Subject: [dispatch] Proposed charter for DCRUP

From: "John R Levine" <[email-masked]>
Date: 27 Mar 2017 11:57:20 -0500

The DKIM Crypto Update (DCRUP) working groupkin is chartered to modify 
DKIM to handle more modern cryptographic algorithms and key sizes. DKIM 
(RFC 6376) signatures include a tag that identifies the hash algorithm and 
signing algorithm used in the signature. The only current algorithm is 
RSA, with advice that signing keys should be between 1024 and 2048 bits. 
While 1024 bit signatures are common, longer signatures are not because 
bugs in DNS provisioning software prevent publishing longer keys as DNS 
TXT records.

DCRUP will consider two types of changes to DKIM: additional signing 
algorithms such as those based on elliptic curves, and new public key 
forms, such as putting the public key in the signature and a hash of the 
key in the DNS.  It will limit itself to existing implemented algorithms 
and key forms. Other changes to DKIM, such as new message canonicalization 
schemes, are out of scope.

The WG's output will be an update to DKIM describing the changes to DKIM 
signatures to represent new algorithms or key representations, and to DNS 
TXT records containing public key information.

Milestones:

* Adopt draft for new algorithms and key forms

* WG last call

* Ship it

Regards,
John Levine, [email-masked], Taughannock Networks, Trumansburg NY
Please consider the environment before reading this e-mail. https://jl.ly

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From: Martin Thomson <[email-masked]>
Date: Mon, 27 Mar 2017 12:06:08 -0500

On 27 March 2017 at 11:57, John R Levine <[email-masked]> wrote:
> Ship it

^^

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From: Eric Rescorla <[email-masked]>
Date: Mon, 27 Mar 2017 12:48:12 -0500

LGTM

On Mon, Mar 27, 2017 at 11:57 AM, John R Levine <[email-masked]> wrote:

> signing algorithm used in the signature. The only current algorithm is RSA,
> with advice that signing keys should be between 1024 and 2048 bits. While
> 1024 bit signatures are common, longer signatures are not because bugs in
> DNS provisioning software prevent publishing longer keys as DNS TXT records.
>
> _______________________________________________
> dispatch mailing list
> [email-masked]
> https://www.ietf.org/mailman/listinfo/dispatch
>

---

From: Barry Leiba <[email-masked]>
Date: Mon, 27 Mar 2017 17:46:36 -0500

Ça marche.

Barry

On Mon, Mar 27, 2017 at 11:57 AM, John R Levine <[email-masked]> wrote:
> The DKIM Crypto Update (DCRUP) working groupkin is chartered to modify DKIM
> to handle more modern cryptographic algorithms and key sizes. DKIM (RFC
> 6376) signatures include a tag that identifies the hash algorithm and
> algorithms such as those based on elliptic curves, and new public key forms,
> such as putting the public key in the signature and a hash of the key in the
> DNS.  It will limit itself to existing implemented algorithms and key forms.
> Other changes to DKIM, such as new message canonicalization schemes, are out
> of scope.
>

---

From: Martin J. Dürst <[email-masked]>
Date: Tue, 28 Mar 2017 13:28:18 +0900

Ship it, except for "groupkin" -> "group" in the first line.

(I'm not in Chicago, so I might have missed a process experiment with 
groupkins instead of groups; in this case, please ignore my comment.)

Regards,   Martin.

On 2017/03/28 01:57, John R Levine wrote:
> (RFC 6376) signatures include a tag that identifies the hash algorithm
> and signing algorithm used in the signature. The only current algorithm
> is RSA, with advice that signing keys should be between 1024 and 2048
> bits. While 1024 bit signatures are common, longer signatures are not
> because bugs in DNS provisioning software prevent publishing longer keys
> as DNS TXT records.
>
> and key forms. Other changes to DKIM, such as new message
> canonicalization schemes, are out of scope.
>
> signatures to represent new algorithms or key representations, and to
> DNS TXT records containing public key information.
>
> Milestones:
>
> .

-- 
Prof. Dr.sc. Martin J. Dürst
Department of Intelligent Information Technology
College of Science and Engineering
Aoyama Gakuin University
Fuchinobe 5-1-10, Chuo-ku, Sagamihara
252-5258 Japan

---

From: "John R Levine" <[email-masked]>
Date: 29 Mar 2017 15:55:11 -0500

Here's a draft.  It needs a lot of work but it at least mentions all the 
things I think DCRUP would do.

Name:		draft-levine-dcrup-dkim-crypto
Revision:	00
Title:		Cryptographic Update to DKIM
Document date:	2017-03-29
Group:		Individual Submission
Pages:		5
URL:            https://www.ietf.org/internet-drafts/draft-levine-dcrup-dkim-crypto-00.txt
Status:         https://datatracker.ietf.org/doc/draft-levine-dcrup-dkim-crypto/
Htmlized:       https://tools.ietf.org/html/draft-levine-dcrup-dkim-crypto-00
Htmlized:       https://datatracker.ietf.org/doc/html/draft-levine-dcrup-dkim-crypto-00

----------
On Mon, 27 Mar 2017, John R Levine wrote:

> to handle more modern cryptographic algorithms and key sizes. DKIM (RFC 6376) 
> signatures include a tag that identifies the hash algorithm and signing 
> algorithm used in the signature. The only current algorithm is RSA, with 
> advice that signing keys should be between 1024 and 2048 bits. While 1024 bit 
> signatures are common, longer signatures are not because bugs in DNS 
> provisioning software prevent publishing longer keys as DNS TXT records.
>
> signatures to represent new algorithms or key representations, and to DNS TXT 
> records containing public key information.
>
> Milestones:
>

Regards,

---

From: Jim Fenton <[email-masked]>
Date: Wed, 29 Mar 2017 20:40:52 -0700

Yes, and in addition:

"chartered to modify DKIM" -> "chartered to update DKIM" (unless there's
some specific connotation to "update" in IETF that I'm missing)
"The only current algorithm" -> "The only current signing algorithm"

-Jim

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From: "Murray S. Kucherawy" <[email-masked]>
Date: Thu, 30 Mar 2017 14:00:52 -0500

> TXT records containing public key information.

It would be nice to say that the output will be fully backward-compatible
with the deployed base, but otherwise looks good.

Do we want to say something about discontinuing mandatory support for
512-bit keys in verifiers?

-MSK

---

From: "John R Levine" <[email-masked]>
Date: 30 Mar 2017 14:37:05 -0500

A few minor changes per recent suggestions: modify -> update, allow
deprecation of 512 bit RSA keys, don't be incompatible.

R's,
John

-----------

The DKIM Crypto Update (DCRUP) working groupkin is chartered to update

DCRUP will consider three types of changes to DKIM: additional signing
algorithms such as those based on elliptic curves, changes to key
strength advice and requirements, and new public key forms, such as
putting the public key in the signature and a hash of the key in the
DNS.  It will limit itself to existing implemented algorithms and key
forms. Other changes to DKIM, such as new message canonicalization
schemes, are out of scope.  The WG will as far as possible avoid
changes incompatible with deployed DKIM signers and verifiers.

---

From: Jim Fenton <[email-masked]>
Date: Thu, 30 Mar 2017 12:40:13 -0700

But still "groupkin"?

On 3/30/17 12:37 PM, John R Levine wrote:
> and
> RSA,