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Re: [openpgp] Fingerprints and their collisions resistance

Andrey Jivsov <openpgp@brainhub.org> Thu, 03 January 2013 22:38 UTC

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From: Andrey Jivsov <openpgp@brainhub.org>
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Subject: Re: [openpgp] Fingerprints and their collisions resistance
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On 01/03/2013 11:26 AM, Tony Hansen wrote:
> On 1/3/2013 4:33 AM, Nicholas Cole wrote:
>> One issue with SHA-3 is that the fingerprints are going to be very
>> long.  How should these be displayed to the user?  Hex strings seem
>> unsuitable for this task, and I think any new standard should
>> recommend that fingerprints be displayed in some other way - probably
>> using a different base.
>
> SHA3 is defined for a variety of hash sizes. Using SHA3 does not imply a
> long fingerprint.

I would argue for SHA-3-384 and then possible truncation.

Keccak of different sizes is pretty much implemented as internal 
truncation anyway (of a large sponge structure), plus there is no 
different initialization vectors as for SHA-2 for different hash sizes.

The KeyIDs are the truncation of the fingerprint already.

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