fortuna: an improved PRNG

This is a Go implementation of the Fortuna PRNG[1]. It can be used
by applications which do not trust the operating system's RNG
facilities or in cases where acquiring random data via the operating
system's facilities may not be an option, or where the operating
system relies on a hardware RNG or other single point of
compromise/failure.

The PRNG works by sending random events to the PRNG, such as random
network traffic, key presses, etc. This is accomplished via sources;
two sources are provided -- one provides a channel which receives
byte slices, the other providing a standard io.Writer interface.

This source code may be fetched from the primary repository[2] at
via Mercurial. There are backups on Github[3] and Bitbucket[4] (via Mercurial).

Currently in progress is an example daemon providing a PRNG over TCP/IP.

For usage instructions on the `fortuna` package, please see the
README in the package's directory. An implementation that uses
256-bit Twofish and Keccak-256 is provided in the `tunafish` package.


[1] N. Ferguson, B. Schneier, T. Kohno. Cryptography Engineering.
    Wiley, March 2010. pp142-160.
[2] http://hg.tyrfingr.is/kyle/gofortuna 
[3] https://github.com/gokyle/gofortuna
[4] https://bitbucket.org/kisom/gofortuna


LICENSE
=======
Copyright (c) 2013 Kyle Isom <[email protected]>

Permission to use, copy, modify, and distribute this software for any
purpose with or without fee is hereby granted, provided that the above 
copyright notice and this permission notice appear in all copies.

THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.