[Cryptography] OpenSSL CSPRNG work

[Theodore Ts'o]

On Sun, Jul 02, 2017 at 10:16:17PM -0700, Jon Callas wrote:
> 
> > On Jul 2, 2017, at 2:46 PM, Mark Steward <marksteward at gmail.com> wrote:
> > 
> > I think Watson Ladd's point will be missed so to call it out again: in the context of this discussion, arc4random is a placeholder for ChaCha20 or newer replacement, as it is in OpenBSD 5.5+. It doesn't mean RC4.
> 
> I'm sorry.
> 
> arc4random(3) is a function in stdlib.h. Look at the man pages.

Yes, *please* look at the man pages.

HISTORY
     These functions first appeared in OpenBSD 2.1.

     The original version of this random number generator used
     the RC4 (also known as ARC4) algorithm.  In OpenBSD 5.5 it
     was replaced with the ChaCha20 cipher, and it may be
     replaced again in the future as cryptographic techniques
     advance.  A good mnemonic is “A Replacement Call for
     Random”.

					- Ted