#!/opt/perl/bin/perl -w

use strict;
use Crypt::Twofish2;

binmode STDIN;

sub padkey {
    my $key = shift;
    if (length($key) < 32) {
	return $key . substr("\000" x 32, 0, 32 - length($key));
    } else {
	return substr($key, 0, 32);
    }
}

scalar(@ARGV) or die "usage: tfdec key\n";
my $key = padkey($ARGV[0]);

my $crypted = "";
while (read(STDIN, my $tmp, 8192)) {
    $crypted .= $tmp;
}

my $cipher = Crypt::Twofish2->new($key, Crypt::Twofish2::MODE_CBC) or
	die "$!\n";
my $plaintext = $cipher->decrypt($crypted) or die "$!\n";

$plaintext =~ s/\000+$//;
print $plaintext;
.