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package Crypt::Random::Source; # git description: v0.13-4-g0edcf44
# ABSTRACT: Get weak or strong random data from pluggable sources
our $VERSION = '0.14';
use strict;
use 5.008;
use warnings;
use Sub::Exporter -setup => {
exports => [qw(
get get_weak get_strong
factory
)],
groups => { default => [qw(get get_weak get_strong)] },
};
use Crypt::Random::Source::Factory;
our ( $factory, $weak, $strong, $any );
# silence some stupid destructor warnings
END { undef $weak; undef $strong; undef $any; undef $factory }
sub factory () { $factory ||= Crypt::Random::Source::Factory->new }
sub _weak () { $weak ||= factory->get_weak }
sub _strong () { $strong ||= factory->get_strong }
sub _any () { $any ||= factory->get }
sub get ($;@) { _any->get(@_) }
sub get_weak ($;@) { _weak->get(@_) }
sub get_strong ($;@) { _strong->get(@_) }
# silence some stupid destructor warnings
END { undef $weak; undef $strong; undef $any; undef $factory }
1;
=pod
=encoding UTF-8
=head1 NAME
Crypt::Random::Source - Get weak or strong random data from pluggable sources
=head1 VERSION
version 0.14
=head1 SYNOPSIS
use Crypt::Random::Source qw(get_strong);
# get 10 cryptographically strong random bytes from an available source
my $bytes = get_strong(10);
=head1 DESCRIPTION
This module provides implementations for a number of byte oriented sources of
random data.
See L<Crypt::Random::Source::Factory> for a more powerful way to locate
sources, and the various sources for specific implementations.
=head1 EXPORTS
=over 4
=item get
=item get_weak
=item get_strong
These functions delegate to a source chosen by an instance of
L<Crypt::Random::Source::Factory>, calling get
=back
=head1 CAVEATS
In versions prior to 0.13, C<rand> could be used as a result of calling
C<get_weak>, or C<get>, if no random device was available. This implies that
not explicitly asking for C<get_strong> on a non POSIX operating system (e.g.
Win32 without the Win32 backend) could have resulted in non cryptographically
random data.
Relatedly, the characterization of C<urandom> as a weak source of randomness is
also largely a misconception, see L<https://www.2uo.de/myths-about-urandom/>
for example.
=head1 SEE ALSO
L<Crypt::Random>, L<Crypt::Util>
=head1 SUPPORT
Bugs may be submitted through L<the RT bug tracker|https://rt.cpan.org/Public/Dist/Display.html?Name=Crypt-Random-Source>
(or L<bug-Crypt-Random-Source@rt.cpan.org|mailto:bug-Crypt-Random-Source@rt.cpan.org>).
=head1 AUTHOR
יובל קוג'מן (Yuval Kogman) <nothingmuch@woobling.org>
=head1 CONTRIBUTORS
=for stopwords Karen Etheridge Florian Ragwitz Graham Knop David Pottage Max Kanat-Alexander Edward Betts
=over 4
=item *
Karen Etheridge <ether@cpan.org>
=item *
Florian Ragwitz <rafl@debian.org>
=item *
Graham Knop <haarg@haarg.org>
=item *
David Pottage <spudsoup@cpan.org>
=item *
Max Kanat-Alexander <mkanat@es-compy.(none)>
=item *
Edward Betts <edward@4angle.com>
=back
=head1 COPYRIGHT AND LICENCE
This software is copyright (c) 2008 by Yuval Kogman.
This is free software; you can redistribute it and/or modify it under
the same terms as the Perl 5 programming language system itself.
=cut
__END__
# ex: set sw=4 et
|
