NAME¶

Crypt::DES - Perl DES encryption module

SYNOPSIS¶

    use Crypt::DES;

DESCRIPTION¶

The module implements the Crypt::CBC interface, which has the following methods

blocksize =item keysize =item encrypt =item decrypt

FUNCTIONS¶

blocksize

Returns the size (in bytes) of the block cipher.

keysize

Returns the size (in bytes) of the key. Optimal size is 8 bytes.

new

        my $cipher = new Crypt::DES $key;
    

This creates a new Crypt::DES BlockCipher object, using $key, where $key is a key of keysize() bytes.

encrypt

        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.

decrypt

        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.

EXAMPLE¶

        my $key = pack("H16", "0123456789ABCDEF");
        my $cipher = new Crypt::DES $key;
        my $ciphertext = $cipher->encrypt("plaintex");  # NB - 8 bytes
        print unpack("H16", $ciphertext), "\n";

NOTES¶

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.

SEE ALSO¶

Crypt::Blowfish Crypt::IDEA

Bruce Schneier, Applied Cryptography, 1995, Second Edition, published by John Wiley & Sons, Inc.

COPYRIGHT¶

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.

MAINTAINER¶

This single-algorithm package and cross-platform code is maintained by Dave Paris <amused@pobox.com>.