HCE_SHA(3pm) User Contributed Perl Documentation HCE_SHA(3pm)NAME
Crypt::HCE_SHA - Perl extension implementing one way hash chaining encryption using SHA
SYNOPSIS
use Crypt::HCE_SHA;
$hce_sha = Crypt::HCE_SHA->new("SharedSecret", "Random01,39j309ad");
$crypted = $hce_sha->hce_block_encrypt("Encrypt this information");
$info = $hce_sha->hce_block_decrypt($crypted);
$mime_crypted = $hce_sha->hce_block_encode_mime("Encrypt and Base64 this information");
$info = $hce_sha->hce_block_decode_mime($mime_crypted);
DESCRIPTION
This module implements a chaining block cipher using a one way hash. This method of encryption is the same that is used by radius
(RFC2138) and is also described in Applied Cryptography.
Two interfaces are provided in the module. The first is straight block encryption/decryption the second does base64 mime encoding/decoding
of the encrypted/decrypted blocks.
The idea is the the two sides have a shared secret that supplies one of the keys and a randomly generated block of bytes provides the
second key. The random key is passed in cleartext between the two sides.
An example client and server are packaged as modules with this module. They are used in the tests. They can be found in the examples
directory.
Thanks to Jake Angerman for the bug report on the bug in key generation for the chaining portion of the algorithm
AUTHOR
Eric Estabrooks, eric@urbanrage.com
SEE ALSO perl(1).
perl v5.12.4 2011-08-09 HCE_SHA(3pm)
Check Out this Related Man Page
CAST5(3pm) User Contributed Perl Documentation CAST5(3pm)NAME
Crypt::CAST5 - CAST5 block cipher
SYNOPSIS
use Crypt::CBC;
my $crypt = Crypt::CBC->new({
key => "secret key",
cipher => "CAST5",
});
my $message = "All mimsy were the borogoves";
my $ciphertext = $crypt->encrypt($message);
print unpack("H*", $ciphertext), "
";
my $plaintext = $crypt->decrypt($ciphertext);
print $plaintext, "
";
DESCRIPTION
This module provides an implementation of the CAST5 block cipher using compiled C code for increased speed. CAST5 is also known as
CAST-128. It is a product of the CAST design procedure developed by C. Adams and S. Tavares.
The CAST5 cipher is available royalty-free.
FUNCTIONS
blocksize
Returns the CAST5 block size, which is 8 bytes. This function exists so that Crypt::CAST5 can work with Crypt::CBC.
keysize
Returns the maximum CAST5 key size, 16 bytes.
new
$cast5 = Crypt::CAST5->new($key);
Create a new encryption object. If the optional key parameter is given, it will be passed to the init() function.
init
$cast5->init($key);
Set or change the encryption key to be used. The key must be from 40 bits (5 bytes) to 128 bits (16 bytes) in length. Note that if the key
used is 80 bits or less, encryption and decryption will be somewhat faster.
It is best for the key to be random binary data, not something printable like a password. A message digest function may be useful for
converting a password to an encryption key; see Digest::SHA1 or Digest::MD5. Note that Crypt::CBC runs the given "key" through MD5 to get
the actual encryption key.
encrypt
$ciphertext = $cast5->encrypt($plaintext);
Encrypt a block of plaintext using the current encryption key, and return the corresponding ciphertext. The input must be 8 bytes long, and
the output has the same length. Note that the encryption is in ECB mode, which means that it encrypts each block independently. That can
leave you vulnerable to dictionary attacks, so it is generally best to use some form of chaining between blocks; see Crypt::CBC.
decrypt
$plaintext = $cast5->decrypt($ciphertext);
Decrypt the ciphertext and return the corresponding plaintext.
SEE ALSO
RFC 2144, "The CAST-128 Encryption Algorithm", C. Adams, May 1997
Crypt::CBC
AUTHOR
Bob Mathews, <bobmathews@alumni.calpoly.edu>
COPYRIGHT AND LICENSE
Copyright (C) 2002-2006 Bob Mathews
This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.
perl v5.14.2 2006-07-01 CAST5(3pm)