2015-11-23 11:31:00

by Laurent Bigonville

[permalink] [raw]
Subject: [refpolicy] Transition not working as expected with boolean cron_userdomain_transition set to on

Hi,

While testing my patch for the at daemon, I think I also found a bug in
the policy.

With the cron_userdomain_transition boolean set to off I see the
following behavior, user bigon is unconfined_u, test is user_u and
test_staff is staff_u

bigon at soldur:~$ /usr/sbin/getdefaultcon bigon system_u:system_r:crond_t:s0
unconfined_u:unconfined_r:unconfined_cronjob_t:s0-s0:c0.c1023
bigon at soldur:~$ /usr/sbin/getdefaultcon test system_u:system_r:crond_t:s0
user_u:user_r:cronjob_t:s0
bigon at soldur:~$ /usr/sbin/getdefaultcon test_staff
system_u:system_r:crond_t:s0
staff_u:staff_r:cronjob_t:s0


Everything seems OK here.

But when I toggle the boolean to on, I see the following behavior:

bigon at soldur:~$ /usr/sbin/getdefaultcon bigon system_u:system_r:crond_t:s0
unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023
bigon at soldur:~$ /usr/sbin/getdefaultcon test system_u:system_r:crond_t:s0
/usr/sbin/getdefaultcon: Invalid argument
bigon at soldur:~$ /usr/sbin/getdefaultcon test_staff
system_u:system_r:crond_t:s0
staff_u:sysadm_r:sysadm_t:s0

As you can see a default context cannot be computed for the user_u user
and the staff_u domain is transitioned to sysadm_r:sysadm_t (not sure
this is intended)

In the fedora policy I've found this patch
https://github.com/fedora-selinux/selinux-policy/commit/28afa6f6438070902daca6ecb5d97abad7d53a0d

If I'm _adding_ the user context to the default context

bigon at soldur:~$ /usr/sbin/getdefaultcon bigon system_u:system_r:crond_t:s0
unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023
bigon at soldur:~$ /usr/sbin/getdefaultcon test system_u:system_r:crond_t:s0
user_u:user_r:user_t:s0
bigon at soldur:~$ /usr/sbin/getdefaultcon test_staff
system_u:system_r:crond_t:s0
staff_u:staff_r:staff_t:s0

I've attached a patch, am I understanding everything correctly here?

Cheers,

Laurent Bigonville
-------------- next part --------------
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2015-11-23 12:00:15

by Dominick Grift

[permalink] [raw]
Subject: [refpolicy] Transition not working as expected with boolean cron_userdomain_transition set to on

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA512

On Mon, Nov 23, 2015 at 12:31:00PM +0100, Laurent Bigonville wrote:
> Hi,
>
> While testing my patch for the at daemon, I think I also found a bug in the
> policy.
>
> With the cron_userdomain_transition boolean set to off I see the following
> behavior, user bigon is unconfined_u, test is user_u and test_staff is
> staff_u
>
> bigon at soldur:~$ /usr/sbin/getdefaultcon bigon system_u:system_r:crond_t:s0
> unconfined_u:unconfined_r:unconfined_cronjob_t:s0-s0:c0.c1023
> bigon at soldur:~$ /usr/sbin/getdefaultcon test system_u:system_r:crond_t:s0
> user_u:user_r:cronjob_t:s0
> bigon at soldur:~$ /usr/sbin/getdefaultcon test_staff
> system_u:system_r:crond_t:s0
> staff_u:staff_r:cronjob_t:s0
>
>
> Everything seems OK here.
>
> But when I toggle the boolean to on, I see the following behavior:
>
> bigon at soldur:~$ /usr/sbin/getdefaultcon bigon system_u:system_r:crond_t:s0
> unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023
> bigon at soldur:~$ /usr/sbin/getdefaultcon test system_u:system_r:crond_t:s0
> /usr/sbin/getdefaultcon: Invalid argument
> bigon at soldur:~$ /usr/sbin/getdefaultcon test_staff
> system_u:system_r:crond_t:s0
> staff_u:sysadm_r:sysadm_t:s0
>
> As you can see a default context cannot be computed for the user_u user and
> the staff_u domain is transitioned to sysadm_r:sysadm_t (not sure this is
> intended)
>
> In the fedora policy I've found this patch https://github.com/fedora-selinux/selinux-policy/commit/28afa6f6438070902daca6ecb5d97abad7d53a0d
>
> If I'm _adding_ the user context to the default context
>
> bigon at soldur:~$ /usr/sbin/getdefaultcon bigon system_u:system_r:crond_t:s0
> unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023
> bigon at soldur:~$ /usr/sbin/getdefaultcon test system_u:system_r:crond_t:s0
> user_u:user_r:user_t:s0
> bigon at soldur:~$ /usr/sbin/getdefaultcon test_staff
> system_u:system_r:crond_t:s0
> staff_u:staff_r:staff_t:s0
>
> I've attached a patch, am I understanding everything correctly here?
>
> Cheers,
>
> Laurent Bigonville

