File Coverage

blib/lib/File/KDBX/KDF.pm

Criterion	Covered	Total	%
statement	61	70	87.1
branch	9	14	64.2
condition	7	14	50.0
subroutine	15	19	78.9
pod	8	8	100.0
total	100	125	80.0

package File::KDBX::KDF;
# ABSTRACT: A key derivation function

use warnings;
use strict;

use Crypt::PRNG qw(random_bytes);
use File::KDBX::Constants qw(:version :kdf);
use File::KDBX::Error;
use File::KDBX::Util qw(format_uuid);
use Module::Load;
use Scalar::Util qw(blessed);
use namespace::clean;

our $VERSION = '0.905'; # VERSION

my %KDFS;


sub new {
    my $class = shift;
    my %args = @_;

    my $uuid = $args{+KDF_PARAM_UUID} //= delete $args{uuid} or throw 'Missing KDF UUID', args => \%args;
    my $formatted_uuid = format_uuid($uuid);

    my $kdf = $KDFS{$uuid} or throw "Unsupported KDF ($formatted_uuid)", uuid => $uuid;
    ($class, my %registration_args) = @$kdf;

    load $class;
    my $self = bless {KDF_PARAM_UUID() => $uuid}, $class;
    return $self->init(%args, %registration_args);
}


sub init {
    my $self = shift;
    my %args = @_;

    @$self{keys %args} = values %args;

    return $self;
}


sub uuid { $_[0]->{+KDF_PARAM_UUID} }


sub seed { die 'Not implemented' }


sub transform {
    my $self = shift;
    my $key  = shift;

    if (blessed $key && $key->can('raw_key')) {
        return $self->_transform($key->raw_key) if $self->uuid eq KDF_UUID_AES;
        return $self->_transform($key->raw_key($self->seed, @_));
    }

    return $self->_transform($key);
}

sub _transform { die 'Not implemented' }


sub randomize_seed {
    my $self = shift;
    $self->{+KDF_PARAM_AES_SEED} = random_bytes(length($self->seed));
}


sub register {
    my $class   = shift;
    my $id      = shift;
    my $package = shift;
    my @args    = @_;

    my $formatted_id = format_uuid($id);
    $package = "${class}::${package}" if $package !~ s/^\+// && $package !~ /^\Q${class}::\E/;

    my %blacklist = map { File::KDBX::Util::uuid($_) => 1 } split(/,/, $ENV{FILE_KDBX_KDF_BLACKLIST} // '');
    if ($blacklist{$id} || $blacklist{$package}) {
        alert "Ignoring blacklisted KDF ($formatted_id)", id => $id, package => $package;
        return;
    }

    if (defined $KDFS{$id}) {
        alert "Overriding already-registered KDF ($formatted_id) with package $package",
            id      => $id,
            package => $package;
    }

    $KDFS{$id} = [$package, @args];
}


sub unregister {
    delete $KDFS{$_} for @_;
}

BEGIN {
    __PACKAGE__->register(KDF_UUID_AES,                     'AES');
    __PACKAGE__->register(KDF_UUID_AES_CHALLENGE_RESPONSE,  'AES');
    __PACKAGE__->register(KDF_UUID_ARGON2D,                 'Argon2');
    __PACKAGE__->register(KDF_UUID_ARGON2ID,                'Argon2');
}

1;

__END__