Re: [Dcrup] I-D Action: draft-ietf-dcrup-dkim-usage-00.txt

I’ve read the draft and I admire the willingness to plant a stake in 
the ground in making rsa-sha1 obsolete.

I think it would help to be more explicit about which requirement 
applies to which role (implement vs deploy/administrate).  For example:

3 DKIM Signing and Verification Algorithms

    This section replaces [RFC6376] Section 3.3 in its entirety.

    DKIM supports multiple digital signature algorithms.  Two algorithms
    were defined by [RFC6376]: rsa-sha1 and rsa-sha256.  Signers MUST
    implement and sign using rsa-sha256.  Verifiers MUST implement rsa-
    sha256 and MAY implement rsa-sha1 for backwards compatibility.
    The rsa-sha1 signing algorithm is obsolete and MUST NOT be
    used.

3.1.  The rsa-sha1 Signing Algorithm

    This algorithm is obsolete and MUST NOT be used by signers.

This doesn’t change the main idea, but calls out the fact that 
rsa-sha1 will be sticking around for a period of time as administrators 
are not going to read this doc and/or not going to change things that 
are working for them now.

Scott

On 30 May 2017, at 20:58, internet-drafts@ietf.org wrote:

> A New Internet-Draft is available from the on-line Internet-Drafts 
> directories.
> This draft is a work item of the DKIM Crypto Update of the IETF.
>
>         Title           : Cryptographic Algorithm and Key Usage to 
> DKIM
>         Author          : Scott Kitterman
> 	Filename        : draft-ietf-dcrup-dkim-usage-00.txt
> 	Pages           : 5
> 	Date            : 2017-05-30
>
> Abstract:
>    The cryptographic algorithm and key size requirements included when
>    DKIM was designed in the last decade are functionally obsolete and 
> in
>    need of immediate revision.  This document updates DKIM 
> requirements
>    to those minimaly suitable for operation with currently specified
>    algorithms.  This document updates RFC 6376.
>
>
> The IETF datatracker status page for this draft is:
> https://datatracker.ietf.org/doc/draft-ietf-dcrup-dkim-usage/
>
> There are also htmlized versions available at:
> https://tools.ietf.org/html/draft-ietf-dcrup-dkim-usage-00
> https://datatracker.ietf.org/doc/html/draft-ietf-dcrup-dkim-usage-00
>
>
> Please note that it may take a couple of minutes from the time of 
> submission
> until the htmlized version and diff are available at tools.ietf.org.
>
> Internet-Drafts are also available by anonymous FTP at:
> ftp://ftp.ietf.org/internet-drafts/
>
> _______________________________________________
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> Dcrup@ietf.org
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===================================
Scott Rose
NIST ITL
scott.rose@nist.gov
+1-301-975-8439
GV: +1-571-249-3671
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