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Re: [Cfrg] Summary of the poll: Elliptic Curves - signature scheme: friendliness to low memory implementations (ends on June 3rd)

Paul Hoffman <paul.hoffman@vpnc.org> Fri, 19 June 2015 21:56 UTC

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From: Paul Hoffman <paul.hoffman@vpnc.org>
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References: <557FEA01.7070207@isode.com> <557FE6E4.3040509@isode.com> <20150619062752.3506.qmail@cr.yp.to> <CAA4PzX3Toc+Ev6rp38rU73rinygxGPE7_FLXOWrRMh+N4SPyYQ@mail.gmail.com> <CAMfhd9Ua=fV_MKMfj1T8dApM6fA7Ko4y8-_uu03dd_WpmK4VvQ@mail.gmail.com>
To: Adam Langley <agl@imperialviolet.org>
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Subject: Re: [Cfrg] Summary of the poll: Elliptic Curves - signature scheme: friendliness to low memory implementations (ends on June 3rd)
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On Jun 19, 2015, at 2:32 PM, Adam Langley <agl@imperialviolet.org> wrote:
> So, offline, I iterate over many domain
> names and pick one where the hash of the certificate structure for
> that name and my public-key looks like a valid CRL message.

In order to do this, don't you need to have broken the preimage resistance of the hash, or that the output length of the hash has to be 160 bits or less?

--Paul Hoffman

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