Re: [openpgp] New fingerprint: which hash algo

Alessandro Barenghi <alessandro.barenghi.polimi@gmail.com> Fri, 09 October 2015 16:47 UTC

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From: Alessandro Barenghi <alessandro.barenghi.polimi@gmail.com>
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Subject: Re: [openpgp] New fingerprint: which hash algo
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On 10/08/2015 10:48 PM, ianG wrote:

> 2.  The reason SHA-256 is the most popular these days is that, in the
> wake of the 2004 Shandong hashquake, we've made a stunning amount of
> progress in upgrading.  We've almost decided against SHA1 in
> certificates.  We're almost serious about it.  And now that freestart
> collisions are chewing it down to its last 4 bits, 

Actually, they finished chewing
https://sites.google.com/site/itstheshappening/

(still only a freestart collision, but full 80 rounds)

> we might actually ... do it.

Yep, and IMHO picking a hash function with a different inner structure
from SHA-1, and designed to address the issue coming with it, such as
SHA-3 may quite be a good idea.
After all, ~89% of the signatures currently present on the sks keyserver
network are made over a SHA-1 hash, and it may take a while to update
them all.

Cheers

Alessandro