NAME

Digest::Bcrypt - Perl interface to the bcrypt digest algorithm

SYNOPSIS

Provides an interface to the bcrypt digest algorithm.

This module subclasses Digest::base and can be used either directly or through the Digest meta-module. Using the latter is recommended.

It is mostly a wrapper around Crypt::Eksblowfish::Bcrypt.

USAGE

    # via the Digest module (recommended)
    use Digest;

    my $bcrypt = Digest->new('Bcrypt');

    # $cost is an integer between 1 and 31
    $bcrypt->cost($cost);

    # $salt must be exactly 16 octets long
    $bcrypt->salt($salt);

    $bcrypt->add($data);

    $digest = $bcrypt->digest;
    $digest = $bcrypt->hexdigest;
    $digest = $bcrypt->b64digest;

    # bcrypt's own non-standard base64 dictionary
    $digest = $bcrypt->bcrypt_b64digest;

    # [...]

    # Using the module directly (same interface as above)

    use Digest::Bcrypt;

    my $bcrypt = Digest::Bcrypt->new();

METHODS

The object-oriented interface to Digest::Bcrypt is mostly identical to that of Digest, with a few additions.

Notably you must set a salt exactly 16 octets in length, and you must provide a cost in the range '1'..'31'.

new

    my $bcrypt = Digest->new('Bcrypt');

Creates a new Digest::Bcrypt object.

You can also use this module directly

    my $bcrypt = Digest::Bcrypt->new();

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

salt

    $bcrypt->salt($salt);

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 randomised salt.

When called with no arguments, will return the whatever is the current salt

cost

    $bcrypt->cost($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, will return the current cost

digest

    $bcrypt->digest;

Return the binary digest for the message.

The returned string will be 23 bytes long.

hexdigest

    $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'.

b64digest

    $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

    $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 $bcrypt->clone;

Creates a clone of the Digest::Bcrypt object, and returns it.

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>

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.

cpanm Digest::Bcrypt

perl -MCPAN -e shell
install Digest::Bcrypt