From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: Jimmy Yuen Ho Wong Newsgroups: gmane.emacs.devel Subject: Re: A couple of questions and concerns about Emacs network security Date: Mon, 9 Jul 2018 18:09:44 +0100 Message-ID: References: <83o9g2uhju.fsf@gnu.org> <20180705115826.73c1d95e@jabberwock.cb.piermont.com> <878t6lom8g.fsf@mouse.gnus.org> <87pnzxn4kw.fsf@mouse.gnus.org> <87fu0tmxfs.fsf@mouse.gnus.org> <83va9pha36.fsf@gnu.org> <83tvp9h9dv.fsf@gnu.org> <87y3ellggt.fsf@mouse.gnus.org> <83sh4th84d.fsf@gnu.org> <87fu0tle7f.fsf@mouse.gnus.org> <83k1q4gx57.fsf@gnu.org> NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" X-Trace: blaine.gmane.org 1531156156 15757 195.159.176.226 (9 Jul 2018 17:09:16 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Mon, 9 Jul 2018 17:09:16 +0000 (UTC) Cc: Lars Ingebrigtsen , Emacs-Devel devel To: Eli Zaretskii Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Mon Jul 09 19:09:12 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 1fcZew-0003wy-W7 for ged-emacs-devel@m.gmane.org; Mon, 09 Jul 2018 19:09:11 +0200 Original-Received: from localhost ([::1]:43482 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fcZh2-0006rX-Gl for ged-emacs-devel@m.gmane.org; Mon, 09 Jul 2018 13:11:20 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:37470) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fcZfq-0006iE-Sz for emacs-devel@gnu.org; Mon, 09 Jul 2018 13:10:12 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fcZfn-0007fO-1p for emacs-devel@gnu.org; Mon, 09 Jul 2018 13:10:06 -0400 Original-Received: from mail-io0-x22b.google.com ([2607:f8b0:4001:c06::22b]:37990) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1fcZfi-0007eH-PG; Mon, 09 Jul 2018 13:09:58 -0400 Original-Received: by mail-io0-x22b.google.com with SMTP id v26-v6so17718030iog.5; Mon, 09 Jul 2018 10:09:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=YKrQHS9lPdRMkzSec58mftMZieFaVDkAs45GVqrZySM=; b=Bi7cGrlgD8DVTj0u3+8txMG53OVSX1vrFeEaYirmtgyXRJxcp8cn4zoUdUM7WJANDn 4t7jZPxZriOrBN/YUTV2xbmNcpBKUIaBePVPvfjfzovLF4qiVi9aoAkrDijBL6VFSVuj 9132r59e0RTbEJwuq98C7fzkqMOxB8qqqjw3CAI9nE6Gn9zJvXaRV3DFzOfzZozeWhVA nNqDEQOR9tJxd/FhVxXhfEHvQe1QqIK6NxwaxjpZGYL9oN+jTyZlW8rOFqmy2acqFbEu JIzzD4b8bkNHDD45/zXJY6N7eY3ljv1ULdJN7XsCrlcos+NSc4rLt7q1wAgmNIh3bXGE Q3rA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=YKrQHS9lPdRMkzSec58mftMZieFaVDkAs45GVqrZySM=; b=QVzvGwUnYyVFEXvsxFc4NYJW+6wBRbmniZWLJAoyrU4czMV9AGVzjnfRljUolRoENV WoPH/zPz9WJNJkqdBzmjwQJnWVQ401doN2VFpBkzfRvWUMPgbuOfrn6hJO7ADJLVMo5C 0GP5mumqFaoLwRI2PHGRJts0p2Qhy8Hm0Bm81BlE2evNCGctRKgNloZvhBjhpm6jlWdW wogXDuNARQuReufrZa4KBsdglARaUUR7cH2qrXJTP3kNklEo4pgVt4bkbBddSN42VScZ GDz1VmcCmAhqB6GamDC2bZme/ULTh/d3oqQoykdPoVSbSkjctKW0y3u0KoXdhJfbz9hY Zz9g== X-Gm-Message-State: APt69E1ZVVSRRup1RSpwFmuHmNC/nmerzi8V06+U1MCQZ6xqJuPM/0da +g4J4YdZgWOqyRWNzu2godxBWy+ALn6l9GJZy1Yi0A== X-Google-Smtp-Source: AAOMgpdt7pLSqxHq/bD6MEvGlYlKHbofcSQcqqtinK3AE2B6NS9iZksae/jY+kvwYYknMz+SJ14NMlNxn3Qq762XSsE= X-Received: by 2002:a6b:2092:: with SMTP id g140-v6mr17354397iog.167.1531156197130; Mon, 09 Jul 2018 10:09:57 -0700 (PDT) In-Reply-To: <83k1q4gx57.fsf@gnu.org> X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 2607:f8b0:4001:c06::22b 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:227161 Archived-At: On Mon, Jul 9, 2018 at 6:02 PM Eli Zaretskii wrote: > > > From: Lars Ingebrigtsen > > Cc: wyuenho@gmail.com, emacs-devel@gnu.org > > Date: Sun, 08 Jul 2018 21:28:20 +0200 > > > > Eli Zaretskii writes: > > > > >> Users aren't supposed to care about that variable, anyway, since the NSM > > >> warns about less than 1024 bits... > > > > > > Yes, but what if GnuTLS bumps the default to more than that? And even > > > if not, I think I might like to know how far below 1024 I'm going to > > > be if I allow the connection. > > > > The NSM will say explicitly how many bits the DH exchange is using. Try > > this one with `M-x eww' > > > > https://dh480.badssl.com/ > > > > and you should get the warning. > > The warning says > > The Diffie-Hellman prime bits (480) used for this connection to > dh480.badssl.com:443 is less than what is considered safe (1024) > > So it doesn't show the 1008 value. What did I miss? Nothing. The server you are connecting will only give you a 480-bit prime. Since your Emacs is still using 256 `gnutls-min-prime-bit`, GnuTLS lowered the lower bound from 1008 to 256, and then negotiate a bit length as high as the server can go. What you see is expected.