Digest/SHA version 0.9
======================

The Digest::SHA module provides a Perl interface to all variants
of the Secure Hash Algorithm specified in the current NIST Secure
Hash Standard (FIPS PUB 180-2).  In other words, the module supports
SHA-1, SHA-256, SHA-384, and SHA-512.  The routines underlying
Digest::SHA are written in C for speed.

Whereas most message digest packages are restricted to byte-oriented
data, the full SHA standard calls for bit-oriented inputs as well.
The Digest::SHA module addresses both types of input, and allows
digest calculations to be performed directly, or iteratively in
stages.

The underlying C code is designed to be portable, and requires no
special libraries beyond those found with typical compilers.
However, if your compiler can't handle 64-bit integral types (i.e.
long long), the package will omit support for SHA-384 and SHA-512.

The SHA algorithm code maps as closely as possible to the NIST
specification in the interest of achieving correctness.  Later
versions of this module will focus on additional performance
optimizations.

The tests subdirectory (t/*.t) contains an extensive set of SHA
vectors compiled from various sources.  Of particular interest are
the NIST vectors, which examine a large variety of bit-strings and
byte-strings.  Also useful are the bit-vectors specified by Jim
Gillogly, which check the behavior of implementations for large
inputs (i.e. when input strings exceed length 2^32).

INSTALLATION

To install this module type the following:

   perl Makefile.PL
   make
   make test
   make install

DEPENDENCIES

   None.

COPYRIGHT AND LICENCE

Copyright (C) 2003 Mark Shelor

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