File Coverage

blib/lib/File/KDBX/Cipher.pm

Criterion	Covered	Total	%
statement	82	102	80.3
branch	17	36	47.2
condition	5	16	31.2
subroutine	20	30	66.6
pod	19	19	100.0
total	143	203	70.4

package File::KDBX::Cipher;
# ABSTRACT: A block cipher mode or cipher stream

use warnings;
use strict;

use Devel::GlobalDestruction;
use File::KDBX::Constants qw(:cipher :random_stream);
use File::KDBX::Error;
use File::KDBX::Util qw(:class erase format_uuid);
use Module::Load;
use Scalar::Util qw(looks_like_number);
use namespace::clean;

our $VERSION = '0.906'; # VERSION

my %CIPHERS;


has 'uuid',         is => 'ro';
has 'stream_id',    is => 'ro';
has 'key',          is => 'ro';
has 'iv',           is => 'ro';
sub iv_size     {  0 }
sub key_size    { -1 }
sub block_size  {  0 }
sub algorithm   { $_[0]->{algorithm} or throw 'Block cipher algorithm is not set' }


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

    return $class->new_from_uuid(delete $args{uuid}, %args) if defined $args{uuid};
    return $class->new_from_stream_id(delete $args{stream_id}, %args) if defined $args{stream_id};

    throw 'Must pass uuid or stream_id';
}

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

    $args{key} or throw 'Missing encryption key';
    $args{iv}  or throw 'Missing encryption IV';

    my $formatted_uuid = format_uuid($uuid);

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

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

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

    $args{key} or throw 'Missing encryption key';

    my $cipher = $CIPHERS{$id} or throw "Unsupported stream cipher ($id)", id => $id;
    ($class, my %registration_args) = @$cipher;

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


sub init { $_[0] }

sub DESTROY { !in_global_destruction and erase \$_[0]->{key} }


sub encrypt { die 'Not implemented' }


sub decrypt { die 'Not implemented' }


sub finish { '' }


sub encrypt_finish {
    my $self = shift;
    my $out = $self->encrypt(@_);
    $out .= $self->finish;
    return $out;
}


sub decrypt_finish {
    my $self = shift;
    my $out = $self->decrypt(@_);
    $out .= $self->finish;
    return $out;
}


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

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

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

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

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


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

BEGIN {
    __PACKAGE__->register(CIPHER_UUID_AES128,   'CBC',    algorithm => 'AES',     key_size => 16);
    __PACKAGE__->register(CIPHER_UUID_AES256,   'CBC',    algorithm => 'AES',     key_size => 32);
    __PACKAGE__->register(CIPHER_UUID_SERPENT,  'CBC',    algorithm => 'Serpent', key_size => 32);
    __PACKAGE__->register(CIPHER_UUID_TWOFISH,  'CBC',    algorithm => 'Twofish', key_size => 32);
    __PACKAGE__->register(CIPHER_UUID_CHACHA20, 'Stream', algorithm => 'ChaCha');
    __PACKAGE__->register(CIPHER_UUID_SALSA20,  'Stream', algorithm => 'Salsa20');
    __PACKAGE__->register(STREAM_ID_CHACHA20,   'Stream', algorithm => 'ChaCha');
    __PACKAGE__->register(STREAM_ID_SALSA20,    'Stream', algorithm => 'Salsa20');
}

1;

__END__