Initializing Secure Random (Reprise)

[Peter Levart]

On 11/24/2014 09:46 PM, roger riggs wrote:
> Hi,
>
> This topic has languished for a bit and could use a bit of expertise from
> Windows developers.
>
> The improvements in entropy for initializing Secure Random in JDK 8 have
> some negative attributes that affect maintainability, robustness and 
> performance[1].
> The dependency on networking, can in some OS's and configurations lead
> to increased startup times and issues with bootstrapping the Java 
> runtime.
>
> Martin has proposed[2] an alternative for Linux based on /dev/urandom
> with a fallback to a simpler algorithm if /dev/urandom is not available.
>
> Since /dev/urandom is not native to Windows, it seems prudent to identify
> a corresponding source of entropy data.
>
> What are the recommended ways on Windows to get seeds for random?
> Please suggest one or more ways to initialize SecureRandom

Hi Roger,

Do you mean SecureRandom or ThreadLocalRandom/SplittbleRandom, since the 
8060435 talks about the later two ?

As Bernd identified, the Windows equivalent to /dev/urandom is MSCAPI.

5 months ago I made an attempt to expose a part of contained internal 
java security API to get access to /dev/urandom based and MSCAPI based 
seed generators. Here's the thread with the discussion:

http://mail.openjdk.java.net/pipermail/core-libs-dev/2014-June/027256.html

The minimal patch was the following:

http://cr.openjdk.java.net/~plevart/jdk9-dev/TLR_SR_SeedGenerator/webrev.01/

Regards, Peter

>
> Thanks, Roger
>
> p.s. Sorry to be covering old ground but I don't have all the context.
>
>
> [1] 8060435  SecureRandom initialization latency on Windows
>      https://bugs.openjdk.java.net/browse/JDK-8060435
>
> [2] 
> http://cr.openjdk.java.net/~martin/webrevs/openjdk9/ThreadLocalRandom-system-entropy/