From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mp2 ([2001:41d0:2:4a6f::]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) by ms11 with LMTPS id ojxTFQhVWV8XDAAA0tVLHw (envelope-from ) for ; Wed, 09 Sep 2020 22:19:52 +0000 Received: from aspmx1.migadu.com ([2001:41d0:2:4a6f::]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) by mp2 with LMTPS id +GLkEAhVWV9jLwAAB5/wlQ (envelope-from ) for ; Wed, 09 Sep 2020 22:19:52 +0000 Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by aspmx1.migadu.com (Postfix) with ESMTPS id 9274F940215 for ; Wed, 9 Sep 2020 22:19:51 +0000 (UTC) Received: from localhost ([::1]:43352 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kG8RS-0007l2-5j for larch@yhetil.org; Wed, 09 Sep 2020 18:19:50 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:52806) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kG8RJ-0007kW-JP for guix-devel@gnu.org; Wed, 09 Sep 2020 18:19:41 -0400 Received: from dustycloud.org ([50.116.34.160]:38766) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kG8RH-0001up-Iu for guix-devel@gnu.org; Wed, 09 Sep 2020 18:19:41 -0400 Received: from twig (localhost [127.0.0.1]) by dustycloud.org (Postfix) with ESMTPS id 2F0822662F; Wed, 9 Sep 2020 18:19:38 -0400 (EDT) References: <877dtj753p.fsf@gmail.com> <871rja3hdv.fsf@dustycloud.org> User-agent: mu4e 1.4.12; emacs 26.3 From: Christopher Lemmer Webber To: =?utf-8?Q?G=C3=A1bor?= Boskovits Subject: Re: Setuid programs In-reply-to: Date: Wed, 09 Sep 2020 18:19:34 -0400 Message-ID: <87eena1tl5.fsf@dustycloud.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Received-SPF: pass client-ip=50.116.34.160; envelope-from=cwebber@dustycloud.org; helo=dustycloud.org X-detected-operating-system: by eggs.gnu.org: First seen = 2020/09/09 18:19:38 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: guix-devel@gnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: "Development of GNU Guix and the GNU System distribution." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Guix-devel , Maxim Cournoyer Errors-To: guix-devel-bounces+larch=yhetil.org@gnu.org Sender: "Guix-devel" X-Scanner: scn0 Authentication-Results: aspmx1.migadu.com; dkim=none; dmarc=none; spf=pass (aspmx1.migadu.com: domain of guix-devel-bounces@gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=guix-devel-bounces@gnu.org X-Spam-Score: -1.01 X-TUID: 0znbZNBN7qDi G=C3=A1bor Boskovits writes: > Hello, > > Christopher Lemmer Webber ezt =C3=ADrta (id=C5= =91pont: > 2020. szept. 9., Sze, 21:00): >> >> Maxim Cournoyer writes: >> >> > Hello Gabor! >> > >> > G=C3=A1bor Boskovits writes: >> > >> >> Hello guix, >> >> >> >> I would like to propose an extension to how setuid programs are >> >> currently handled. The last time I checked it could only do setuid and >> >> setgid root. Some services, such as postfix need a more fine grained >> >> setuid setup. I would propose a record type, such as: >> >> (setuid >> >> (program setuid-program) >> >> (setuid setuid-setuid) >> >> (setgid setuid-setgid) >> >> (user setuid-user) >> >> (group setuid-group)) >> >> >> >> So that there is more fine grained control. >> >> >> >> I would also propose to move this to the services framework, so that >> >> services could extend this field on demand. >> >> >> >> Wdyt? >> > >> > This sounds great! I also encountered such limitation and tried to >> > fixing it in https://issues.guix.info/41763, with some success (and an >> > unresolved limitation pointed by Chriistopher) but I agree that using a >> > record makes more sense and is more future proof. >> > >> > Maxim >> >> I'm eager to use Postfix on Guix (maybe it's me, but I just can't make >> sense of the weird DSL that opensmtpd uses) so I guess if that's what's >> necessary it already makes it a good idea. >> >> However I don't fully understand the syntax of what you proposed. Let's >> see if I can guess with a fake entry >> >> #~(setuid >> ;; The program to run, from the shady package >> (program (string-append #$shady "/bin/scaryfoo") >> ;; Would this be a boolean? If so should it be `setuid?` > yes, this should be a bool, studi? looks good to me. >> (setuid setuid-setuid) >> ;; Likewise? >> (setgid setuid-setgid) > yes, the same thing applies here. >> ;; Presumably the use we want to set this to >> (user setuid-user) > yes, this should just be the uid of the owner >> ;; Presumably the group we want to se this to > this should be the gid. >> (group setuid-group)) >> >> ... right? >> >> I guess this could be done in a backwards compatible way; >> %setuid-programs could either evaluate to strings or records, so the >> "simpler" version can remain an option? > Yes, it can be done this way. Actually I had a bit more general > solution in mind, > I feel there should be service to install a file from a store to a > given place, and with all the access control available, > like acl-s, if supported. And then provide the whole setuid thing as a > backwards compatibility layer, somehow like you described. > For now I guess creating this record type and implementing the > extended setuid functionality would be a good first step. A service seems like a really good idea to me in that it feels the most composable with how Guix currently approaches things.