Crypt::HCE_SHA - Perl extension implementing one way hash chaining encryption using SHA

       Eric Estabrooks, eric@urbanrage.com

       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

       Crypt::HCE_SHA - Perl extension implementing one way hash chaining encryption using SHA

perl(1).

perl v5.36.0                                       2022-10-13                                       HCE_SHA(3pm)

         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);

         $hce_sha = Crypt::HCE_SHA->new("key", "random", 256);  # use SHA256 instead of SHA1