NAME¶
Crypt::URandom - Provide non blocking randomness
VERSION¶
This document describes Crypt::URandom version 0.34
SYNOPSIS¶
use Crypt::URandom();
my $random_string_50_bytes_long = Crypt::URandom::urandom(50);
OR
use Crypt::URandom qw( urandom );
my $random_string_50_bytes_long = urandom(50);
DESCRIPTION¶
This Module is intended to provide an interface to the strongest available
source of non-blocking randomness on the current platform. Platforms currently
supported are anything supporting /dev/urandom and versions of Windows greater
than or equal to Windows 2000.
SUBROUTINES/METHODS¶
- "urandom"
- This function accepts an integer and returns a string of the same size
filled with random data. The first call will initialize the native
cryptographic libraries (if necessary) and load all the required Perl
libraries
DIAGNOSTICS¶
- "No secure alternative for random number generation for Win32
versions older than W2K"
- The module cannot run on versions of Windows earlier than Windows 2000 as
there is no cryptographic functions provided by the operating system.
- "Could not import CryptAcquireContext"
- The module was unable to load the CryptAcquireContextA function from the
advapi32 dynamic library. The advapi32 library cannot probably be
loaded.
- "CryptAcquireContext failed"
- The module was unable to call the CryptAcquireContextA function from the
advapi32 dynamic library.
- "Could not import CryptGenRandom"
- The module was unable to load the CryptGenRandom function from the
advapi32 dynamic library.
- "Could not import SystemFunction036"
- The module was unable to load the SystemFunction036 function from the
advapi32 dynamic library.
- "The length argument must be supplied and must be an
integer"
- The get method must be called with an integer argument to describe how
many random bytes are required.
- "CryptGenRandom failed"
- The Windows 2000 CryptGenRandom method call failed to generate the
required amount of randomness
- "RtlGenRand failed"
- The post Windows 2000 RtlGenRand method call failed to generate the
required amount of randomness
- "Only read n bytes from path"
- The /dev/urandom device did not return the desired amount of random
bytes
- "Failed to read from path"
- The /dev/urandom device returned an error when being read from
- "Failed to open path"
- The /dev/urandom device returned an error when being opened
CONFIGURATION AND ENVIRONMENT¶
Crypt::URandom requires no configuration files or environment variables.
DEPENDENCIES¶
If the platform is Win32, the Win32::API module will be
required. Otherwise no other modules other than those provided by perl will be
required
INCOMPATIBILITIES¶
None reported.
BUGS AND LIMITATIONS¶
No bugs have been reported.
Please report any bugs or feature requests to
"bug-crypt-urandom@rt.cpan.org", or through the web interface at
<
http://rt.cpan.org>.
AUTHOR¶
David Dick "<ddick@cpan.org>"
ACKNOWLEDGEMENTS¶
The Win32::API code for interacting with Microsoft's CryptoAPI was stolen with
extreme gratitude from Crypt::Random::Source::Strong::Win32 by Max
Kanat-Alexander
LICENSE AND COPYRIGHT¶
Copyright (c) 2011, David Dick "<ddick@cpan.org>". All rights
reserved.
This module is free software; you can redistribute it and/or modify it under the
same terms as Perl itself.
DISCLAIMER OF WARRANTY¶
BECAUSE THIS SOFTWARE IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY FOR THE
SOFTWARE, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN OTHERWISE
STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE
SOFTWARE "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR
IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO
THE QUALITY AND PERFORMANCE OF THE SOFTWARE IS WITH YOU. SHOULD THE SOFTWARE
PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR, OR
CORRECTION.
IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL ANY
COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR REDISTRIBUTE THE
SOFTWARE AS PERMITTED BY THE ABOVE LICENCE, BE LIABLE TO YOU FOR DAMAGES,
INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING
OUT OF THE USE OR INABILITY TO USE THE SOFTWARE (INCLUDING BUT NOT LIMITED TO
LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR
THIRD PARTIES OR A FAILURE OF THE SOFTWARE TO OPERATE WITH ANY OTHER
SOFTWARE), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE
POSSIBILITY OF SUCH DAMAGES.