sub encrypt (\$$) {
    my ($self,$data) = @_;
    $self->start('encrypting');
    my $result = $self->crypt($data);
    $result .= $self->finish;
    $result;
}

sub decrypt (\$$){
    my ($self,$data) = @_;
    $self->start('decrypting');
    my $result = $self->crypt($data);
    $result .= $self->finish;
    $result;
}