Re: [openpgp] SHA3 algorithm ids.

Phillip Hallam-Baker <phill@hallambaker.com> Sat, 08 August 2015 22:35 UTC

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Date: Sat, 8 Aug 2015 18:35:25 -0400
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From: Phillip Hallam-Baker <phill@hallambaker.com>
To: ianG <iang@iang.org>
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Subject: Re: [openpgp] SHA3 algorithm ids.
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On Sat, Aug 8, 2015 at 6:26 PM, ianG <iang@iang.org>; wrote:

> On 8/08/2015 13:43 pm, Paul Wouters wrote:
>
>> What is the rationale to implement all sha3 variants?
>>
>
> I agree, I'd like to see a really good rationale.
>
> I understand some protocols need lower grade versions for performance
>> reasons but that seems to matter a lot less for openpgp usage. Why not just
>> implement sha3-512?
>>
>
> One would be good.  Suits me to go for the longest one.
>
> How about this:
>
>
>
>       ID           Algorithm                             Text Name
>>>       --           ---------                             ---------
>>>
>>
> snip
>
>       12         - RESERVED
>>>       13         - RESERVED
>>>       14         - RESERVED
>>>       15         - SHA3-512 [FIPS202]                    "SHA3-512"
>>>
>>
>
>
> And while we're at it, can we add DEPRECATED to all the rest except
> SHA(2)512 ?


Discussion in CFRG was definitely pointing to using 512 for the hash
required for the internal bit. So if we choose one it should be 512 and
truncate where necessary in the UI part.