From owner-freebsd-numerics@FreeBSD.ORG Tue Mar 17 18:18:52 2015 Return-Path: Delivered-To: freebsd-numerics@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 4A143F5D; Tue, 17 Mar 2015 18:18:52 +0000 (UTC) Received: from mail-yh0-x22f.google.com (mail-yh0-x22f.google.com [IPv6:2607:f8b0:4002:c01::22f]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 023A8309; Tue, 17 Mar 2015 18:18:52 +0000 (UTC) Received: by yhpt93 with SMTP id t93so6440648yhp.0; Tue, 17 Mar 2015 11:18:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=c3jSrks2owBMUrfKx+Tm0E3MZe/XadOLveiZ4LjOYEo=; b=z799y+9dhd+kJ26fUjqzcSucmlGZtjvx7srqfLUWh3ED9LudaQyojZ9Y6hEOYo0PLo x4Exozq/FKYryZgVLl3pjWZxnwDzk2z9MJA0TlvFXRFbMxlI8ag7Q7JYn5PvXPvSID1Y D7Itute8Mjm4lJiyiMOMuQWEuzutaslzP7/RqVSOR2gWe9jo0phxVuOBClAMLeJV8e7m +/57BsMvtw8OByu1ApP3Exd17NBzjIGDGtzpG7EVDIuPGZSueTFtZiUj0qhSGQAh71Kc bZeZnyw8NEohBS2Hs6qnrwKKX8utqpTZyoKeVFmmEkWiuomJ1xMzDf4CyE1Y7XUGaJ9B qWpQ== MIME-Version: 1.0 X-Received: by 10.170.37.141 with SMTP id 135mr57011939ykf.94.1426616331117; Tue, 17 Mar 2015 11:18:51 -0700 (PDT) Received: by 10.170.60.69 with HTTP; Tue, 17 Mar 2015 11:18:51 -0700 (PDT) In-Reply-To: <55086E2D.9080806@FreeBSD.org> References: <7CBD7758-9472-4A2E-8065-EC6E68EE8DAB@FreeBSD.org> <20150317060310.GA21975@troutmask.apl.washington.edu> <00a001d060d7$0077f100$0167d300$@acm.org> <55086E2D.9080806@FreeBSD.org> Date: Tue, 17 Mar 2015 11:18:51 -0700 Message-ID: Subject: Re: Random number generators From: Mehmet Erol Sanliturk To: Pedro Giffuni Content-Type: text/plain; charset=UTF-8 X-Content-Filtered-By: Mailman/MimeDel 2.1.18-1 Cc: dennis.hamilton@acm.org, freebsd-numerics@freebsd.org X-BeenThere: freebsd-numerics@freebsd.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: "Discussions of high quality implementation of libm functions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 17 Mar 2015 18:18:52 -0000 On Tue, Mar 17, 2015 at 11:10 AM, Pedro Giffuni wrote: > Hi Dennis; > > On 03/17/15 12:22, Dennis E. Hamilton wrote: > >> There is a lot of discussion about qualities of Random Number generators >> on cryptography lists. MT is not a good choice for that, but it might not >> need to be important for other applications. >> >> There has been some recent work, PCG, that has attracted some attention, < >> http://www.pcg-random.org/>. There are good videos explaining what the >> approach is about as well. PCG also has implementations in C. (It is >> under the Apache License 2.0 too: >> for a minimal family and for ones with >> extended capabilities.) >> >> The analysis of what does and doesn't work, and how passing diehard is >> too easy, is also valuable. >> >> If you are serious about crypto grade randomness, libc is probably not >> the answer. Generally, I don't think reliance on a single generator for >> general purpose use and for cryptographic quality is going to work well. >> This is a very context-sensitive situation and addressing specific threat >> models against cryptographic PRGs is a very different matter from wanting >> unpredictable and good quality pseudo-randoms for simulations and other >> purposes. >> > > The pcg-random link seems to be down now but for crypto, we have > arc4random(3) which is pretty good and about to be improved further. > > Pedro. > > _______________________________________________ > > Three of the above links are accessible from here at Izmir , in Turkey . Thank you very much . Mehmet Erol Sanliturk