crypt::des_ede3(3pm) [debian man page]

Crypt::DES_EDE3(3pm)					User Contributed Perl Documentation				      Crypt::DES_EDE3(3pm)

NAME

       Crypt::DES_EDE3 - Triple-DES EDE encryption/decryption

SYNOPSIS

	   use Crypt::DES_EDE3;
	   my $ede3 = Crypt::DES_EDE3->new($key);
	   $ede3->encrypt($block);

DESCRIPTION

       Crypt::DES_EDE3 implements DES-EDE3 encryption. This is triple-DES encryption where an encrypt operation is encrypt-decrypt-encrypt, and
       decrypt is decrypt-encrypt-decrypt. This implementation uses Crypt::DES to do its dirty DES work, and simply provides a wrapper around that
       module: setting up the individual DES ciphers, initializing the keys, and performing the encryption/decryption steps.

       DES-EDE3 encryption requires a key size of 24 bytes.

       You're probably best off not using this module directly, as the encrypt and decrypt methods expect 8-octet blocks. You might want to use
       the module in conjunction with Crypt::CBC, for example. This would be DES-EDE3-CBC, or triple-DES in outer CBC mode.

USAGE

       $ede3 = Crypt::DES_EDE3->new($key)

       Creates a new Crypt::DES_EDE3 object (really, a collection of three DES ciphers), and initializes each cipher with part of $key, which
       should be at least 24 bytes. If it's longer than 24 bytes, the extra bytes will be ignored.

       Returns the new object.

       $ede3->encrypt($block)

       Encrypts an 8-byte block of data $block using the three DES ciphers in an encrypt-decrypt-encrypt operation.

       Returns the encrypted block.

       $ede3->decrypt($block)

       Decrypts an 8-byte block of data $block using the three DES ciphers in a decrypt-encrypt-decrypt operation.

       Returns the decrypted block.

       $ede3->blocksize

       Returns the block size(8).

       $ede3->keysize

       Returns the key size(24).

LICENSE

       Crypt::DES_EDE3 is free software; you may redistribute it and/or modify it under the same terms as Perl itself.

AUTHOR &; COPYRIGHTS
       Crypt::DES_EDE3 is Copyright 2001 Benjamin Trott, ben@rhumba.pair.com. All rights reserved.

perl v5.8.8							    2001-09-15						      Crypt::DES_EDE3(3pm)

Crypt::Eksblowfish::Blowfish(3pm)			User Contributed Perl Documentation			 Crypt::Eksblowfish::Blowfish(3pm)

NAME

       Crypt::Eksblowfish::Blowfish - Blowfish block cipher via Eksblowfish engine

SYNOPSIS

	       use Crypt::Eksblowfish::Blowfish;

	       $block_size = Crypt::Eksblowfish::Blowfish->blocksize;
	       $key_size = Crypt::Eksblowfish::Blowfish->keysize;

	       $cipher = Crypt::Eksblowfish::Blowfish->new($key);

	       $block_size = $cipher->blocksize;
	       $ciphertext = $cipher->encrypt($plaintext);
	       $plaintext = $cipher->decrypt($ciphertext);

	       $p_array = $cipher->p_array;
	       $s_boxes = $cipher->s_boxes;
	       if($cipher->is_weak) { ...

DESCRIPTION

       An object of this type encapsulates a keyed instance of the Blowfish block cipher, ready to encrypt and decrypt.

       Blowfish is a symmetric cipher algorithm designed by Bruce Schneier in 1993.  It operates on 64-bit blocks, and takes a variable-length key
       from 32 bits (4 octets) to 448 bits (56 octets) in increments of 8 bits (1 octet).

       This implementation of Blowfish uses an encryption engine that was originally implemented in order to support Eksblowfish, which is a
       variant of Blowfish modified to make keying particularly expensive.  See Crypt::Eksblowfish for that variant; this class implements the
       original Blowfish.

CLASS METHODS

       Crypt::Eksblowfish::Blowfish->blocksize
	   Returns 8, indicating the Blowfish block size of 8 octets.  This method may be called on either the class or an instance.

       Crypt::Eksblowfish::Blowfish->keysize
	   Returns 0, indicating that the key size is variable.  This situation is handled specially by "Crypt::CBC".

CONSTRUCTOR

       Crypt::Eksblowfish::Blowfish->new(KEY)
	   Performs key setup on a new instance of the Blowfish algorithm, returning the keyed state.  The KEY may be any length from 4 octets to
	   56 octets inclusive.

	   You may occasionally come across an alleged Blowfish key that is outside this length range, and so is rejected by this constructor.
	   Blowfish can internally process a key of any octet length up to 72 octets, and some implementations don't enforce the official length
	   restrictions.  If it is necessary for compatibility, a key of out-of-range length can be processed by Crypt::Eksblowfish::Uklblowfish.

METHODS

       $cipher->blocksize
	   Returns 8, indicating the Blowfish block size of 8 octets.  This method may be called on either the class or an instance.

       $cipher->encrypt(PLAINTEXT)
	   PLAINTEXT must be exactly eight octets.  The block is encrypted, and the ciphertext is returned.

       $cipher->decrypt(CIPHERTEXT)
	   CIPHERTEXT must be exactly eight octets.  The block is decrypted, and the plaintext is returned.

       $cipher->p_array
       $cipher->s_boxes
	   These methods extract the subkeys from the keyed cipher.  This is not required in ordinary operation.  See the superclass
	   Crypt::Eksblowfish::Subkeyed for details.

       $cipher->is_weak
	   This method checks whether the cipher has been keyed with a weak key.  It may be desired to avoid using weak keys.  See the superclass
	   Crypt::Eksblowfish::Subkeyed for details.

SEE ALSO

       Crypt::Eksblowfish, Crypt::Eksblowfish::Subkeyed, Crypt::Eksblowfish::Uklblowfish, <http://www.schneier.com/blowfish.html>

AUTHOR

       Eksblowfish guts originally by Solar Designer (solar at openwall.com).

       Modifications and Perl interface by Andrew Main (Zefram) <zefram@fysh.org>.

COPYRIGHT

       Copyright (C) 2006, 2007, 2008, 2009, 2010 Andrew Main (Zefram) <zefram@fysh.org>

       The original Eksblowfish code (in the form of crypt()) from which this module is derived is in the public domain.  It may be found at
       <http://www.openwall.com/crypt/>.

LICENSE

       This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

perl v5.14.2							    2011-11-15					 Crypt::Eksblowfish::Blowfish(3pm)