Sapphire.cpp -- Gpl compatible? DFSG-free?
In the source code of the package my team is managing there is this one file.
I'm wondering whether it is DFSG-free and weather GPL v2 only code can
link it with/(out) exception.
Here is the full copyright statement
/* sapphire.cpp -- the Saphire II stream cipher class.
Dedicated to the Public Domain the author and inventor:
(Michael Paul Johnson). This code comes with no warranty.
Use it at your own risk.
Ported from the Pascal implementation of the Sapphire Stream
Cipher 9 December 1994.
Added hash pre- and post-processing 27 December 1994.
Modified initialization to make index variables key dependent,
made the output function more resistant to cryptanalysis,
and renamed to Sapphire II 2 January 1995
With best regards
Dmitrijs Ledkovs (for short Dima),
Ледков Дмитрий Юрьевич