Re: [Asrg] misconception in SPF

Chris Lewis <clewis+ietf@mustelids.ca> Mon, 10 December 2012 20:09 UTC

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Date: Mon, 10 Dec 2012 15:09:00 -0500
From: Chris Lewis <clewis+ietf@mustelids.ca>
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Subject: Re: [Asrg] misconception in SPF
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On 12-12-10 12:00 PM, Christian Grunfeld wrote:

> you get no answer because there is not SPF record for www.google.com,
> so you can forge emails as if they come from www.google.com even if
> there exists an SPF record for google.com !

The point was about your #2.  Those using ?all.  Eg: you.

People don't use !all, for the same reason gmail (you) uses ?all.

With that huge problem in the way, trying to solve <hostname>.<spf'd
name> doesn't seem very useful.

The "solution" of publishing SPF records for all A'd hosts works
sometimes, but sometimes it just doesn't scale.

Just imagine how many hostnames that Google and Gmail have between them.