From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: Stephen Berman Newsgroups: gmane.emacs.devel Subject: Re: A couple of questions and concerns about Emacs network security Date: Fri, 06 Jul 2018 11:45:17 +0200 Message-ID: <87wou8itoy.fsf@gmx.net> References: <83po0iuhs7.fsf@gnu.org> <20180705113320.17e6b8ee@jabberwock.cb.piermont.com> <83po01mrvh.fsf@gnu.org> <87po00ahg9.fsf@gmail.com> <83601sn3yu.fsf@gnu.org> NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-Trace: blaine.gmane.org 1530870252 24347 195.159.176.226 (6 Jul 2018 09:44:12 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Fri, 6 Jul 2018 09:44:12 +0000 (UTC) User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.0.50 (gnu/linux) Cc: Robert Pluim , emacs-devel@gnu.org To: Eli Zaretskii Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Fri Jul 06 11:44:07 2018 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1fbNHa-0006CI-VH for ged-emacs-devel@m.gmane.org; Fri, 06 Jul 2018 11:44:07 +0200 Original-Received: from localhost ([::1]:56689 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fbNJg-0004xD-Br for ged-emacs-devel@m.gmane.org; Fri, 06 Jul 2018 05:46:16 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:44336) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fbNIx-0004wl-5t for emacs-devel@gnu.org; Fri, 06 Jul 2018 05:45:34 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fbNIt-0000Gc-68 for emacs-devel@gnu.org; Fri, 06 Jul 2018 05:45:31 -0400 Original-Received: from mout.gmx.net ([212.227.15.19]:57109) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1fbNIn-0008Dq-Tn; Fri, 06 Jul 2018 05:45:22 -0400 Original-Received: from rosalinde ([178.1.122.251]) by mail.gmx.com (mrgmx003 [212.227.17.190]) with ESMTPSA (Nemesis) id 0MfEZG-1flri1019e-00OmXr; Fri, 06 Jul 2018 11:45:19 +0200 In-Reply-To: <83601sn3yu.fsf@gnu.org> (Eli Zaretskii's message of "Fri, 06 Jul 2018 11:49:45 +0300") X-Provags-ID: V03:K1:SDuCc1USoFGkg/5VKFfU0NxTboP18lX6gYWR/DrH8ArBeFzEUJE aze1gkqZzx3AsJuYlgj5oGQk1x/P5SW679sd6SCcuNnHyFRa+e4XrCnThbNgo13TFgw3fVS vZKIsKLm1JsXOQsAZu6GnjHCJU6TcKifgfhE2/sBSQagSNie7MV/JTqqw/BTJMtriAZTHyb rZL98Hksc6LNNIQ4/i27Q== X-UI-Out-Filterresults: notjunk:1;V01:K0:adGt2LuP3JI=:gK8ru/RX7xaVjor/44mZis O81kuFKxB2r0n9VPKKexZ6TS+E14j+0VDQZlgAqdZBpcdh+/NKBiJdBjHikzlNcs7asPSS3te NiGyaTgXPP4KfAfsdFWahmekVeqpPeZkcZHMPtwdngJSbJt6q3p8Kdk0X1UCmdW4ky7yLzD/z oP7tgkFQ4YrgBEGLPFsXCKc9laOaDTQ4HH5vD2UPOXw9mi3YkzzrInXoxIStN65qNbj+dN1cN QlY0u5YRvxcnLAl1jWz4Wfd6JFJF8aJj9xNHf0DlgJg4kx0eVRY/1YlgOsbacOHwedhU1qGJC 1u90FmqumkymVkY/PhFjd/rCjjjkg22axbvbL7ksKMxkpwqpKtSvc5VjfmOf4S0cPZCDwTYTG nnre7pn1SIKHbSz+dPx5pTox0jfl92Q20VtKDbZWaYyVM8w6U5H1gLqkAIbSwEJ8QGfUy+zJf NRy5sMCsrOjh1mXfK+QuI3zTPPna+g6ZpBif8aRnqnXw6Q+NOa9rN4BKPjBrEDjrrSRHPvlow cGDd1kt6LORNfAS4pGP9lm/U3bIN802T/ICAgcYo+XwimJpO5ksQrnyqF6BDHLfSjNdlydlbX xpDG/YL6BCaATUYlISki3SIpDXl/AF6L4SMd6Lj7GvHHSKZV7B3v/y1P1lntYQR4bD/nosj1w Xs6b6JfpI3xjaRnYHmdIBi25GA6BKJ/i74ogpw4NJp0/V3ShOtAs7S/y+l6er+JS/8aWwNQIi IH6RBTyIf6i535QYXvqvqSf5OslHwtNvZuCNNVRc9w5zUWi1jR186C8CZyB0HNk0aKsmG+b1 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 212.227.15.19 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Original-Sender: "Emacs-devel" Xref: news.gmane.org gmane.emacs.devel:226994 Archived-At: On Fri, 06 Jul 2018 11:49:45 +0300 Eli Zaretskii wrote: >> From: Robert Pluim >> Cc: "Perry E. Metzger" , larsi@gnus.org, >> eggert@cs.ucla.edu, emacs-devel@gnu.org, npostavs@gmail.com, >> wyuenho@gmail.com >> Date: Fri, 06 Jul 2018 10:36:54 +0200 >>=20 >> > Anyway, it seems you completely miss my point: I didn't say that we >> > shouldn't increase the number of bits, just that we shouldn't do that >> > on the release branch, unless we are willing to delay Emacs 26.2 >> > significantly. >>=20 >> FWIW, I=CA=BCve had gnutls-min-prime-bits set to 1024 since 2014-11-25, = and >> have seen no adverse effects from it, so I don=CA=BCt think the risk is >> that great. > > Thanks for the data point. > > Unfortunately, our experience is that use patterns vary widely between > different Emacs users, and so problem-free experience of a single > individual, or even several people, is not enough to be sure there are > no significant issues. And TLS secured connections are central to > many Emacs features. > > Emacs 26.2 is supposed to have fewer significant bugs than Emacs 26.1, > so we must be careful if we make changes that could bring new > problems. I think in this case it is likely that the higher setting has in effect already undergone prolongued testing, since there is reason to think it has been used by many, perhaps most, Emacs users for a long time, in my case since reading this posting: From: "Herbert J. Skuhra" Subject: Re: gnutls.c warning Newsgroups: gmane.emacs.gnus.general To: david@adboyd.com (J. David Boyd) Cc: ding@gnus.org Date: Tue, 25 Jun 2013 23:38:14 +0200 (5 years, 1 week, 3 days ago) =20=20 On Tue, 25 Jun 2013 15:07:08 -0400 david@adboyd.com (J. David Boyd) wrote: =20=20 >=20 > I keep getting this warning, and can't find any way to turn it off. >=20 > gnutls.c: [1] Note that the security level of the Diffie-Hellman key > exchange has been lowered to 256 bits and this may allow decryption > of the session data >=20=20 > Is there some setting to say ok, I understand, quit nagging me? =20=20 After setting gnutls-min-prime-bits to 1024 I no longer get this warning. Given this, it seems reasonable to conclude that most Emacs users who continue to use the current default setting are aware of the risk, and those who have changed it haven't experienced a problem worth reporting. Therefore, changing the default at this time is not likely to cause a problem for most long-time users, and will be safer for all new users, and most likely unproblematic for them (and if it is a problem, then they will know the trade-off). Steve Berman