NAME

Crypt::AppleTwoFish -- an Apple iTMS internal key descrambling algorithm

DESCRIPTION

This code appears to have only cursory resemblance to Bruce Schneier's blowfish and twofish algorithms in that it too has a table-based decoder.

Derivation from FairKeys code by Jon Lech Johanson at nanocrew.net. If you don't know what that is, don't bother looking here further. This is a Pure Perl implementation. I doubt there is any need for xs coding for what would mainly be processing 16 bytes at a time. This code is part of an ongoing effort to clone portions of the Apple iTMS in Perl for portability. See www.hymn-project.org for prior efforts by others.

SYNOPSIS

use Crypt::AppleTwoFish;

my $scrambled_key = '=sixteen uchars=';

my $apple_twofish = new Crypt::AppleTwoFish($scrambled_key);

my $descrambled_key = $apple_twofish->decrypted;

METHODS

new

Call with the key as a scalar argument. The key is generally 16 unsigned chars in length.

decrypted

Returns the unscrambled key.

AUTHOR

From the scramble function and scramble_vector adapted from iTMS.cs, FairKeys 0.5, 
by Jon Lech Johansen, but using the alterate scramble table found by FutureProof.
Perl version from python version: William Herrera B<wherrera@skylightview.com>. 

SUPPORT

Questions, feature requests and bug reports should go to <wherrera@skylightview.com>.

COPYRIGHT

Copyright (c) 2005 William Herrera. All rights reserved. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.