Re: [DNSOP] I-D Action: draft-ietf-dnsop-glue-is-not-optional-02.txt

John R Levine <> Wed, 28 July 2021 21:30 UTC

Return-Path: <>
Received: from localhost (localhost []) by (Postfix) with ESMTP id 27FA93A15DC for <>; Wed, 28 Jul 2021 14:30:02 -0700 (PDT)
X-Virus-Scanned: amavisd-new at
X-Spam-Flag: NO
X-Spam-Score: -2.099
X-Spam-Status: No, score=-2.099 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_BLOCKED=0.001, SPF_PASS=-0.001, URIBL_BLOCKED=0.001] autolearn=ham autolearn_force=no
Authentication-Results: (amavisd-new); dkim=pass (2048-bit key) header.b=mc/mkr8x; dkim=pass (2048-bit key) header.b=XVw5ebrC
Received: from ([]) by localhost ( []) (amavisd-new, port 10024) with ESMTP id KkvYFI42MW4m for <>; Wed, 28 Jul 2021 14:29:56 -0700 (PDT)
Received: from ( [IPv6:2001:470:1f07:1126:0:43:6f73:7461]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by (Postfix) with ESMTPS id 5B2623A2191 for <>; Wed, 28 Jul 2021 14:29:50 -0700 (PDT)
Received: (qmail 85897 invoked from network); 28 Jul 2021 21:29:48 -0000
DKIM-Signature: v=1; a=rsa-sha256; c=simple;; h=date:message-id:from:to:cc:subject:in-reply-to:references:mime-version:content-type; s=14f87.6101cc4c.k2107; bh=BmixyHS3+ghicLjYar/gNehS7jGA9aIq/KbBk5iqFQ4=; b=mc/mkr8xPP3og/fduuNQ/KHkzHr71XAb0G30KW7r1yTNHEksrKYyT5nRIc84me70QxjpwkNPCUNtYEcPWJVHx3+NlfyKaThTOK92h9wJSYkpU+ygo34QzzxgkyIc5gnEFN3zoIJeRxKiXBmh4i5YrUZhmPaUXQvQwxLkSOZuAo53qFNguQKItr9bhSgsPw0xEwTvN4C58krazBp9qgSkrzstIfCo1OXAaT/x/SND+ltWflztP9xpZ4wz1oTyzOgCN+cI1m5nQCIjLilJ3nUqT8WXmmv/xGzWHxh5MsCIDBwrKMHG7cZCwk6o7TjcVL1C5fR8iLs5p1is6irgaU3Uaw==
DKIM-Signature: v=1; a=rsa-sha256; c=simple;; h=date:message-id:from:to:cc:subject:in-reply-to:references:mime-version:content-type; s=14f87.6101cc4c.k2107; bh=BmixyHS3+ghicLjYar/gNehS7jGA9aIq/KbBk5iqFQ4=; b=XVw5ebrCSP2NfsucHowq0Jc7kODEX/BpkBGAtoRAEcrx8RsE9UUy7nElCJ+NFdeqJ62YSLHgxB50h65bqy6VzFvYJPR7gKxZ2MmH13AwXqXfL9okKGbO2obHK3Ech0DtqaXCF4dVtukaboQC3ZZGYDFWZaKwYuBMkHc+tNGA/4325u/TjNPPgv3yseC7TPTTro1QnP3aDr0yJc/Z+Wlwn/fphkET8589frjsnXk2G7p4KpdxJMj0gajoNBGQAIHoPx6Z1K3XEOJmkkkL6l1GhKJFuOcBh24HC9yQUvGiCcyDOhxysPuTgWgg0golnbIdChX+T9x346a+yi3v5Cj16A==
Received: from ary.qy ([IPv6:2001:470:1f07:1126::78:696d:6170]) by ([IPv6:2001:470:1f07:1126::78:696d:6170]) with ESMTPS (TLS1.2 ECDHE-RSA AES-256-GCM AEAD) via TCP6; 28 Jul 2021 21:29:47 -0000
Received: by ary.qy (Postfix, from userid 501) id 0838D2542D0D; Wed, 28 Jul 2021 17:29:46 -0400 (EDT)
Received: from localhost (localhost []) by ary.qy (Postfix) with ESMTP id 677272542CEF; Wed, 28 Jul 2021 17:29:46 -0400 (EDT)
Date: Wed, 28 Jul 2021 17:29:46 -0400
Message-ID: <>
From: John R Levine <>
To: Shumon Huque <>
Cc: " WG" <>
X-X-Sender: johnl@ary.qy
In-Reply-To: <>
References: <> <20210727201504.2939B25365A4@ary.qy> <> <> <> <> <>
MIME-Version: 1.0
Content-Type: text/plain; charset="US-ASCII"; format="flowed"
Archived-At: <>
Subject: Re: [DNSOP] I-D Action: draft-ietf-dnsop-glue-is-not-optional-02.txt
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: IETF DNSOP WG mailing list <>
List-Unsubscribe: <>, <>
List-Archive: <>
List-Post: <>
List-Help: <>
List-Subscribe: <>, <>
X-List-Received-Date: Wed, 28 Jul 2021 21:30:02 -0000

We are clearly talking past each other here.  Let's see what the rest of 
the WG thinks.

I think we need to think harder about "what is required for the DNS 
protocol to work" vs "what do I think might be a nice idea."


On Wed, 28 Jul 2021, Shumon Huque wrote:

> On Wed, Jul 28, 2021 at 12:20 PM John R Levine <> wrote:
>> On Wed, 28 Jul 2021, Shumon Huque wrote:
>>> Sibling glue was already covered in RFC 1034 (even though there was no
>> term
>>> for it). ...
>> Sure, but we've been cleaning up the ambiguities and errors in 1034 for 30
>> years.  A straightforward reading of that paragraph also gives you the
>> Kaminsky attack.
> The Kaminsky attack can redirect in-bailiwick nameserver names just as
> easily as out-of-bailiwick. The defenses against it are (1) make it harder
> (source port randomization etc), or (2) deploy DNSSEC. Glue is
> unauthenticated
> anyway, so the only real defense against misdirection is DNSSEC and
> a secure referral to the child.
> Also, sibling glue is easier to accept for a paranoid resolver. It may not
> be in-bailiwick (i.e. a subdomain) of the "delegated zone", but it is in-
> bailiwick of the "delegating zone". If a paranoid resolver, ignores and
> re-queries for the sibling names, it ends up requerying the same authority
> and then getting a response with in-bailiwick glue. So, it just did a bunch
> of additional work for not much benefit in my opinion.
> But this is an interesting topic. What do resolver implementations do
> when presented with sibling glue? Can implementers comment? I think
> this can help inform what we recommend in the draft.
> "MUST" in RFC-ese means you have to do something in order to interoperate.
>> I think we all agree that the DNS will operate fine without sibling glue,
>> other than NS loops which I personally don't care about. That makes it at
>> most a MAY, and I agree with Geoff's reasons to take it out completely.
> I don't agree we should take it out, since as I pointed out, RFC 1034
> explicitly
> covers this type of glue (without giving it a name), and the algorithm will
> include it if it is there. If there is a compelling security or other
> reason to
> remove that, someone should make that case (I haven't heard it yet).
> But it seems we will not get consensus on truncating if sibling glue doesn't
> fit, so I'm okay with relaxing that requirement.
> Shumon.

John Levine,, Taughannock Networks, Trumansburg NY
Please consider the environment before reading this e-mail.