NAME

Crypt::Twofish - The Twofish Encryption Algorithm

SYNOPSIS

use Crypt::Twofish;

$cipher = Crypt::Twofish->new($key);

$ciphertext = $cipher->encrypt($plaintext);

$plaintext = $cipher->decrypt($ciphertext);

DESCRIPTION

Twofish is a 128-bit symmetric block cipher with a variable length (128, 192, or 256-bit) key, developed by Counterpane Labs. It is unpatented and free for all uses, as described at <URL:http://www.counterpane.com/twofish.html>.

This module implements Twofish encryption. It supports the Crypt::CBC interface, with the functions described below. It also provides an interface that is call-compatible with Crypt::Twofish 1.0, but its use in new code is strongly discouraged.

Functions

blocksize
Returns the size (in bytes) of the block (16, in this case).
keysize
Returns the size (in bytes) of the key. Although the module understands 128, 192, and 256-bit keys, it returns 16 for compatibility with Crypt::CBC.
new($key)
This creates a new Crypt::Twofish object with the specified key (which should be 16, 24, or 32 bytes long).
encrypt($data)
Encrypts blocksize() bytes of $data and returns the corresponding ciphertext.
decrypt($data)
Decrypts blocksize() bytes of $data and returns the corresponding plaintext.

SEE ALSO

Crypt::CBC, Crypt::Blowfish, Crypt::TEA

ACKNOWLEDGEMENTS

Nishant Kakani
For writing Crypt::Twofish 1.0 (this version is a complete rewrite).
Tony Cook
For making the module work under Activeperl, testing on several platforms, and suggesting that I probe for features via %Config.

AUTHOR

Abhijit Menon-Sen <ams@wiw.org>

Copyright 2001 Abhijit Menon-Sen. All rights reserved.

This software is distributed under the terms of the Artistic License <URL:http://ams.wiw.org/code/artistic.txt>.