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Re: An advantage of RSA encryption

From Mok-Kong Shen <mok-kong.shen@t-online.de>
Newsgroups comp.programming
Subject Re: An advantage of RSA encryption
Date 2015-08-01 23:04 +0200
Organization albasani.net
Message-ID <mpjc91$jt2$1@news.albasani.net> (permalink)
References <mpimf8$cc7$1@news.albasani.net> <mpj2fj$361$1@news.albasani.net>

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Am 01.08.2015 um 20:17 schrieb Johannes Bauer:
> On 01.08.2015 16:52, Mok-Kong Shen wrote:
>
>> For a fairly simple and self-sufficient code (employing not
>> probabilistic but provable primes) to perform end-to-end RSA
>> encryption, see http://s13.zetaboards.com/Crypto/topic/7234475/1/
>
> The fact that you rely on Python's random library for generation of
> random numbers for cryptographic purposes reveals that you know
> absolutely nothing about cryptography at all. Since you quote the HAC
> maybe you should try to actually *read* it as well.
>
> Don't try to convince people that you know what you're doing by fancy
> shmancy stuff like provable primes. Instead, maybe focus on not trying
> to make horribly amateurish mistakes like using "import random" for
> cryptographically secure RNG.

PRNs may be directly used as in stream encryption with xoring or
indirectly used. Depending on how indirectly the PRNs are employed,
it could be practically impossible to get from the result of using
the PRNs step by step to the values of the PRNs. Just to indicate
the idea: Suppose an array of
n objects are given and one uses n-1 PRNs to get with Fisher & Yates
a permuted array. (Note that at the base these PRNs are real-valued.)
Now it is practically very hard, I would say barely feasible, to
reconstruct from the two arrays the sequence of n-1 PRNs with sufficient 
accuracy and with that information find the seed of the
PRNG. If one does the permutation a second time and it is required to
reconstrct from the first and last array the PRNs, the task would be
evidently infeasible.

In the Maurer's algorithm there is nowhere a mention that the PRNs
used must be from a CSPRNG. So the requirement is statistically
satisfactory, which Python's PRNG satisfies extremely well.

M. K. Shen

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Thread

An advantage of RSA encryption Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-08-01 16:52 +0200
  Re: An advantage of RSA encryption Johannes Bauer <dfnsonfsduifb@gmx.de> - 2015-08-01 20:17 +0200
    Re: An advantage of RSA encryption Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-08-01 23:04 +0200
      Re: An advantage of RSA encryption Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-08-02 04:32 +0200
      Re: An advantage of RSA encryption Johannes Bauer <dfnsonfsduifb@gmx.de> - 2015-08-02 19:36 +0200
        Re: An advantage of RSA encryption Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-08-02 21:04 +0200
          Re: An advantage of RSA encryption Kaz Kylheku <kaz@kylheku.com> - 2015-08-03 17:31 +0000
            Re: An advantage of RSA encryption Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-08-04 14:44 +0200
              Re: An advantage of RSA encryption Richard Heathfield <rjh@cpax.org.uk> - 2015-08-04 14:01 +0100
                Re: An advantage of RSA encryption Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-08-04 15:07 +0200
                Re: An advantage of RSA encryption Richard Heathfield <rjh@cpax.org.uk> - 2015-08-04 14:21 +0100
                Re: An advantage of RSA encryption Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-08-04 15:24 +0200
                Re: An advantage of RSA encryption Richard Heathfield <rjh@cpax.org.uk> - 2015-08-04 14:43 +0100
                Re: An advantage of RSA encryption Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-08-04 15:49 +0200
                Re: An advantage of RSA encryption Richard Heathfield <rjh@cpax.org.uk> - 2015-08-04 15:56 +0100
                Re: An advantage of RSA encryption Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-08-04 22:05 +0200
                Re: An advantage of RSA encryption Kaz Kylheku <kaz@kylheku.com> - 2015-08-04 15:24 +0000
                Re: An advantage of RSA encryption Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-08-04 22:10 +0200
                Re: An advantage of RSA encryption Richard Heathfield <rjh@cpax.org.uk> - 2015-08-04 21:42 +0100
                Re: An advantage of RSA encryption Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-08-04 23:05 +0200
                Re: An advantage of RSA encryption Richard Heathfield <rjh@cpax.org.uk> - 2015-08-04 22:18 +0100
                Re: An advantage of RSA encryption Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-08-04 23:58 +0200
                Re: An advantage of RSA encryption Chad <cdalten@gmail.com> - 2015-08-04 16:45 -0700
                Re: An advantage of RSA encryption Chad <cdalten@gmail.com> - 2015-08-04 16:55 -0700
                Re: An advantage of RSA encryption Chad <cdalten@gmail.com> - 2015-08-04 22:12 -0700
                Re: An advantage of RSA encryption Richard Heathfield <rjh@cpax.org.uk> - 2015-08-05 07:58 +0100
                Re: An advantage of RSA encryption Chad <cdalten@gmail.com> - 2015-08-05 08:06 -0700
  Re: An advantage of RSA encryption "J. Clarke" <j.clarke.873638@gmail.com> - 2015-08-03 06:50 -0400
    Re: An advantage of RSA encryption Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-08-03 18:28 +0200
      Re: An advantage of RSA encryption "J. Clarke" <j.clarke.873638@gmail.com> - 2015-08-05 22:07 -0400
        Re: An advantage of RSA encryption Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-08-06 11:01 +0200
  Re: An advantage of RSA encryption Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-08-04 15:26 +0200

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