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Request #67795 PHP lacks a modern RNG
Submitted: 2014-08-06 08:06 UTC Modified: 2020-04-08 09:11 UTC
Votes:4
Avg. Score:3.8 ± 0.8
Reproduced:0 of 0 (0.0%)
From: ryacko at gmail dot com Assigned:
Status: Suspended Package: Math related
PHP Version: Irrelevant OS:
Private report: No CVE-ID: None
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 [2014-08-06 08:06 UTC] ryacko at gmail dot com 
Description:
------------
Modern RNG are very fast and have better distribution. The Mersenne twister has weak seeds, as well as a small seed state.

Several good pseudo random number generators include:
- http://www.iro.umontreal.ca/~panneton/WELLRNG.html (superior equidistribution)
- ChaCha4 (on some chips it has less than a cycle per byte)
- 128-bit AES counter (on chips with AES instruction, it could very well reach 3 gigabytes per second)
- http://www.math.sci.hiroshima-u.ac.jp/~%20m-mat/MT/SFMT/index.html Mersenne Twister SIMD, 4 times faster

I suggest ChaCha4 or 128-bit AES counter since with either of those one could include stream position in the function.

I suggest the following functions:
b_srand( [, $get_additional_entropy] ) it automatically seeds using an md5 hash of the time. Also includes an option to get additional entropy in the same fashion that session.entropy_length gets entropy.
b_rand( int $min , int $max, [, int $stream_position] )

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 [2014-08-06 09:47 UTC] ryacko at gmail dot com 
Modern RNG are very fast and have better distribution. The Mersenne twister has weak seeds, as well as a small seed state.

Several good pseudo random number generators include:
- http://www.iro.umontreal.ca/~panneton/WELLRNG.html (superior equidistribution)
- ChaCha4 (on some chips it has less than a cycle per byte)
- 128-bit AES counter (on chips with AES instruction, it could very well reach 3 gigabytes per second)
- http://www.math.sci.hiroshima-u.ac.jp/~%20m-mat/MT/SFMT/index.html Mersenne Twister SIMD, 4 times faster

I suggest ChaCha4 or 128-bit AES counter since with either of those one could include stream position in the function.

I suggest the following functions:
b_srand( string $seed [, $get_additional_entropy] ) it automatically seeds using an md5 hash of the time. Also includes an option to get additional entropy in the same fashion that session.entropy_length gets entropy.
b_rand( int $min , int $max, [, int $stream_position] )

An obvious use would be a procedurally generated browser game.
 [2014-08-06 10:03 UTC] ryacko at gmail dot com 
https://www.cisuc.uc.pt/publication/show/2676 Forgot to mention Tyche.
 [2014-08-14 05:23 UTC] levim@php.net
-Status: Open +Status: Verified -Assigned To: +Assigned To: levim
 [2014-08-14 05:23 UTC] levim@php.net 
Ironically, this was fixed long ago but the bug has reoccurred now that we are using Google.
 [2014-08-14 05:23 UTC] levim@php.net
-Status: Verified +Status: Open
 [2014-08-14 05:23 UTC] levim@php.net 
Oops, I somehow responded on the wrong tab. My apologies!
 [2015-02-09 00:24 UTC] levim@php.net
-Assigned To: levim +Assigned To:
 [2016-08-31 19:55 UTC] cmb@php.net
-Type: Bug +Type: Feature/Change Request
 [2020-04-08 09:11 UTC] cmb@php.net
-Status: Open +Status: Suspended
 [2020-04-08 09:11 UTC] cmb@php.net 
This feature request obviously requires discussion regarding the
details.  However, this bug tracker is not suitable for these kind
of discussion, so please bring this request up on the internals
mailing list[1].  For the time being, I'm suspending this ticket.
 
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