Re: [Dcrup] Hashed Key Records

Phillip Hallam-Baker <phill@hallambaker.com> Fri, 23 June 2017 00:01 UTC

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From: Phillip Hallam-Baker <phill@hallambaker.com>
Date: Thu, 22 Jun 2017 20:01:28 -0400
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To: Steve Atkins <steve@blighty.com>
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Subject: Re: [Dcrup] Hashed Key Records
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On Thu, Jun 22, 2017 at 7:51 PM, Steve Atkins <steve@blighty.com> wrote:

>
> (and maybe be specific about what embedded whitespace means)
>
> These all seem good features..
>
> I'm reminded of the $1$... style password hashes. Immediately recognizable
> in
> general, but including enough embedded information that you know which
> spec to follow.
>

​The other thing I would like is the ability to truncate fingerprints to
arbitrary lengths by truncating the string specifying the fingerprint. In
all but a few applications, a fingerprint with a workfactor of 2^118 is
sufficient to prevent most attacks.​ That is 25 characters in my proposal
(since there is a one byte algorithm identifier prefix).

There are also some hacks that can be used for compressing the fingerprint
but I don't think these would be relevant here.