in sendmail)
right after
the first bracket makes for an easy history trail.
- Mark
But if one was not using SPF to do SMTP time rejection, but using the header in
a scoring technique
(like spamassassin) isn't that likely to cause a problem, e.g. when your SPF
check failed, but the
spammer stuck in a fake SPF pass header line: The fake pass could negate the
real fail, or the real
fail could even be superceded by the fake pass.
I would be more of a proponent of something like renaming the existing
Received-SPF to
Old-Received-SPF.
Terry Fielder
Manager Software Development and Deployment
Great Gulf Homes / Ashton Woods Homes
terry(_at_)greatgulfhomes(_dot_)com
Fax: (416) 441-9085
System Administrator Asarian-host.org
---
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we wouldn't call it code." - FedEx
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