Re: [Uta] General question on draft-ietf-uta-mta-sts-03
Viktor Dukhovni <ietf-dane@dukhovni.org> Mon, 03 April 2017 13:39 UTC
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From: Viktor Dukhovni <ietf-dane@dukhovni.org>
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Date: Mon, 03 Apr 2017 09:38:58 -0400
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Subject: Re: [Uta] General question on draft-ietf-uta-mta-sts-03
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> On Apr 3, 2017, at 5:23 AM, <Gerard.DRAPER-GIL@ec.europa.eu> <Gerard.DRAPER-GIL@ec.europa.eu> wrote: > > Regarding the policy validation, would't the use of DNSSEC fix both the > validation and update on demand problem? Quite so, but with DNSSEC you don't need STS, just use DANE. > In the SAN vs MX discussion, if I'm not wrong, the discussion is > either to use the mx parameter from the policy to filter MX > hostnames, or to use it to filter against the SAN within the > certificate received. Yes, possibly renamed if ceases to be an MX hostname filter. > Since the section 4.2 (https://tools.ietf.org/html/draft-ietf-uta-mta-sts-03#section-4.2) defines that "... presented by the receiving MX MUST be valid for the MX hostname and chain to a root CA that is trusted by the sending MTA ...", the result of any of the two options would be the same (we assume that an attacker cannot forge a certificate that would pass certificate validation). That text would also change if the policy admits other matching names. > But, using the mx parameter to filter the MX records, would create > somehow an alternative way of discovering the list of MX for a domain, No, it is an authenticated cached *filter* on the data obtained from DNS, and supports wildcards, which means that you don't actually get the MX hostnames from the policy. -- Viktor.
- [Uta] General question on draft-ietf-uta-mta-sts-… Gerard.DRAPER-GIL
- Re: [Uta] General question on draft-ietf-uta-mta-… Daniel Margolis
- Re: [Uta] General question on draft-ietf-uta-mta-… Gerard.DRAPER-GIL
- Re: [Uta] General question on draft-ietf-uta-mta-… Viktor Dukhovni