Re: [secdir] secdir review of draft-moonesamy-sshfp-ed25519-01

Stephen Farrell <stephen@tolerantnetworks.com> Fri, 30 May 2014 22:42 UTC

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Date: Fri, 30 May 2014 23:42:31 +0100
From: Stephen Farrell <stephen@tolerantnetworks.com>
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To: S Moonesamy <sm+ietf@elandsys.com>, "Joseph Salowey (jsalowey)" <jsalowey@cisco.com>
References: <2ACBFFE4-BCEB-4F6D-A2D3-861BADF543DE@cisco.com> <6.2.5.6.2.20140530040300.0bb93070@elandnews.com> <D1342262-144C-4939-B005-5E042CAF7394@cisco.com> <20140530141618.kgnw4u9b4gw80o4s@webmail.mit.edu> <6.2.5.6.2.20140530114625.0c0d1aa8@elandnews.com> <868A3427-6B46-4110-8D4B-45857D260C1D@cisco.com> <6.2.5.6.2.20140530135131.0c7bdba0@elandnews.com>
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Cc: iesg@ietf.org, secdir@ietf.org, ietf@ietf.org, draft-moonesamy-sshfp-ed25519.all@tools.ietf.org
Subject: Re: [secdir] secdir review of draft-moonesamy-sshfp-ed25519-01
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On 30/05/14 23:22, S Moonesamy wrote:
> Hi Joe,
> At 13:42 30-05-2014, Joseph Salowey (jsalowey) wrote:
>> [Joe] My concern is that there is not enough information in the draft
>> to know what goes into the hash that is the subject of the code point
>> assignment.  Perhaps it is obvious to someone who implemented the SSH
>> code that is not documented in this draft, but it is not obvious to me
>> as a reader of the draft.
> 
> That's a fair point.  I propose adding the following text in Section 2
> as a warning to the reader:
> 
>   The format of the ED25519 public key with SHA-256 fingerprint is
>   not documented in an authoritative specification.

Why? Why not just look at the code and write down what that does
in terms of formatting the input.

If >1 implementation interoperates it can't be that hard.

S.

> 
> Regards,
> S. Moonesamy