Digest::SHA::PurePerl is a complete implementation of the NIST
Secure Hash Standard.  It gives Perl programmers a convenient way
to calculate SHA-1, SHA-224, SHA-256, SHA-384, and SHA-512 message
digests.  The module can handle all types of input, including
partial-byte data.
Digest::SHA::PurePerl is written entirely in Perl.  If your platform
has a C compiler, you should install the functionally-equivalent
(but much faster) Digest::SHA module.

WWW: http://search.cpan.org/dist/Digest-SHA-PurePerl