Re: [yam] Interop problem: SMTP submission, STARTTLS, AUTH EXTERNAL

"John R. Levine" <johnl@iecc.com> Sat, 01 May 2010 01:42 UTC

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From: "John R. Levine" <johnl@iecc.com>
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Subject: Re: [yam] Interop problem: SMTP submission, STARTTLS, AUTH EXTERNAL
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> Comments?

This is hardly the only case where the client and server both know that 
it's OK to relay, even though there's nothing in the SMTP dialog to 
confirm it. Why should implicit auth via STARTTLS be any different than 
implicit AUTH by connecting from a friendly IP address or implicit auth by 
POP-before-SMTP?

I suppose we could allow the second EHLO to say RELAY to tell the client 
that it's OK to relay, but it's hard to see how this would be useful since 
the existing practice is that the client just sends the message, and the 
server lets it know if there's a problem.

Regards,
John Levine, johnl@iecc.com, Primary Perpetrator of "The Internet for Dummies",
Information Superhighwayman wanna-be, http://www.johnlevine.com, ex-Mayor
"More Wiener schnitzel, please", said Tom, revealingly.