Re: [ietf-smtp] IETF Policy on dogfood consumption or avoidance - SMTP version
Viktor Dukhovni <ietf-dane@dukhovni.org> Tue, 17 December 2019 19:24 UTC
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From: Viktor Dukhovni <ietf-dane@dukhovni.org>
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Subject: Re: [ietf-smtp] IETF Policy on dogfood consumption or avoidance - SMTP version
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> On Dec 17, 2019, at 2:02 PM, Hector Santos <hsantos=40isdg.net@dmarc.ietf.org> wrote: > > But here is I see it: > > 1) Yes, everyone agree the response text needs to be fixed up, but > > 2) It is in fact a violation of RFC2821/5321 specification when a rejection is applied by a server to a perfectly valid ip-literal per specification, and It is not in fact. A receiving MTA can refuse your email for any reason. As a matter of RFC-compliance it MUST recognize address literals as valid syntax (which it did by returning a 550 rather than 500 or 501), but is then free to reject them on policy grounds. > 3) It lacks consistency in its operational decision on what Client Mail/Host Names are rejected or accepted. This is also not true. It consistently rejects address literals because doing so carries little risk of false positives (as already explained on the ietf-smtp list, where the more technical discussion belongs). "Real" MTAs use domain names. It is as simple as that. > If a rejection is going to apply to ip-literals, hence enforcing a FQDN, then at the very least, it should validate the FQDN. No, because enough "Real" MTAs use HELO domain names that don't map to their own IP address, or any address at all. So the risk of FPs is too high. There is no a priori discrimination here, it is all just based on what one can get away with to reduce spam without blocking a non-trivial volume of legitimate email. > The mail.ietg.org servers appears to accept any FQDN including a existing > FQDN which does not match the connecting IP address and a non-existing FQDNs: As they must for operational reasons. > Yet, it does not validate the FQDN. Why? Because, much as one might want to, too many "Real" MTAs (sending legitimate traffic) have FQDNs that would fail verification. -- Viktor.
- [ietf-smtp] FWD: IETF Policy on dogfood consumpti… John C Klensin
- Re: [ietf-smtp] FWD: IETF Policy on dogfood consu… Hector Santos
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Viktor Dukhovni
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Michael Peddemors
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Keith Moore
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Viktor Dukhovni
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Hector Santos
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Viktor Dukhovni
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Salz, Rich
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Randy Bush
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Hector Santos
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Hector Santos
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Salz, Rich
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… S Moonesamy
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Peter J. Holzer
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Keith Moore
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Viktor Dukhovni
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Russ Allbery
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Brandon Long
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Keith Moore
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Keith Moore
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Hector Santos
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Keith Moore
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Paul Smith
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Paul Smith
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Peter J. Holzer
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Peter J. Holzer
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Peter J. Holzer
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Peter J. Holzer
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Keith Moore
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Keith Moore
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… John Leslie
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Hector Santos
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Peter J. Holzer
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Hector Santos
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Viktor Dukhovni
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Hector Santos
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Viktor Dukhovni
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Keith Moore
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Viktor Dukhovni
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Paul Smith
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Keith Moore
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Alessandro Vesely
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Viktor Dukhovni
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Hector Santos
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Peter J. Holzer
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Dave Crocker
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Peter J. Holzer
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Keith Moore
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Hector Santos
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Keith Moore
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Hector Santos
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Keith Moore
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Russ Allbery
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Jeremy Harris
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Keith Moore
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Sam Varshavchik
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Keith Moore
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Alessandro Vesely
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Keith Moore
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Dave Crocker
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… John C Klensin
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Keith Moore
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… John C Klensin
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Sam Varshavchik
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Dave Crocker
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Keith Moore
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Dave Crocker
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Keith Moore
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Dave Crocker
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Keith Moore
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… John C Klensin
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… John C Klensin
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Sam Varshavchik
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Keith Moore
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Dave Crocker
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Keith Moore
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Dave Crocker
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Keith Moore
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Alessandro Vesely
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Paul Smith
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Sam Varshavchik
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Richard Clayton
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Dave Crocker
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Keith Moore
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Dave Crocker
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Keith Moore
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Dave Crocker
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Keith Moore
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Dave Crocker
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Keith Moore
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Alessandro Vesely
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Sam Varshavchik
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Richard Clayton
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Alessandro Vesely
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Sam Varshavchik
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Keith Moore
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… John C Klensin
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… S Moonesamy
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Alessandro Vesely
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Keith Moore
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Sam Varshavchik
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Keith Moore
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Sam Varshavchik
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… S Moonesamy
- Re: [ietf-smtp] IETF Policy on dogfood consumptio… Sam Varshavchik