From owner-svn-src-all@FreeBSD.ORG Tue Nov 15 07:14:11 2011 Return-Path: Delivered-To: svn-src-all@FreeBSD.ORG Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 2A673106564A; Tue, 15 Nov 2011 07:14:11 +0000 (UTC) (envelope-from ache@vniz.net) Received: from vniz.net (vniz.net [194.87.13.69]) by mx1.freebsd.org (Postfix) with ESMTP id 9EAAB8FC15; Tue, 15 Nov 2011 07:14:10 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by vniz.net (8.14.5/8.14.5) with ESMTP id pAF7E8g6090331; Tue, 15 Nov 2011 11:14:09 +0400 (MSK) (envelope-from ache@vniz.net) Received: (from ache@localhost) by localhost (8.14.5/8.14.5/Submit) id pAF7E8Yr090330; Tue, 15 Nov 2011 11:14:08 +0400 (MSK) (envelope-from ache) Date: Tue, 15 Nov 2011 11:14:08 +0400 From: Andrey Chernov To: David Schultz Message-ID: <20111115071407.GB86944@vniz.net> Mail-Followup-To: Andrey Chernov , David Schultz , src-committers@FreeBSD.ORG, svn-src-all@FreeBSD.ORG, svn-src-head@FreeBSD.ORG References: <201111150549.pAF5nOu8083029@svn.freebsd.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <201111150549.pAF5nOu8083029@svn.freebsd.org> User-Agent: Mutt/1.5.21 (2010-09-15) Cc: svn-src-head@FreeBSD.ORG, svn-src-all@FreeBSD.ORG, src-committers@FreeBSD.ORG Subject: Re: svn commit: r227520 - head/lib/libc/gen X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 15 Nov 2011 07:14:11 -0000 On Tue, Nov 15, 2011 at 05:49:24AM +0000, David Schultz wrote: > Author: das > Date: Tue Nov 15 05:49:24 2011 > New Revision: 227520 > URL: http://svn.freebsd.org/changeset/base/227520 > > Log: > Further reduce diffs with OpenBSD's arc4random. The main functional > change here is to ensure that when a process forks after arc4random > is seeded, the parent and child don't observe the same random sequence. > OpenBSD's fix introduces some additional overhead in the form of a > getpid() call. This could be improved upon, e.g., by setting a flag > in fork(), if it proves to be a problem. > > This was discussed with secteam (simon, csjp, rwatson) in 2008, shortly > prior to my going out of town and forgetting all about it. The conclusion > was that the problem with forks is worrisome, but it doesn't appear to > have introduced an actual vulnerability for any known programs. > > The only significant remaining difference between our arc4random and > OpenBSD's is in how we seed the generator in arc4_stir(). Thanx for taking that! -- http://ache.vniz.net/