From owner-freebsd-current@FreeBSD.ORG Fri Mar 7 18:48:12 2014 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id BFC1249A for ; Fri, 7 Mar 2014 18:48:12 +0000 (UTC) Received: from mail-we0-x229.google.com (mail-we0-x229.google.com [IPv6:2a00:1450:400c:c03::229]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id 57AD195 for ; Fri, 7 Mar 2014 18:48:12 +0000 (UTC) Received: by mail-we0-f169.google.com with SMTP id w62so5514803wes.28 for ; Fri, 07 Mar 2014 10:48:10 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=googlemail.com; s=20120113; h=date:from:to:subject:message-id:in-reply-to:references:mime-version :content-type:content-transfer-encoding; bh=4V7g56t862z2mSF7PJ6Psk6YeT1WEBIzsfp0vdqk/zo=; b=lDGp+yA5ixbfxOHyQiJ7Y1/dgqdFLfkMovoCCghlbv0iqdCVvJVUrmJbIVCyHOagOa bGfCmwN75k0xMzct8sn+rnaaUPIBADyN4xbwWW1ktggiRop/2sZ8WVSbKn57rFcFMyYf 2DEQlqx2hmujhlvsTNyflUDaWK4cYtIA+FSg4fQnRyf82hSFTtLrq3r8kKUxKylK+j2L D9Z3ITWNcF3ZXznty7DrrkM2T/YuZLFEtP5lPb/8O7/CQiunpIrlke+99jPl6atT7uej DpgPwA9zDYMni8dUrpL3hEOydKhnZKcAdxxy7JVV5PTLaW5PGbh/mM8iZGcLE+cLPsHA jJvA== X-Received: by 10.194.86.233 with SMTP id s9mr21246925wjz.44.1394218090761; Fri, 07 Mar 2014 10:48:10 -0800 (PST) Received: from gumby.homeunix.com ([94.195.197.124]) by mx.google.com with ESMTPSA id hy8sm13523303wjb.2.2014.03.07.10.48.08 for (version=SSLv3 cipher=RC4-SHA bits=128/128); Fri, 07 Mar 2014 10:48:09 -0800 (PST) Date: Fri, 7 Mar 2014 18:48:06 +0000 From: RW To: freebsd-current@freebsd.org Subject: Re: Feature Proposal: Transparent upgrade of crypt() algorithms Message-ID: <20140307184806.1a43cfc2@gumby.homeunix.com> In-Reply-To: <201403070913.30359.jhb@freebsd.org> References: <2167732.JmQmEPMV2N@desktop.reztek> <201403070913.30359.jhb@freebsd.org> X-Mailer: Claws Mail 3.9.3 (GTK+ 2.24.22; amd64-portbld-freebsd10.0) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.17 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 07 Mar 2014 18:48:12 -0000 On Fri, 7 Mar 2014 09:13:30 -0500 John Baldwin wrote: > I am assuming that an > administrator wants the transparent upgrade (which I think is useful) > because they are assuming that the hash algorithm is compromised or > inferior. I'd expect it to be done well in advance of that to give plenty of time for the transition. We are talking about brute force attacks and GPU development is relatively predicable. And lets not lose sight of the fact that we are only talking about limited mitigation after an attacker has gained root access, not front-line security. > I suppose if you really were paranoid about the hash what you would > want is an ability to set an expiration time on the hash algo itself > where authentication using that hash always fails after the > expiration time. Whenever I've been required to change passwords it's always been imposed immediately after a login. Just locking-out an account sounds very heavy-handed to me. It seems like it would be trivial to extract a list of accounts using the old-style hashes from master.passwd - at least that way you can send them an email.