Re: Encrypting an External HDD

[Celejar <celejar@gmail.com>]

On Fri, 17 Apr 2015 14:25:36 -0700
David Christensen <dpchrist@holgerdanske.com> wrote:

> On 04/17/2015 12:41 PM, Reco wrote:

...

> > [Perl's Math::Random::ISAAC::XS] doesn't seem to use kernel-based entropy at all. Thank
> > you for pointing me out at it, now I know it so I avoid it.
> 
> ISAAC is very useful when I want a repeatable stream of random numbers, 
> such as for testing.
> 
> 
> ISAAC can generate cryptographically secure random number streams by 
> feeding it a "good" random seed:
> 
> 2015-04-17 14:22:23 dpchrist@t2250 ~
> $ time dd if=/dev/random bs=16 count=1 2>/dev/null | perl 
> -MMath::Random::ISAAC::XS -e 
> '$r=Math::Random::ISAAC::XS->new(@ARGV);while(print $r->irand){}' | dd 
> iflag=fullblock of=/dev/null bs=1M count=100 2>/dev/null
> 
> real	0m18.350s
> user	0m18.305s
> sys	0m0.256s

Yes, this is what Math::Random::Secure does - it seeds
Math::Random::ISAAC from /dev/urandom:

http://search.cpan.org/~mkanat/Math-Random-Secure-0.06/lib/Math/Random/Secure.pm#IMPLEMENTATION_DETAILS

Celejar