From owner-svn-src-head@freebsd.org Sat Jul 25 06:20:13 2015 Return-Path: Delivered-To: svn-src-head@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id B63869AA2F8; Sat, 25 Jul 2015 06:20:13 +0000 (UTC) (envelope-from jmg@gold.funkthat.com) Received: from gold.funkthat.com (gate2.funkthat.com [208.87.223.18]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "gold.funkthat.com", Issuer "gold.funkthat.com" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 8C36015A1; Sat, 25 Jul 2015 06:20:13 +0000 (UTC) (envelope-from jmg@gold.funkthat.com) Received: from gold.funkthat.com (localhost [127.0.0.1]) by gold.funkthat.com (8.14.5/8.14.5) with ESMTP id t6P6KCFu002421 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Fri, 24 Jul 2015 23:20:12 -0700 (PDT) (envelope-from jmg@gold.funkthat.com) Received: (from jmg@localhost) by gold.funkthat.com (8.14.5/8.14.5/Submit) id t6P6KCZr002420; Fri, 24 Jul 2015 23:20:12 -0700 (PDT) (envelope-from jmg) Date: Fri, 24 Jul 2015 23:20:12 -0700 From: John-Mark Gurney To: Mark R V Murray Cc: src-committers , svn-src-all@FreeBSD.org, svn-src-head@FreeBSD.org Subject: Re: svn commit: r284959 - in head: . share/man/man4 share/man/man9 sys/conf sys/dev/glxsb sys/dev/hifn sys/dev/random sys/dev/rndtest sys/dev/safe sys/dev/syscons sys/dev/ubsec sys/dev/virtio/random sy... Message-ID: <20150725062012.GT78154@funkthat.com> References: <201506301700.t5UH0jPq001498@svn.freebsd.org> <20150724012519.GE78154@funkthat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Operating-System: FreeBSD 9.1-PRERELEASE amd64 X-PGP-Fingerprint: 54BA 873B 6515 3F10 9E88 9322 9CB1 8F74 6D3F A396 X-Files: The truth is out there X-URL: http://resnet.uoregon.edu/~gurney_j/ X-Resume: http://resnet.uoregon.edu/~gurney_j/resume.html X-TipJar: bitcoin:13Qmb6AeTgQecazTWph4XasEsP7nGRbAPE X-to-the-FBI-CIA-and-NSA: HI! HOW YA DOIN? can i haz chizburger? User-Agent: Mutt/1.5.21 (2010-09-15) X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.7 (gold.funkthat.com [127.0.0.1]); Fri, 24 Jul 2015 23:20:12 -0700 (PDT) X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 25 Jul 2015 06:20:13 -0000 Mark R V Murray wrote this message on Fri, Jul 24, 2015 at 07:59 +0100: > > On 24 Jul 2015, at 02:25, John-Mark Gurney wrote: > > > > I would like to point out that the goal of collecting large amounts > > is starting to fall out of favor, and I happen to agree with the likes > > of djb[1] that we don't need an infinite amount of entropy collected by > > the system. If the attacker can read out our RNG state, then we are > > already screwed due to many other vulns. > > I???m working on a premise of ???tools, not policy???. I???d like there to be > enough harvesting points for the box owner to get the warm fuzzies. > If they choose to use less, fine by me. Except that we should set a sane default policy. Hashing 136 bytes of the mbuf of every ethernet packet isn't a sane default policy. I'm not saying don't have the hooks, but as Scott and others would like, they need to be turned off by default... > > Many of the issues that FreeBSD sees with lack of entropy at start up > > is more of a problem on how systems are installed and provisioned. I > > don't believe that we currently store any entropy from the install > > process, yet this is one of the best places to get it, the user is > > banging on keyboard selecting options, etc. If an image is designed > > to be cloned (vm images or appliance images) we need to have a > > mechanism to ensure that before we start, we get the entropy from > > other sources, be it a hardware RNG or the console. > > Getting an initial entropy bundle for first boot is high up on my > TODO list. :-) Patches welcome! We need the usual /entropy (or > /var/db/entropy/??? or whatever) and crucially we need /boot/entropy > and the correct invocation in /boot/loader.conf. > > > I would like to see us scale back the entropy collection, and replace > > it with something like scan the zone once an hour or something > > similar. Or do something dtrace style, where we nop/jmp the > > collection after we feel that the system has collected enough. > > Most of the current entropy gathering is just about invisible > anyway. I think the above goes too far, but may be a useful way > of enabling/disabling (say) UMA gathering on the fly. Well, just a random proposal to allow both, but these points should be turned off by default, not enabled by default... > > Heck, piping in mic data to /dev/random is a good way to seed the > > rng on many machines. > > Well, sure, but what if you don???t have microphone? I want lots > of choices, in anticipation of only a subset being usable. I'm fine w/ more choices, but we need to make sure we have sane defaults.. -- John-Mark Gurney Voice: +1 415 225 5579 "All that I will do, has been done, All that I have, has not."