NAME

       Math::Prime::Util::ChaCha - Pure Perl ChaCha20 CSPRNG

VERSION

       Version 0.70

SYNOPSIS

DESCRIPTION

       A pure Perl implementation of ChaCha20 with a CSPRNG interface.

FUNCTIONS

   csrand
       Takes a binary string as input and seeds the internal CSPRNG.

   srand
       A method for sieving the CSPRNG with a small value.  This will not be secure but can be
       useful for simulations and emulating the system "srand".

       With no argument, chooses a random number, seeds and returns the number.  With a single
       integer argument, seeds and returns the number.

   irand
       Returns a random 32-bit integer.

   irand64
       Returns a random 64-bit integer.

   random_bytes
       Takes an unsigned number "n" as input and returns that many random bytes as a single
       binary string.

AUTHORS

       Dana Jacobsen <dana@acm.org>

ACKNOWLEDGEMENTS

       Daniel J. Bernstein wrote the ChaCha family of stream ciphers in 2008 as an update to the
       popular Salsa20 cipher from 2005.

       RFC7539: "ChaCha20 and Poly1305 for IETF Protocols" was used to create both the C and Perl
       implementations.  Test vectors from that document are used here as well.

       For final optimizations I got ideas from Christopher Madsen's Crypt::Salsa20 for how to
       best work around some of Perl's aggressive dynamic typing.  Our core is still about 20%
       slower than Salsa20.

COPYRIGHT

       Copyright 2017 by Dana Jacobsen <dana@acm.org>

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