This is Debian GNU/Linux's prepackaged version of Digest::SHA1
(renamed to be libdigest-sha1-perl).

The Digest::SHA1 module allows you to use the NIST SHA-1 message
digest algorithm from within Perl programs.  The algorithm takes as
input a message of arbitrary length and produces as output a 160-bit
"fingerprint" or "message digest" of the input.

SHA1 is described at <http://www.itl.nist.gov/fipspubs/fip180-1.htm>

This package was put together by Michael Alan Dorman
<mdorman@debian.org>.  The library is available from the Comprehensive
Perl Archive Network (CPAN). Visit <URL:http://www.perl.com/CPAN/> to
find a CPAN site near you.

The only change for the Debian package was the addition of the debian/
files.

The Digest::SHA1 copright is as follows:

Copyright 1999-2001 Gisle Aas.
Copyright 1997 Uwe Hollerbach.

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