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Re: pycrypto: what am I doing wrong?

References <97dbe3cc-b739-4876-9221-1143dc1b8c73@googlegroups.com> <mailman.1447.1382598445.18130.python-list@python.org> <l4aiai$2l1$1@news.albasani.net>
Date 2013-10-24 18:43 +1100
Subject Re: pycrypto: what am I doing wrong?
From Chris Angelico <rosuav@gmail.com>
Newsgroups comp.lang.python
Message-ID <mailman.1450.1382600610.18130.python-list@python.org> (permalink)

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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

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Thread

pycrypto: what am I doing wrong? Paul Pittlerson <menkomigen6@gmail.com> - 2013-10-23 22:22 -0700
  Re: pycrypto: what am I doing wrong? Chris Angelico <rosuav@gmail.com> - 2013-10-24 18:07 +1100
    Re: pycrypto: what am I doing wrong? Johannes Bauer <dfnsonfsduifb@gmx.de> - 2013-10-24 09:30 +0200
      Re: pycrypto: what am I doing wrong? Chris Angelico <rosuav@gmail.com> - 2013-10-24 18:43 +1100
  Re: pycrypto: what am I doing wrong? Johannes Bauer <dfnsonfsduifb@gmx.de> - 2013-10-24 09:33 +0200
    Re: pycrypto: what am I doing wrong? Johannes Bauer <dfnsonfsduifb@gmx.de> - 2013-10-24 09:35 +0200

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