NAME
Digest::Bcrypt - Perl interface to the bcrypt digest algorithm
SYNOPSIS
#!/usr/bin/env perl
use strict;
use warnings;
use utf8;
use Digest; # via the Digest module (recommended)
my $bcrypt = Digest->new('Bcrypt', cost => 12, salt => 'abcdefgh♥stuff');
# You can forego the cost and salt in favor of settings strings:
my $bcrypt = Digest->new('Bcrypt', settings => '$2a$20$GA.eY03tb02ea0DqbA.eG.');
# $cost is an integer between 1 and 31
$bcrypt->cost(12);
# $salt must be exactly 16 octets long
$bcrypt->salt('abcdefgh♥stuff');
# OR, for good, random salts:
use Data::Entropy::Algorithms qw(rand_bits);
$bcrypt->salt(rand_bits(16*8)); # 16 octets
# You can forego the cost and salt in favor of settings strings:
$bcrypt->settings('$2a$20$GA.eY03tb02ea0DqbA.eG.');
# add some strings we want to make a secret of
$bcrypt->add('some stuff', 'here and', 'here');
my $digest = $bcrypt->digest;
$digest = $bcrypt->hexdigest;
$digest = $bcrypt->b64digest;
# bcrypt's own non-standard base64 dictionary
$digest = $bcrypt->bcrypt_b64digest;
# Now, let's create a password hash and check it later:
use Data::Entropy::Algorithms qw(rand_bits);
my $bcrypt = Digest->new('Bcrypt', cost=>20, salt=>rand_bits(16*8));
my $settings = $bcrypt->settings(); # save for later checks.
my $pass_hash = $bcrypt->add('Some secret password')->digest;
# much later, we can check a password against our hash via:
my $bcrypt = Digest->new('Bcrypt', settings=>$settings);
if ($bcrypt->add($value_from_user)->digest eq $known_pass_hash) {
say "Your password matched";
}
else {
say "Try again!";
}
NOTICE
While maintenance for Digest::Bcrypt will continue, there's no reason
to use Digest::Bcrypt when Crypt::Eksblowfish::Bcrypt already exists.
We suggest that you use Crypt::Eksblowfish::Bcrypt instead.
DESCRIPTION
Digest::Bcrypt provides a Digest-based interface to the
Crypt::Eksblowfish::Bcrypt library.
Please note that you must set a salt of exactly 16 octets in length,
and you must provide a cost in the range 1..31.
ATTRIBUTES
Digest::Bcrypt implements the following attributes.
cost
$bcrypt = $bcrypt->cost(20); # allows for method chaining
my $cost = $bcrypt->cost();
An integer in the range 1..31, this is required.
See Crypt::Eksblowfish::Bcrypt for a detailed description of cost in
the context of the bcrypt algorithm.
When called with no arguments, it will return the current cost.
salt
$bcrypt = $bcrypt->salt('abcdefgh♥stuff'); # allows for method chaining
my $salt = $bcrypt->salt();
# OR, for good, random salts:
use Data::Entropy::Algorithms qw(rand_bits);
$bcrypt->salt(rand_bits(16*8)); # 16 octets
Sets the value to be used as a salt. Bcrypt requires exactly 16 octets
of salt.
It is recommenced that you use a module like Data::Entropy::Algorithms
to provide a truly randomized salt.
When called with no arguments, it will return the current salt.
settings
$bcrypt = $bcrypt->settings('$2a$20$GA.eY03tb02ea0DqbA.eG.'); # allows for method chaining
my $settings = $bcrypt->settings();
A settings string can be used to set the "salt" in Digest::Bcrypt and
"cost" in Digest::Bcrypt automatically. Setting the settings will
override any current values in your cost and salt attributes.
For details on the settings string requirements, please see
Crypt::Eksblowfish::Bcrypt.
When called with no arguments, it will return the current settings
string.
METHODS
Digest::Bcrypt inherits all methods from Digest::base and
implements/overrides the following methods as well.
new
my $bcrypt = Digest->new('Bcrypt', %params);
my $bcrypt = Digest::Bcrypt->new(%params);
my $bcrypt = Digest->new('Bcrypt', \%params);
my $bcrypt = Digest::Bcrypt->new(\%params);
Creates a new Digest::Bcrypt object. It is recommended that you use the
Digest module in the first example rather than using Digest::Bcrypt
directly.
Any of the "ATTRIBUTES" in Digest::Bcrypt above can be passed in as a
parameter.
add
$bcrypt->add("a"); $bcrypt->add("b"); $bcrypt->add("c");
$bcrypt->add("a")->add("b")->add("c");
$bcrypt->add("a", "b", "c");
$bcrypt->add("abc");
Adds data to the message we are calculating the digest for. All the
above examples have the same effect.
b64digest
my $digest = $bcrypt->b64digest;
Same as "digest", but will return the digest base64 encoded.
The length of the returned string will be 31 and will only contain
characters from the ranges '0'..'9', 'A'..'Z', 'a'..'z', '+', and '/'
The base64 encoded string returned is not padded to be a multiple of 4
bytes long.
bcrypt_b64digest
my $digest = $bcrypt->bcrypt_b64digest;
Same as "digest", but will return the digest base64 encoded using the
alphabet that is commonly used with bcrypt.
The length of the returned string will be 31 and will only contain
characters from the ranges '0'..'9', 'A'..'Z', 'a'..'z', '+', and '.'
The base64 encoded string returned is not padded to be a multiple of 4
bytes long.
Note: This is bcrypt's own non-standard base64 alphabet, It is not
compatible with the standard MIME base64 encoding.
clone
my $clone = $bcrypt->clone;
Creates a clone of the Digest::Bcrypt object, and returns it.
digest
my $digest = $bcrypt->digest;
Returns the binary digest for the message. The returned string will be
23 bytes long.
hexdigest
my $digest = $bcrypt->hexdigest;
Same as "digest", but will return the digest in hexadecimal form.
The length of the returned string will be 46 and will only contain
characters from the ranges '0'..'9' and 'a'..'f'.
reset
$bcrypt->reset;
Resets the object to the same internal state it was in when it was
constructed.
SEE ALSO
Digest, Crypt::Eksblowfish::Bcrypt, Data::Entropy::Algorithms
AUTHOR
James Aitken jaitken@cpan.org
CONTRIBUTORS
* Chase Whitener capoeira@cpan.org
COPYRIGHT AND LICENSE
This software is copyright (c) 2012 by James Aitken.
This is free software; you can redistribute it and/or modify it under
the same terms as the Perl 5 programming language system itself.