From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <4A3BD987.70602@manicmethod.com> Date: Fri, 19 Jun 2009 14:31:35 -0400 From: Joshua Brindle MIME-Version: 1.0 To: Daniel J Walsh CC: SE Linux , Chad Sellers , Stephen Smalley Subject: Re: This patch add seusers support to SELinux References: <4A11A6EE.3070903@redhat.com> <4A3A4366.3010606@manicmethod.com> <4A3A45B0.4070803@manicmethod.com> <4A3A97B0.6030407@redhat.com> <4A3AA03E.4010208@manicmethod.com> <4A3B6110.8010308@redhat.com> <4A3BA9DC.2060406@manicmethod.com> <4A3BACE9.6000403@redhat.com> <4A3BD53A.5050908@manicmethod.com> <4A3BD7DB.9030106@redhat.com> <4A3BD88E.5010103@manicmethod.com> <4A3BD944.7090608@redhat.com> In-Reply-To: <4A3BD944.7090608@redhat.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Sender: owner-selinux@tycho.nsa.gov List-Id: selinux@tycho.nsa.gov Daniel J Walsh wrote: > On 06/19/2009 02:27 PM, Joshua Brindle wrote: >> Daniel J Walsh wrote: >>> On 06/19/2009 02:13 PM, Joshua Brindle wrote: >>>> Daniel J Walsh wrote: >>>>> On 06/19/2009 11:08 AM, Joshua Brindle wrote: >>>>>> Daniel J Walsh wrote: >>>>>>> On 06/18/2009 04:14 PM, Joshua Brindle wrote: >>>>>>>> Daniel J Walsh wrote: >>>>>>>>> On 06/18/2009 09:48 AM, Joshua Brindle wrote: >>>>>>>>>> Joshua Brindle wrote: >>>>>>>>>>> Daniel J Walsh wrote: >>>>>>>>>>>> The idea here is to break the seusers file up into lots of >>>>>>>>>>>> little >>>>>>>>>>>> seusers file that can be user specific, also adds the service >>>>>>>>>>>> field to >>>>>>>>>>>> be used by tools like pam_selinux to choose which is the >>>>>>>>>>>> correct >>>>>>>>>>>> context >>>>>>>>>>>> to log a user in as. >>>>>>>>>>>> >>>>>>>>>>>> Patch was added to facilitate IPA handing out SELinux content >>>>>>>>>>>> for >>>>>>>>>>>> selection of roles at login. >>>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> This patch does not affect the behavior of getseuserbyname(), >>>>>>>>>>> how is >>>>>>>>>>> this expected to work with existing applications? >>>>>>>>>>> >>>>>>>>> I think it only affects pam_selinux. >>>>>>>> >>>>>>>> The function name is very confusing if its only used for >>>>>>>> pam_selinux, >>>>>>>> I'd like it renamed but seeing that pam_selinux is already deployed >>>>>>>> with >>>>>>>> it I suppose that isn't an option. >>>>>>>> >>>>>>>> Signed-off-by: Joshua Brindle >>>>>>>> >>>>>>>>>> >>>>>>>>>> Also, what is the format of this file? What should service be to >>>>>>>>>> test >>>>>>>>>> this on F11? >>>>>>>>>> >>>>>>> It is not only for pam_selinux, but that is currently the only user. >>>>>>> >>>>>>> Really all this function does is add a second variable when >>>>>>> selecting a >>>>>>> users default context. service is just a string that the caller can >>>>>>> specify. It just allows you to change the default context you would >>>>>>> get >>>>>>> on entry to the system. So I guess you could get use similar >>>>>>> calls to >>>>>>> get different context depending on whether or not you are on the >>>>>>> console. Imagine a dbus service which would run with one context if >>>>>>> you >>>>>>> we logged onto the console versus a different context if you were >>>>>>> logged >>>>>>> in via ssh. >>>>>>> >>>>>> >>>>>> On looking at this further, I don't like the format of the file >>>>>> either, >>>>>> why did you choose to make it use colons and not tolerate spaces? >>>>>> First >>>>>> when I tried root: staff_u: s0 it logged me in as system_u and then >>>>>> when >>>>>> I tried root:staff_u:s0 I got logged in correctly. This is a little >>>>>> fragile to expect editing by users and getting unexpectedly logged >>>>>> in as >>>>>> system_u. >>>>>> >>>>>> -- >>>>> The : separated list matches seusers and /etc/passwd so I think it >>>>> makes >>>>> sense. THe file should require all three fields, that is a bug. >>>>> >>>> >>>> Ok, This is also yet-another-way to map users in SELinux, and its >>>> different from everything else. We use contexts to map other >>>> services to >>>> users ala contexts/default_contexts and contexts/users/*. Why should >>>> this be any different? If there are multiple sshd's running, eg., on a >>>> high nic and low nic then they'd need to map contexts via context >>>> rather >>>> than "service" name. >>>> >>>> I still haven't figured out what this is solving. >>>> >>>> -- >>>> 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. >>> >>> >>> I want to say that on these 50 machines dwalsh logs in via ssh as >>> guest_t:SystemLow >>> >>> If he logs in via the console he logs in as staff_t:SystemLow-SystemHigh >>> >>> Now distribute this out to hundreds of thousands of machines. >>> >> >> How is this different from distributing the contexts/users/dwalsh file? >> >> [root@localhost contexts]# cat users/dwalsh >> system_r:local_login_t:s0 staff_r:staff_t:s0 >> system_r:sshd_t:s0 guest_r:guest_t:s0 >> >> > That is an SELinux users file not a UID users file > > The dwalsh user does not exist. > Oops, you are right. Will this cause confusion if semanage login -l doesn't read this file and report its contents as well? Are you sure we should be using the service name and not the context of the service, for the reason I pointed out above? -- 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.