NAME

       Crypt::Blowfish - Perl Blowfish encryption module

SYNOPSIS

         use Crypt::Blowfish;
         my $cipher = new Crypt::Blowfish $key;
         my $ciphertext = $cipher->encrypt($plaintext);
         my $plaintext  = $cipher->decrypt($ciphertext);

         You probably want to use this in conjunction with
         a block chaining module like Crypt::CBC.

DESCRIPTION

       Blowfish is capable of strong encryption and can use key sizes up to 56 bytes (a 448 bit
       key).  You're encouraged to take advantage of the full key size to ensure the strongest
       encryption possible from this module.

       Crypt::Blowfish has the following methods:

        blocksize()
        keysize()
        encrypt()
        decrypt()

FUNCTIONS

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

           Crypt::Blowfish doesn't return a key size due to its ability to use variable-length
           keys.  More accurately, it shouldn't, but it does anyway to play nicely with others.

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

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

       encrypt
                   my $cipher = new Crypt::Blowfish $key;
                   my $ciphertext = $cipher->encrypt($plaintext);

           This function encrypts $plaintext and returns the $ciphertext where $plaintext and
           $ciphertext must be of "blocksize()" bytes.  (hint:  Blowfish is an 8 byte block
           cipher)

       decrypt
                   my $cipher = new Crypt::Blowfish $key;
                   my $plaintext = $cipher->decrypt($ciphertext);

           This function decrypts $ciphertext and returns the $plaintext where $plaintext and
           $ciphertext must be of "blocksize()" bytes.  (hint:  see previous hint)

EXAMPLE

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

PLATFORMS

               Please see the README document for platforms and performance
               tests.

NOTES

       The module is capable of being used with Crypt::CBC.  You're encouraged to read the
       perldoc for Crypt::CBC if you intend to use this module for Cipher Block Chaining modes.
       In fact, if you have any intentions of encrypting more than eight bytes of data with this,
       or any other block cipher, you're going to need some type of block chaining help.
       Crypt::CBC tends to be very good at this.  If you're not going to encrypt more than eight
       bytes, your data must be exactly eight bytes long.  If need be, do your own padding. "\0"
       as a null byte is perfectly valid to use for this.

SEE ALSO

       Crypt::CBC, Crypt::DES, Crypt::IDEA

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

COPYRIGHT

       The implementation of the Blowfish algorithm was developed by, and is copyright of, A.M.
       Kuchling.

       Other parts of the perl extension and module are copyright of Systemics Ltd (
       http://www.systemics.com/ ).

       Code revisions, updates, and standalone release are copyright 1999-2010 W3Works, LLC.

AUTHOR

       Original algorithm, Bruce Shneier.  Original implementation, A.M.  Kuchling.  Original
       Perl implementation, Systemics Ltd.  Current maintenance by W3Works, LLC.

       Current revision and maintainer:  Dave Paris <amused@pobox.com>