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Date: Tue, 24 Feb 2015 21:39:41 +0000
Message-ID: <CAPwsocHai8brjoCYRY4Dx8XGCUdDbJwaBNQ_61DcGzSjNqiB9Q@mail.gmail.com>
To: Pierre Joye <pierre.php@gmail.com>
Cc: Anthony Ferrara <ircmaxell@gmail.com>, Sammy Kaye Powers <me@sammyk.me>, 
	PHP internals <internals@lists.php.net>
Content-Type: text/plain; charset=UTF-8
Subject: Re: [PHP-DEV] [RFC] [DISCUSSION] Reliable user-land CSPRNG
From: leight@gmail.com (Leigh)

On 24 February 2015 at 20:54, Pierre Joye <pierre.php@gmail.com> wrote:
> On Feb 24, 2015 12:04 PM, "Anthony Ferrara" <ircmaxell@gmail.com> wrote:
>> PERHAPS, it could be written in such a way that a PECL extension can
>> alter the RNG to accommodate that usecase. But I'd be wary of that and
>> core supporting userland RNGs.
>
> Yes, driver based. That brings some risk but worth exploring this
> possibility.

We can make the function a pointer. That's not a problem. The problem
is when people assign their own function to this pointer :)

> You actually reduce the data set, bytes level or higher, the randomness of
> the data is then restricted or limited and sequences may happen, worst case
> it could make it less hard (or easier) to predict. I have seen these cases
> in a couple of projects which rely heavily on entropy.

If you need very high quality and high throughput entropy I can add
that to this patch. I left it out for now, because I didn't want this
to become over-complicated. If not having an fd-less crypto-quality
high throughput is a show stopper for you then let me know, we can fix
this.