From: guido@trentalancia.net (Guido Trentalancia) Date: Fri, 21 Apr 2017 15:47:35 +0200 Subject: [refpolicy] [PATCH] login related stuff take 2 In-Reply-To: <20170421134201.GC2335@julius> References: <20170421091025.kwn5wmevhmoyidj3@athena.coker.com.au> <201704212238.06684.russell@coker.com.au> <20170421124246.GA2335@julius> <20170421124848.GB2335@julius> <81B0E11D-B5E5-41C6-BFF8-91699B40E271@trentalancia.net> <20170421134201.GC2335@julius> Message-ID: <16C6159B-E15B-44E5-AFEC-2FB1FFBA339C@trentalancia.net> To: refpolicy@oss.tresys.com List-Id: refpolicy.oss.tresys.com I confirm that such auth permission is not needed. It uses shadow directly and it already has the appropriate auth_read_shadow() interface call! I am now checking the details... On the 21st of April 2017 15:42:01 CEST, Dominick Grift via refpolicy wrote: >On Fri, Apr 21, 2017 at 03:33:50PM +0200, Guido Trentalancia via >refpolicy wrote: >> It doesn't have a PAM configuration file for the simple reason that >it doesn't use PAM... > >And thus it is not a authlogin login program > >> >> I am now testing the other permissions, it should be easier and safer >than just speculating on the possible behavior. >> >> I getting a very different behavior! >> >> Will get back shortly. >> >> Regards, >> >> Guido >> >> On the 21st April 2017 14:48:48 CEST, Dominick Grift via refpolicy > wrote: >> >On Fri, Apr 21, 2017 at 02:42:46PM +0200, Dominick Grift wrote: >> >> On Fri, Apr 21, 2017 at 10:38:06PM +1000, Russell Coker via >refpolicy >> >wrote: >> >> > On Fri, 21 Apr 2017 10:06:29 PM Guido Trentalancia via refpolicy >> >wrote: >> >> > > > auth_read_shadow(sulogin_t) >> >> > > > >> >> > > >+auth_login_pgm_domain(sulogin_t) >> >> > > >+kernel_read_crypto_sysctls(sulogin_t) >> >> > > >+selinux_set_generic_booleans(sulogin_t) >> >> > > > >> >> > > >What usage need this access? >> >> > > >> >> > > They are dangerous permissions, especially the one that allows >to >> >set the >> >> > > SELinux booleans! >> >> > > >> >> > > Only the system administrator should be permitted to set the >> >booleans >> >> > > interactively through the application... >> >> > >> >> > Sulogin only runs at the console when something goes wrong in >the >> >early boot >> >> > process, and the first thing it does is ask for a root password. >> >> > >> >> > It's simply impossible for sulogin to do what it does without >the >> >first line, >> >> > it is a login program. >> >> >> >> I don't think its a login program from an authlogin perspective. >It >> >has no pam config here on fedora. There are no default contexts for >> >sulogin >> > >> >Ok i might be wrong here with regard there not being default >contexts. >> >I do believe that it somehow uses default contexts but there does >not >> >seem to be a pam config here >> > >> >> >> >> > >> >> > The second is used by exim_t, lpr_t, boinc_t, mailman_cgi_t, and > >> >> > user_mail_domain among others. If we need to restrict access to >> >that then >> >> > exim_t, lpr_t, boinc_t, mailman_cgi_t, and user_mail_domain all >> >deal with >> >> > untrusted data. The domains exim_t, boinc_t, and mailman_cgi_t >are >> >exposed to >> >> > data from the Internet and have that access. >> >> > >> >> > The policy currently has sysadm_shell_domtrans(sulogin_t) which >> >allows sulogin >> >> > to execute "bash -c setsebool" or similar. So allowing it to >set >> >booleans >> >> > directly doesn't really change much. >> >> > >> >> > There is simply no possibility to allow sulogin to do what it is >> >intended to >> >> > do without granting it access to destroy things (at least >> >indirectly). If you >> >> > don't want that then the only option is to remove sulogin. I >guess >> >you could >> >> > submit a patch with a boolean to deny executing sulogin_exec_t >for >> >init if >> >> > that's what you want. >> >> > >> >> > -- >> >> > My Main Blog http://etbe.coker.com.au/ >> >> > My Documents Blog http://doc.coker.com.au/ >> >> > _______________________________________________ >> >> > refpolicy mailing list >> >> > refpolicy at oss.tresys.com >> >> > http://oss.tresys.com/mailman/listinfo/refpolicy >> >> >> >> -- >> >> Key fingerprint = 5F4D 3CDB D3F8 3652 FBD8 02D5 3B6C 5F1D 2C7B >6B02 >> >> >> >>https://sks-keyservers.net/pks/lookup?op=get&search=0x3B6C5F1D2C7B6B02 >> >> Dominick Grift >> >> _______________________________________________ >> refpolicy mailing list >> refpolicy at oss.tresys.com >> http://oss.tresys.com/mailman/listinfo/refpolicy