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Re: A block encryption processing idea taken from linear algebra

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Am 17.06.2013 12:13, schrieb JJ:
> On Mon, 17 Jun 2013 09:41:14 +0200, Mok-Kong Shen wrote:
>> Using this as a hint, we propose to do for block encryption processing
>> of n blocks, x1, x2, ... xn, the follwoing, where the f's are
>> invertible non-linear functions, the r's are pseudo-random numbers and
>> the assignments are performed sequentially (the f's and the r's are
>> (secret) key-dependent and different for different rounds, if more
>> then one rounds are used):
>>
>> x1 := f1(x1 + x2 ... + xn + r1)
>> x2 := f2(x1 + x2 ... + xn + r2)
>>      ................
>> xn := fn(x1 + x2 ... + xn + rn)
>
> I'm lost. If n is the number of blocks, then xn is the block number n,
> right?
>
> But this:
> x1 + x2 ... + xn + r1
> suggest to add one block with another then add them with a random number.
>
> How can a block of data be, I assume, arithmetically be added by another
> block and added with a number?
>
> Also... with that information alone, the encryption doesn't seem to be
> decryptable.

If the block size is m bits, then the arithmetics is mod 2**m. If the
f's are invertible, then decryption is evidently without problems,
just like each step of the iterative solution of a system of linear
equations could be reversed (though one of course never does that in
practice).

M. K. Shen

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A block encryption processing idea taken from linear algebra Mok-Kong Shen <mok-kong.shen@t-online.de> - 2013-06-17 09:41 +0200
  Re: A block encryption processing idea taken from linear algebra JJ <duh@nah.meh> - 2013-06-17 17:13 +0700
    Re: A block encryption processing idea taken from linear algebra Mok-Kong Shen <mok-kong.shen@t-online.de> - 2013-06-17 16:01 +0200
      Re: A block encryption processing idea taken from linear algebra JJ <duh@nah.meh> - 2013-06-18 13:03 +0700
        Re: A block encryption processing idea taken from linear algebra Mok-Kong Shen <mok-kong.shen@t-online.de> - 2013-06-18 08:43 +0200
          Re: A block encryption processing idea taken from linear algebra JJ <duh@nah.meh> - 2013-06-18 18:12 +0700
            Re: A block encryption processing idea taken from linear algebra Mok-Kong Shen <mok-kong.shen@t-online.de> - 2013-06-18 15:08 +0200
              Re: A block encryption processing idea taken from linear algebra JJ <duh@nah.meh> - 2013-06-19 15:53 +0700

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