Ok, it looks like we want to fail on anything in /etc/polkit-1 that
contains 'return polkit.Result.YES' and that would be the equivalent of
checking for NOPASSWD in sudo.
But you can pass so many ways:
return "yes";
return 'y' + 'e' + 's';
tmp = "yes";
return tmp;
etc.
But you can also modify rules that restrict actions to local, redefine admin
groups, call out to programs, etc.
-Steve
Now, I don't know how to handle cases where things are loaded
from
somewhere else.
Does anyone know how to print all active policykit rules with content?
Thanks,
Trevor
On Mon, Sep 17, 2018 at 11:33 AM Trevor Vaughan <tvaughan(a)onyxpoint.com>
wrote:
> Yes, spirit of the rule is exactly what I am saying.
>
> In old polkit this was pretty easy (INI-style). In new polkit, I can do
> Javascript-fu and make whatever mess I'd like to make.
>
> Basically, industry caused a validation issue and I was a bit surprised
> since I thought we all agreed that configuration files that were
> executable languages were a bad idea back in the late 90's.
>
> But, that doesn't fix the issue that we have to write rules about this if
> it's going to be an enabled capability. You have to be root to edit
> /etc/sudoers as well. So, either we should cover both, or ignore both
> since they're essentially the same capability.
>
> Trevor
>
> On Mon, Sep 17, 2018 at 11:23 AM Sean <smalder73(a)gmail.com> wrote:
>> I think the gist of what Trevor's driving at is the "Spirit of the
Rule"
>> which requires privilege escalation to pass an authentication challenge.
>> He is using 'password' but the challenge could be satisfied by a number
>> of
>> methods - pkcs#11 token, ssh-key, etc.
>>
>> With sudo, NOPASSWD rules are not compliant. Polkit, if it is a gateway
>> for privilege escalation, should follow the spirit of this rule, for the
>> same reasons it exists for sudo.
>>
>> --Sean
>>
>> On Mon, Sep 17, 2018 at 11:07 AM Steve Grubb <sgrubb(a)redhat.com> wrote:
>>> On Monday, September 17, 2018 10:50:28 AM EDT Trevor Vaughan wrote:
>>> > Just tinkering around:
>>> >
>>> > If you have /etc/polkit/rules.d/10-nopasswd_hack.rules with the
>>>
>>> following
>>>
>>> > content:
>>> >
>>> > polkit.addRule(function(action, subject) {
>>> >
>>> > if (action.id == "org.freedesktop.policykit.exec"
&&
>>> >
>>> > subject.isInGroup("wheel"))
>>> >
>>> > {
>>> >
>>> > return polkit.Result.YES;
>>> >
>>> > }
>>> >
>>> > });
>>> >
>>> > Then you can run the following to get a root shell with absolutely no
>>> > password prompt.
>>> >
>>> > pkexec -u root /bin/bash
>>>
>>> Yes. But you need root to put it there. My thoughts on polkit rules is
>>> that
>>> about all you can do is sha256 hash the files. The language is so
>>> complex
>>> that parsing it is impossible. You can say what should exist and what
>>> its
>>> hash should be. It goes downhill from there.
>>>
>>> -Steve
>>>
>>> > On Mon, Sep 17, 2018 at 10:19 AM Trevor Vaughan <
>>>
>>> tvaughan(a)onyxpoint.com>
>>>
>>> > wrote:
>>> > > On a default installation? They can't but I think they can
twiddle
>>>
>>> things
>>>
>>> > > in NetworkManager from the GUI IIRC.
>>> > >
>>> > > But they also can't get to root via 'sudo' and we have
rules for
>>>
>>> that.
>>>
>>> > > Polkit is basically sudo for DBus stuff and we have rules around
>>> > > what
>>> > > should, and should not, be done with sudo so I guess I expect the
>>>
>>> same
>>>
>>> > > thing with polkit.
>>> > >
>>> > > For instance, I could use pkexec to run arbitrary commands as
root
>>> > > without
>>> > > a password if I have a rule set up for it. But, unlike sudo,
there
>>>
>>> isn't
>>>
>>> > > a
>>> > > rule saying not to do that and a method to check for it.
>>> > >
>>> > > Thanks,
>>> > >
>>> > > Trevor
>>> > >
>>> > > On Mon, Sep 17, 2018 at 9:45 AM Thomas Haller
<thaller(a)redhat.com>
>>>
>>> wrote:
>>> > >> On Mon, 2018-09-17 at 09:19 -0400, Trevor Vaughan wrote:
>>> > >> > Otherwise, there's a
>>> > >> > lovely gaping hole in the system security that can
effectively
>>> > >> > be
>>> > >> > used to run pretty much anything with root permissions.
>>> > >>
>>> > >> Hi,
>>> > >>
>>> > >> This makes me wonder. How can an unpriviledged user get root
>>> > >> permissions on a default installation of RHEL? Either in
general,
>>> > >> or
>>> > >> specifically using NetworkManager.
>>> > >>
>>> > >>
>>> > >> best,
>>> > >> Thomas
>>> > >
>>> > > --
>>> > > Trevor Vaughan
>>> > > Vice President, Onyx Point, Inc
>>> > > (410) 541-6699 x788
>>> > >
>>> > > -- This account not approved for unencrypted proprietary
>>> > > information
>>>
>>> --
>>>
>>>
>>>
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> --
> Trevor Vaughan
> Vice President, Onyx Point, Inc
> (410) 541-6699 x788
>
> -- This account not approved for unencrypted proprietary information --