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

Mainly to have something pre-defined if SHA-256 is found to be 
vulnerable.  I’m not very concerned about that, if the community is 
responsive in the event that does happen.  I have no qualms about 
dropping it since it gives the draft a single focus.  It’s more for 
potential future-proofing.

Scott

On 2 Jun 2017, at 10:53, Russ Housley wrote:

> Scott:
>
> Since ECDSA P-256 and SHA-256 have the same security strength, what is 
> the reason for adding SHA-512 at this time?  I do not see anything in 
> the Introduction or Security Considerations to answer that question.
>
> Russ
>
>
>
>> On Jun 2, 2017, at 10:46 AM, Rose, Scott <scott.rose@nist.gov> wrote:
>>
>> Updated to reflect WG status.  Also made the following changes:
>>
>> 1. Reduced new algorithms list to just one (ECDSA P=256).
>>
>> 2. Included revised definition of key:value pairs for DKIM keys and 
>> signatures.  One thing I thought about: should the “k=“ in keys 
>> to be mandatory now that RSA isn’t the only algorithm?  Or leave 
>> the default as is, so that anyone using ECDSA must use the “k=“ 
>> tag to signal its use?
>>
>> 3. Just noticed that the format is mess up for the ABNF notation - 
>> dang.  Will fix that.
>>
>> Scott
>>
>> On 2 Jun 2017, at 10:41, 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           : Defining Elliptic Curve Cryptography 
>>> Algorithms for use with DKIM
>>>        Author          : Scott Rose
>>> 	Filename        : draft-ietf-dcrup-dkim-ecc-00.txt
>>> 	Pages           : 7
>>> 	Date            : 2017-06-02
>>>
>>> Abstract:
>>>   DomainKeys Identified Mail (DKIM) uses digital signature to 
>>> associate
>>>   a message with a given sending domain.  Currently, there is only 
>>> one
>>>   cryptography algorithm defined for use with DKIM (RSA).  This
>>>   document defines four new elliptic curve cryptography algorithms 
>>> for
>>>   use with DKIM.  This will allow for algorithm agility if a 
>>> weakness
>>>   is found in RSA, and allows for smaller key length to provide the
>>>   same digital signature strength.
>>>
>>>
>>> The IETF datatracker status page for this draft is:
>>> https://datatracker.ietf.org/doc/draft-ietf-dcrup-dkim-ecc/
>>>
>>> There are also htmlized versions available at:
>>> https://tools.ietf.org/html/draft-ietf-dcrup-dkim-ecc-00
>>> https://datatracker.ietf.org/doc/html/draft-ietf-dcrup-dkim-ecc-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/
>>>
>>> _______________________________________________
>>> Dcrup mailing list
>>> Dcrup@ietf.org
>>> https://www.ietf.org/mailman/listinfo/dcrup
>>
>>
>> ===================================
>> Scott Rose
>> NIST ITL
>> scott.rose@nist.gov
>> +1-301-975-8439
>> GV: +1-571-249-3671
>> ===================================
>>
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>
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===================================
Scott Rose
NIST ITL
scott.rose@nist.gov
+1-301-975-8439
GV: +1-571-249-3671
===================================