Re: cprng_fast implementation benchmarks

<[email protected]> Thu, 24 Apr 2014 19:23:41 +0000
Newsgroups gmane.os.netbsd.devel.crypto,gmane.os.netbsd.devel.kernel
Message-ID <[email protected]>
On Apr 24, 2014, at 3:03 PM, Mindaugas Rasiukevicius <[email protected]> wrote:

> <[email protected]> wrote:
>> ...
>> Knowing that there are “security issues” with UDP port number generation
>> may mean that a PRNG is inadequate.  Deciding what sort of generator IS
>> adequate, though, means starting with a more definite description of the
>> nature of the attacks that we’re worried about, and the strength of the
>> defense that is desired.
> 
> But you do not disagree with the concept of having weak and strong CPRNG,
> do you?  

I do disagree.  The reason is that I see no requirements that make it possible to decide whether the weak generator is useful.

If it useful only if there are random number consumers that have requirements that a simple PRNG can’t satisfy, and the workload is high enough that the achievable performance of the strong RNG is a concern, and there exists an RNG algorithm that meets both the performance needs and the security needs of those consumers.

There’s a lot of discussion about performance.  And some general statements about security.  But I don’t see the data that allows anyone to decide the question I stated.

In the absence of a “yes” answer, indeed I do disagree with the concept.

	paul