From owner-freebsd-numerics@FreeBSD.ORG Tue Mar 17 18:44:26 2015 Return-Path: Delivered-To: freebsd-numerics@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id DDDC8654 for ; Tue, 17 Mar 2015 18:44:26 +0000 (UTC) Received: from nm16.bullet.mail.bf1.yahoo.com (nm16.bullet.mail.bf1.yahoo.com [98.139.212.175]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 8F2D1868 for ; Tue, 17 Mar 2015 18:44:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yahoo.com; s=s2048; t=1426617545; bh=KzuLTdQSCB5Ea78B4DynnOHFeZWmCVcgceDcO81okwM=; h=Date:From:To:CC:Subject:References:In-Reply-To:From:Subject; b=kTuDMVAWgzg97n4VD+DT74hPMMhlanCdTZAPxAt+IJavDKOStVUT0CORVDLV4qW9dYb8HERxTEsXZwB5kghHy3MGLybphPe2ZvcT8gsp8gPHuniv+RLv1XlNr7CXusGxkBIFvTYa9L74x3B/UK2pGfONqJkqL+zC2Z9uU0wAqiojiLKwwvH1yoZ7D3XukP6ZaQ1HYS9YVEbZfYvLGcrcm5Mg97ga49KcM5DGuLiSkWONbgrI/BB+W3sSJxfFk3jHM3mnir6ZsJuTc2/d/kOjCRYJ7yJWBnXkvEXN4sdFmsTTMJ6BwBFHenTHn1dEMSaeoJ5yMLbIAGJ2AA5StkBlfA== Received: from [98.139.170.182] by nm16.bullet.mail.bf1.yahoo.com with NNFMP; 17 Mar 2015 18:39:05 -0000 Received: from [98.139.211.205] by tm25.bullet.mail.bf1.yahoo.com with NNFMP; 17 Mar 2015 18:39:05 -0000 Received: from [127.0.0.1] by smtp214.mail.bf1.yahoo.com with NNFMP; 17 Mar 2015 18:39:05 -0000 X-Yahoo-Newman-Id: 546457.53950.bm@smtp214.mail.bf1.yahoo.com X-Yahoo-Newman-Property: ymail-3 X-YMail-OSG: k3ItqBkVM1k9.IgL47AovhHAqmEZ4tqIBucHyLYgKITb_JC CuvV7tScE_L9v2EZimGDMJexBT7J.Jjw1zzykTMTt1pAfP0TCQCUbO_irEAp wYJ1FXr85TmN_ExtA6yLl7Kg0ldkmkB2v_EYHQ21Swo5TD4WNDwp6zhfXpuL KCCWJbrdFOVxOQcKgORd1sQ4D_HZab_RCW58sc9PEDK.L8zEmOHLRrev7krj 81vddC0zVIjAfIyiEJYAvMgKZ7Wcwt8eKl2auweHl.P6poFTbERKMLaK68go dYIGOcxzsWyLOkMn3lVvy2pSUyk_rC35YfZ.cKL23IGHH8CQgQx4NtFjtjW4 x0wZK_t8nyWO0rVAnBdq33KfHKw3Wb.YRmn1MhSUAKrpUJbtLEHq0p4F27k0 a4ToSNrA5SQw0yRbVzNdX5VKyQXGgFHqSp.8ADMy470hZAXdG5.kL33GDQBi cAP695xY_5U961ppfxwBrIPkRIuC_YSoYikAGjYvp0vnoODYqYOdzUrpay3y rAG_BUqeHBPWJaFSiaqghxboLCCpA.wjo0gO_czwkUkX.DnYtHK_DRjk6rZD CRMtmuWY9HvWVis.wSIaE8bi6VBmri4iPeFWbc2gjJ4Y.sW8SZhb7ix3K0WZ Qk_7XeXQX0bqiHBTtjrpAiYzXbTyd.EvbpQH_6Q-- X-Yahoo-SMTP: xcjD0guswBAZaPPIbxpWwLcp9Unf Message-ID: <550874DE.3060700@FreeBSD.org> Date: Tue, 17 Mar 2015 13:39:26 -0500 From: Pedro Giffuni User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:31.0) Gecko/20100101 Thunderbird/31.4.0 MIME-Version: 1.0 To: Mehmet Erol Sanliturk Subject: Re: Random number generators References: <7CBD7758-9472-4A2E-8065-EC6E68EE8DAB@FreeBSD.org> <20150317060310.GA21975@troutmask.apl.washington.edu> <00a001d060d7$0077f100$0167d300$@acm.org> <55086E2D.9080806@FreeBSD.org> In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit 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 18:44:27 -0000 Hi; On 03/17/15 13:18, Mehmet Erol Sanliturk wrote: > > > 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, . 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 . > It just came up here. It looks like PCG compares favorably with ChaCha20, but this is PCG's page and the comparison is not very clear ("Secure" vs "Challenging"?) It may be worth considering though. Pedro.