NAME
Data::Pwgen - simple password generation and assessment
SYNOPSIS
use Data::Pwgen qw(pwgen pwstrength);
my $pass = pwgen(12);
my $str = pwstrength($pass);
DESCRIPTION
This is a simple module that implements generation and assesment of
secure passwords.
FUNCTIONS
pwgen($length, $charclass)
Generate a password with the (optional) given length and (also optional)
given character class. The default length is 16. If specified, the
character class must be one of the following:
lower
Lower-case letters.
upper
Upper-case letters.
chars
Lower- and upper-case letters.
nums
The digits 0 through 9.
signs
The following characters: % $ _ - + * & / = ! #
alphanum
Lower- and upper-case letters and digits.
alphasym
*alphanum* plus *signs*.
If you pass anything other than one of the above, it will fall back to
the default, which is *alphanum*.
pwstrength
Returns a numeric rating of the quality of the supplied (password)
string.
strength
An alias for pwstrength(), retained for backwards compatibility. At some
point this alias will go away.
SEE ALSO
The following modules provide similar capabilities: App::Genpass,
Crypt::GeneratePassword, String::Random, Data::Random, String::MkPasswd.
<http://neilb.org/reviews/passwords.html>: a review of CPAN modules for
generating passwords.
REASONING
There are many modules for generating random strings or passwords.
This section explains my reason for writing this module and why you
wouldn't want to use it in some cases.
WHY USE THIS MODULE?
Use this module if you need code which is easy to comprehend and review.
Use this module if you do not have strict constraints on cryptographic
security and you don't need passwords/strings which are easy to
remember.
These strings are made to be used by machines, not for humans.
This module is rather fast. It doesn't use fancy tricks to cut the time,
but the approach used for generating the passwords is simple and thus
this module won't block for a long time.
The runtime complexity is about O(n*m) where n is the length of the
chosen character class and m is the requested length of the password.
WHY NOT USE THIS MODULE?
If you need either pronounceable password or have high requirements for
the cryptographic properties of the generated strings you should not use
this module. In this case please have a look at those listed above or
Neils' great review.
WHY WAS THIS MODULE WRITTEN?
When looking for suiteable modules on CPAN I found that those present
were either unmaintained, had a very bad worst-case runtime or were
completely unreadable.
Please not that this code was written some time ago for use in VBoxAdm
<http://www.vboxadm.net/> some time ago, but refactored and released on
its own just now.
AUTHOR
Dominik Schulz <dominik.schulz@gauner.org>
COPYRIGHT AND LICENSE
This software is copyright (c) 2012 by Dominik Schulz.
This is free software; you can redistribute it and/or modify it under
the same terms as the Perl 5 programming language system itself.