| Crypt-DES documentation | Contained in the Crypt-DES distribution. |
Crypt::DES - Perl DES encryption module
use Crypt::DES;
The module implements the Crypt::CBC interface, which has the following methods
Returns the size (in bytes) of the block cipher.
Returns the size (in bytes) of the key. Optimal size is 8 bytes.
my $cipher = new Crypt::DES $key;
This creates a new Crypt::DES BlockCipher object, using $key,
where $key is a key of keysize() bytes.
my $cipher = new Crypt::DES $key; my $ciphertext = $cipher->encrypt($plaintext);
This function encrypts $plaintext and returns the $ciphertext
where $plaintext and $ciphertext should be of blocksize() bytes.
my $cipher = new Crypt::DES $key; my $plaintext = $cipher->decrypt($ciphertext);
This function decrypts $ciphertext and returns the $plaintext
where $plaintext and $ciphertext should be of blocksize() bytes.
my $key = pack("H16", "0123456789ABCDEF");
my $cipher = new Crypt::DES $key;
my $ciphertext = $cipher->encrypt("plaintex"); # NB - 8 bytes
print unpack("H16", $ciphertext), "\n";
Do note that DES only uses 8 byte keys and only works on 8 byte data blocks. If you're intending to encrypt larger blocks or entire files, please use Crypt::CBC in conjunction with this module. See the Crypt::CBC documentation for proper syntax and use.
Also note that the DES algorithm is, by today's standard, weak encryption. Crypt::Blowfish is highly recommended if you're interested in using strong encryption and a faster algorithm.
Crypt::Blowfish Crypt::IDEA
Bruce Schneier, Applied Cryptography, 1995, Second Edition, published by John Wiley & Sons, Inc.
The implementation of the DES algorithm was developed by, and is copyright of, Eric Young (eay@mincom.oz.au). Other parts of the perl extension and module are copyright of Systemics Ltd ( http://www.systemics.com/ ). Cross-platform work and packaging for single algorithm distribution is copyright of W3Works, LLC.
This single-algorithm package and cross-platform code is maintained by Dave Paris <amused@pobox.com>.
| Crypt-DES documentation | Contained in the Crypt-DES distribution. |
# # Copyright (C) 1995, 1996 Systemics Ltd (http://www.systemics.com/) # All rights reserved. # # Modifications are Copyright (c) 2000, W3Works, LLC # All Rights Reserved. package Crypt::DES; require Exporter; require DynaLoader; use vars qw($VERSION @ISA @EXPORT @EXPORT_OK); @ISA = qw(Exporter DynaLoader); # Items to export into callers namespace by default @EXPORT = qw(); # Other items we are prepared to export if requested @EXPORT_OK = qw(); $VERSION = '2.05'; bootstrap Crypt::DES $VERSION; use strict; use Carp; sub usage { my ($package, $filename, $line, $subr) = caller(1); $Carp::CarpLevel = 2; croak "Usage: $subr(@_)"; } sub blocksize { 8; } sub keysize { 8; } sub new { usage("new DES key") unless @_ == 2; my $type = shift; my $self = {}; bless $self, $type; $self->{'ks'} = Crypt::DES::expand_key(shift); return $self; } sub encrypt { usage("encrypt data[8 bytes]") unless @_ == 2; my ($self,$data) = @_; return Crypt::DES::crypt($data, $data, $self->{'ks'}, 1); } sub decrypt { usage("decrypt data[8 bytes]") unless @_ == 2; my ($self,$data) = @_; return Crypt::DES::crypt($data, $data, $self->{'ks'}, 0); } 1; __END__