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.

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@toroid.org>