Re: [ietf-smtp] DANE / Fwd: ACTION REQUIRED: Renew these Let's Encrypt certificates by March 4

Viktor Dukhovni <ietf-dane@dukhovni.org> Sun, 08 March 2020 13:42 UTC

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Date: Sun, 8 Mar 2020 09:42:22 -0400
From: Viktor Dukhovni <ietf-dane@dukhovni.org>
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Subject: Re: [ietf-smtp] DANE / Fwd: ACTION REQUIRED: Renew these Let's Encrypt certificates by March 4
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On Sun, Mar 08, 2020 at 07:42:57AM -0400, Phil Pennock wrote:

> On 2020-03-07 at 04:29 -0500, Viktor Dukhovni wrote:
>
> > Here opinions differ.  Trusting a CA that validates domain control as
> > weakly as Let's Encrypt would not be my choice.  But with half the
> > world trusting Let's Encrypt's "proofs" of domain control, you can
> > perhaps be comfortable in knowing that you're not alone...
> 
> If that's the concern, then tell Let's Encrypt which accounts are
> allowed to issue certificates for your domain.
> 
> Eg, in the zonefile for `spodhuis.org` I have:
> 
> @  CAA  0  issue "globnix.net"
> @  CAA  0  issue "letsencrypt.org\; accounturi=https://acme-v01.api.letsencrypt.org/acme/reg/1134193"

Which then of course relies on their DNSSEC validation working properly,
and (recent case in point) their implementation of CAA records working
properly, ...  I just avoid them entirely:

    dukhovni.org. IN CAA 0 issue dukhovni.org
    _25._tcp.smtp.dukhovni.org. IN TLSA 3 1 1 5e078b3160569f165a69eb860395bbbdc7576c3603c3452b07139c276b26d01c

As I said, opinions differ. :-)

-- 
    Viktor.