This message generated a parse failure. Raw output follows here. Please use 'back' to navigate. From devnull@lkml.org Sun May 19 07:36:15 2024 Received: from entropy.muc.muohio.edu (IDENT:root@entropy.muc.muohio.edu [134.53.213.10]) by herbie.ucs.indiana.edu (8.9.3/8.9.3) with ESMTP id QAA26147 for ; Tue, 1 Jun 1999 16:28:56 -0500 (EST) Received: from vger.rutgers.edu (vger.rutgers.edu [128.6.190.2]) by entropy.muc.muohio.edu (8.8.7/8.8.7) with ESMTP id RAA31737; Tue, 1 Jun 1999 17:28:51 -0400 Received: by vger.rutgers.edu via listexpand id ; Tue, 1 Jun 1999 16:09:27 -0400 Received: by vger.rutgers.edu id ; Tue, 1 Jun 1999 16:07:32 -0400 Received: from lesser-magoo.lcs.mit.edu ([18.111.0.112]:12827 "EHLO lesser-magoo.lcs.mit.edu") by vger.rutgers.edu with ESMTP id ; Tue, 1 Jun 1999 16:04:39 -0400 Received: from miris.lcs.mit.edu (cananian@miris.lcs.mit.edu [18.111.0.89]) by lesser-magoo.lcs.mit.edu (8.8.7/8.8.7) with ESMTP id RAA09640; Tue, 1 Jun 1999 17:11:42 -0400 Date: Tue, 1 Jun 1999 17:11:42 -0400 (EDT) From: "C. Scott Ananian" X-Sender: cananian@miris.lcs.mit.edu To: David Whysong Cc: Florian Weimer , linux-kernel@vger.rutgers.edu Subject: Re: /dev/random and /dev/psaux: too much entropy assumed? In-Reply-To: Message-Id: Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-kernel@vger.rutgers.edu Precedence: bulk X-Loop: majordomo@vger.rutgers.edu X-Orcpt: rfc822;linux-kernel-outgoing-dig On Tue, 1 Jun 1999, David Whysong wrote: > On Tue, 1 Jun 1999, C. Scott Ananian wrote: > >On 1 Jun 1999, Florian Weimer wrote: > >> further question: The implementation of /dev/random assumes that the > >> output of the SHA-1 hash function is random for random (or almost random) > >> input. Neither the people on sci.crypt nor I know of any analysis > >> of SHA-1 in this direction (which doesn't prove anything of course). [...] > >Patent issues, I strongly suspect. And most of the applications for > >/dev/random don't actually require 'uniformly distributed' output (which > >is my guess as to what you mean by 'random'); rather they require > >'unguessable' output. SHA-1, being a strong one-way function, provides > >unguessable output. [...] > What? /dev/random not uniform? You've got to be kidding! Careful, I didn't quite say that. The original poster said "he didn't know of any analysis of SHA-1" and I said "it probably doesn't matter". Neither of us are claiming that SHA-1 isn't uniform. I personally doubt that you'll find any *specific* proofs that SHA-1 is uniform because I believe that there are *general* proofs relating security to uniformity, and then *specific* proofs of certain security properities to SHA-1. The cryptography community generally has a much higher standard of proof than the statistical community, and I would be very very surprised indeed to find a *secure* algorithm that was *not* statistically random. On the other hand, there are many uniformly random sources that are not secure. --s @ @ =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-oOO-(_)-OOo-=-=-=-=-= C. Scott Ananian: cananian@lcs.mit.edu / Declare the Truth boldly and Laboratory for Computer Science/Crypto / without hindrance. Massachusetts Institute of Technology /META-PARRESIAS AKOLUTOS:Acts 28:31 -.-. .-.. .. ..-. ..-. --- .-. -.. ... -.-. --- - - .- -. .- -. .. .- -. PGP key available via finger and from http://www.pdos.lcs.mit.edu/~cananian Serbian PLO quiche AES Shoal Bay NORAD Albanian bomb Japan nuclear radar AK-47 SEAL Team 6 spy Soviet Semtex Hager fissionable Qaddafi - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.rutgers.edu Please read the FAQ at http://www.tux.org/lkml/