From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from goalie.tycho.ncsc.mil (goalie [144.51.3.250]) by tarius.tycho.ncsc.mil (8.13.1/8.13.1) with ESMTP id nB14MCd7018400 for ; Mon, 30 Nov 2009 23:22:12 -0500 Received: from mailhub248.itcs.purdue.edu (localhost [127.0.0.1]) by msux-gh1-uea01.nsa.gov (8.12.10/8.12.10) with ESMTP id nB14L5FU015819 for ; Tue, 1 Dec 2009 04:21:05 GMT Message-ID: <4B14934F.9050401@cs.purdue.edu> Date: Mon, 30 Nov 2009 22:53:51 -0500 From: Jacques Thomas MIME-Version: 1.0 To: KaiGai Kohei CC: SE Linux , method@manicmethod.com Subject: Re: Type boundaries: questions on the semantics / is the enforcement correct ? References: <4AF71B05.8030707@cs.purdue.edu> <4B035FA4.6080605@ak.jp.nec.com> <4B056D3D.2050303@cs.purdue.edu> <4B1411B5.5050406@cs.purdue.edu> <4B146B17.50706@ak.jp.nec.com> In-Reply-To: <4B146B17.50706@ak.jp.nec.com> Content-Type: text/plain; charset=ISO-2022-JP Sender: owner-selinux@tycho.nsa.gov List-Id: selinux@tycho.nsa.gov KaiGai Kohei wrote: >>>> I also think we have one other a rough option. >>>> It simply applies type boundaries on only sources to restrict its privileges, >>>> and it does not apply any restrictions on target types. >>>> >>>> >>>> >>> Unless there is a clear use for bounds on targets, I would favor this >>> option. (The "rough" one :-) ) >>> I see mostly room for confusion with the bounds on target types, because >>> of the contravariance issue. >>> >>> >> I can write and submit a patch along these lines. The patch is >> straightforward: I just have to remove the "dead" code. >> > > Note that libsepol has an option which test type-boundary violations > in usermode just before policy load. > Also check check_avtab_hierarchy_callback() in libsepol/src/hierarchy.c. > (It is called when ) > > Historically, this code delivered from hierarchy namespace support by > Joshua Brindle. I'd like to ask him what about this change. > > MEMO: The hierarchy namespace support implicitly set up type-boundary > on a couple of types. For example, if we defined httpd_t.cgi type, > it is implicitly bounded by httpd_t type without TYPEBOUNDS. > > I also have not seen any case example which restrict target types by > the hierarchy namespace support. So, it seems to me we have no matter > to remove the "dead" code. > > Joshua, what's your opinion? > > > >> However, could someone please indicate me how I am supposed to test the >> patch ? In other words, is there a standardized testing procedure that I >> am unaware of ? >> > > http://ltp.sourceforge.net/ > > It also contains SELinux testcases including type boundary, but it also > does not contains a case of type boundary on target types. > Kaigai, thank you for you detailed answer. Joshua, I am waiting for your opinion. Thank you both, Jacques -- This message was distributed to subscribers of the selinux mailing list. If you no longer wish to subscribe, send mail to majordomo@tycho.nsa.gov with the words "unsubscribe selinux" without quotes as the message.