\chapter{Cryptographic Services}
\index{cryptography}

The modules described in this chapter implement various algorithms of
a cryptographic nature.  They are available at the discretion of the
installation.  Here's an overview:

\begin{description}

\item[md5]
--- RSA's MD5 message digest algorithm.

\item[mpz]
--- Interface to the GNU MP library for arbitrary precision arithmetic.

\item[rotor]
--- Enigma-like encryption and decryption.

\end{description}

Hardcore cypherpunks will probably find the Python Cryptography Kit of
further interest; the package adds built-in modules for DES and IDEA
encryption, and provides a Python module for reading and decrypting
PGP files.  The Python Cryptography Kit is not distributed with Python
but available separately.  See the URL
\file{http://www.cs.mcgill.ca/\%7Efnord/crypt.html} for more information.
\index{PGP}
\indexii{DES}{cipher}
\indexii{IDEA}{cipher}
\index{Python Cryptography Kit}
