Re: Crypto codes #1

From: Edward Cherlin <cherlin_at_pacbell_dot_net>
Date: Sun May 22 2005 - 01:09:06 CDT

On Thursday 19 May 2005 11:36, charlie strauss wrote:
> I'm not sure I understood the entire context of the discussion
> but one thing cuaght my eye:
>
> "2) Each ballot contains (as printed strings or in a barcode):
> > for bv = ballot-id + vote-string:
> > e = encrypt(k, hash(bv))
> > print bv + hash(bv) + e
> >
> > (3) At finalization, k is revealed publicly.
>
> If the hash function is known or knowable does not this reveal
> you ballot and provide a effective receipt? That is to say
> it's going to be fairly trivial, by crypto standards to invert
> the hash of a ballot string I would suspect.

We are using hashes as signatures, not as encryption. The ballot
is already known, and will be published with the hash. This
makes it infeasible to change one ballot and its hash, and keep
the hash for the complete election unchanged.

-- 
Edward Cherlin
Generalist & activist--Linux, languages, literacy and more
"A knot! Oh, do let me help to undo it!"
--Alice in Wonderland
http://cherlin.blogspot.com
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Received on Tue May 31 23:17:44 2005

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