NAME
Crypt::XTEA::LE - Implementation of the eXtended Tiny Encryption Algorithm with little-endian support
VERSION
version 0.0107
SYNOPSIS
use Crypt::XTEA:LE;
use Crypt::CBC;
my $xtea = Crypt::XTEA:LE->new( $key, 32, little_endian => 1 );
my $cbc = Crypt::CBC->new( -cipher => $xtea );
my $text = 'The quick brown fox jumps over the lazy dog.';
my $cipher_text = $cbc->encrypt( $text );
my $plain_text = $cbc->decrypt( $cipher_text );
DESCRIPTION
In cryptography, XTEA (eXtended TEA) is a block cipher designed to correct weaknesses in TEA. The cipher's designers were David Wheeler and Roger Needham of the Cambridge Computer Laboratory, and the algorithm was presented in an unpublished technical report in 1997 (Needham and Wheeler, 1997). It is not subject to any patents.
Like TEA, XTEA is a 64-bit block Feistel cipher with a 128-bit key and a suggested 64 Feistel rounds (i.e 32 cycles). Crypt::XTEA::LE, uses the recommended value of 32 by default.
This module implements XTEA encryption. It supports the Crypt::CBC interface, with the following functions.
METHODS
keysize
Returns the maximum XTEA key size, 16 bytes.
blocksize
Returns the XTEA::LE block size, which is 8 bytes. This function exists so that Crypt::XTEA:LE can work with Crypt::CBC.
new
my $xtea = Crypt::XTEA::LE->new( $key, $rounds, little_endian => 0 );
This creates a new Crypt::XTEA::LE object with the specified key. The optional rounds parameter specifies the number of rounds of encryption to perform, and defaults to 32. If the key is provided as a scalar string, it is split to a series of 4x big-endian 32-bit integers. If little-endian order is required instead, the optional little_endian key can be set to 1.
encrypt
$cipher_text = $xtea->encrypt($plain_text);
Encrypts blocksize() bytes of $plain_text and returns the corresponding ciphertext. By default, the block is interpreted as 2x big-endian 32-bit integers. if little_endian => 1 was specified during new(), the block will be split into two little-endian integers instead.
decrypt
$plain_text = $xtea->decrypt($cipher_text);
Decrypts blocksize() bytes of $cipher_text and returns the corresponding plaintext. By default, the block is interpreted as 2x big-endian 32-bit integers. if little_endian => 1 was specified during new(), the block will be split into two little-endian integers instead.
SEE ALSO
Based on Crypt::XTEA
AUTHOR
Kars Wang <jahiy@cpan.org> Ahmad Fatoum <athreef@cpan.org>
COPYRIGHT AND LICENSE
This software is copyright (c) 2015 by Kars Wang.
This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.