hap.random: a new random number library for D

[Joseph Rushton Wakeling via Digitalmars-d-announce]

On Thursday, 12 June 2014 at 08:49:45 UTC, Chris Cain wrote:
> Well, the ultimate conclusion of the conversation with the guy 
> is that:
> 1. ISAAC probably isn't cryptographically secure. Despite not 
> having found any attacks, it just isn't proof of security. It's 
> not been looked at enough to really approve of its usage for 
> that purpose (I'm kind of agreeing with this)
>
> 2. ISAAC in his opinion probably isn't appropriate for non 
> secure uses for much the same reason.
>
> I don't agree with that because everything I've seen for ISAAC 
> shows that it has some really good statistical properties. Even 
> if it's not cryptographically secure, it appears to produce 
> "better" pseudorandom numbers to me than something like MT19937 
> or Well* (and ISAAC is really fast after the initial cost has 
> been paid back)

This comes back to another necessary project -- there needs to be 
a decent suite of tests of randomness for D.  I think in this 
case it's probably best to try and wrap TestU01 etc.

In the circumstances, it sounds like ISAAC would be better placed 
in hap.random.generator than hap.random.crypto, though.

> Ultimately, I think ISAAC (and ISAAC-64) _will_ get more 
> scrutiny in the future as it's a PRNG used in Rust, for 
> instance. I would not suggest it for default purposes, but I 
> think having it as a non-crypto RNG in D wouldn't be a bad idea 
> for those who want to choose to use it.

Yea, this would be great.

> 3. Better ideas for crypto PRNGs are AES-CTR or Salsa20.
>
> I agree with this approach for the crypto section of 
> std.random. I'd also suggest Blum Blum Shub as another thing to 
> add. It's awfully slow, but it's probably one of the few PRNGs 
> that is "provably strong" (that is, it's been reduced to a 
> known hard problem).

Sounds good.

> Also, he suggested me to refer to a presentation he made last 
> year: http://aumasson.jp/data/talks/randomness_hackepfl13.pdf

I'll give this a glance when I get home -- one thing I should 
probably do is collate a reference list for future hap.random 
development.

> I've gone through it and it looks like excellent reference 
> material. Note slide 76 saying: "Don't use RaaS (things like 
> random.org) -> random bits may be shared or reused". Also, it 
> has suggestions for entropy on Windows (CryptGenRandom) which 
> is something that will be necessary as well.

Sounds excellent.  I agree entirely about random.org, although I 
still think we should provide access to it via hap.random.device 
-- we should just surround it with necessary caveats.

> Overall, very enlightening.

Thanks for the research! :-)