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RE: Encryption padding

From: Christian Geuer-Pollmann <geuer-pollmann@nue.et-inf.uni-siegen.de>
Date: Mon, 13 Nov 2000 20:40:40 +0100
To: "Smith, Ned" <ned.smith@intel.com>, xml-encryption@w3.org
Message-ID: <3485432031.974148040@clouseau>
Dear Ned,

--On Montag, 13. November 2000 10:46 -0800 "Smith, Ned" 
<ned.smith@intel.com> wrote:

> One approach could be to hash the contents and return the encrypted
> hash value. It will always be the same size. Since the possible
> choices are few, the recipient can easily compare hash values from
> the set of possible answers.

But this is an application specific scenario only interesting if you have a 
set of possible (allowed) element contents:

plaintext:

<presidential_vote>Al Gore</presidential_vote>
<presidential_vote>George Bush</presidential_vote>

hashed plaintext:

<presidential_vote>a658e41268d4ce600b35476f639b93e9</presidential_vote>
<presidential_vote>48a80bbd36f550e2b9ab2fb4e698007f</presidential_vote>

encrypted hashes:

<presidential_vote>ai4uWugBlVTc/r1KvLHVG0zT/0d/64h3kTGhuusR9gi5qTMZkoRQlQ==
</presidential_vote>
<presidential_vote>AD1ywrLLzc2Y3sIlkpJ9HglYSdB9TEZ0VmxSbYboG5GHfLRkaj4RSQ==
</presidential_vote>

But how do you want to come from the hashed form back to plaintext?




Christian Geuer-Pollmann

web:  <http://www.nue.et-inf.uni-siegen.de/~geuer-pollmann/>
Received on Monday, 13 November 2000 14:52:11 GMT

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