spf-discuss
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Re: Sendmail white paper, SRS, and forwarding

2004-11-21 13:02:51
On Sun, 2004-11-21 at 20:30 +0100, Roger Moser wrote:
I don't understand why this mail would be rejected. Unless it's just
rejected due to the normal brokenness of SPF when mail is forwarded?

forwarder1.com sends it to forwarder2.com saying
MAIL 
FROM:<SRS0=HHH=TT=forwarder1(_dot_)com=XXXXXXX=name(_at_)forwarder1(_dot_)com>

i.e. MAIL FROM:<anything(_at_)f1(_dot_)com>

forwarder2.com sends it to final.com saying
MAIL 
FROM:<SRS0=HHH=TT=forwarder1(_dot_)com=XXXXXXX=name(_at_)forwarder1(_dot_)com>

i.e. MAIL FROM:<anything(_at_)f1(_dot_)com>

final.com checks SPF and gets the result "Fail". Since the return-path is
not signed, it rejects the mail.

Right. Just a normal example of the brokenness of SPF. This isn't really
related to SES at all. If f1.com was stupid enough to publish an SPF '-
all' record AND final.com is stupid enough to obey it, valid mail gets
lost. This is nothing new.

-- 
dwmw2