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Date: Thu, 24 Oct 2013 18:43:21 +1100
Subject: Re: pycrypto: what am I doing wrong?
From: Chris Angelico <rosuav@gmail.com>
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On Thu, Oct 24, 2013 at 6:30 PM, Johannes Bauer <dfnsonfsduifb@gmx.de> wrote:
> On 24.10.2013 09:07, Chris Angelico wrote:
>> AES is a stream cipher;
>
> No, it is definitely not! It's a block cipher! However, since he uses
> CFB mode of operation, it behaves like a stream cipher.

Sorry! Quite right. What I meant was, it behaves differently based on
its current state. The SHA256 of "Hello, world!" is 315f5b...edd3 no
matter how many times you calculate it; but the AES-encrypted text is
going to change based on the previously-encrypted text. Hence the need
to either, as stated in your other email, reset the internal state,
or, as stated in my previous one, treat it as a stream.

ChrisA