> >From c8aa69e51d8781da782a50dbdf20b258288093d4 Mon Sep 17 00:00:00 2001
> From: Laurent Bigonville <[email protected]>
> Date: Mon, 23 Nov 2015 12:25:13 +0100
> Subject: [PATCH] Allow the user cronjobs to run in their userdomain
>
> When cron_userdomain_transition boolean is set to on, the user cronjobs
> are supposed to run in their domains. Without this patch the default
> context is not properly computed:
>
> $ /usr/sbin/getdefaultcon user_u system_u:system_r:crond_t:s0
> /usr/sbin/getdefaultcon: Invalid argument
> $ /usr/sbin/getdefaultcon staff_u system_u:system_r:crond_t:s0
> staff_u:sysadm_r:sysadm_t:s0

this is not a accurate description since it expects a user name and not a
selinux user id (right?)

>
> With this patch applied:
>
> $ /usr/sbin/getdefaultcon user_u system_u:system_r:crond_t:s0
> user_u:user_r:user_t:s0
> $ /usr/sbin/getdefaultcon staff_ system_u:system_r:crond_t:s0
> staff_u:staff_r:staff_t:s0

idem ditto

> ---
> config/appconfig-mcs/staff_u_default_contexts | 2 +-
> config/appconfig-mcs/user_u_default_contexts | 2 +-
> config/appconfig-mls/staff_u_default_contexts | 2 +-
> config/appconfig-mls/user_u_default_contexts | 2 +-
> config/appconfig-standard/staff_u_default_contexts | 2 +-
> config/appconfig-standard/user_u_default_contexts | 2 +-
> 6 files changed, 6 insertions(+), 6 deletions(-)
>
> diff --git a/config/appconfig-mcs/staff_u_default_contexts b/config/appconfig-mcs/staff_u_default_contexts
> index 881a292..5606c4e 100644
> --- a/config/appconfig-mcs/staff_u_default_contexts
> +++ b/config/appconfig-mcs/staff_u_default_contexts
> @@ -1,7 +1,7 @@
> system_r:local_login_t:s0 staff_r:staff_t:s0 sysadm_r:sysadm_t:s0
> system_r:remote_login_t:s0 staff_r:staff_t:s0
> system_r:sshd_t:s0 staff_r:staff_t:s0 sysadm_r:sysadm_t:s0
> -system_r:crond_t:s0 staff_r:cronjob_t:s0
> +system_r:crond_t:s0 staff_r:staff_t:s0 staff_r:cronjob_t:s0
> system_r:xdm_t:s0 staff_r:staff_t:s0
> staff_r:staff_su_t:s0 staff_r:staff_t:s0
> staff_r:staff_sudo_t:s0 staff_r:staff_t:s0
> diff --git a/config/appconfig-mcs/user_u_default_contexts b/config/appconfig-mcs/user_u_default_contexts
> index cacbc93..56d6071 100644
> --- a/config/appconfig-mcs/user_u_default_contexts
> +++ b/config/appconfig-mcs/user_u_default_contexts
> @@ -1,7 +1,7 @@
> system_r:local_login_t:s0 user_r:user_t:s0
> system_r:remote_login_t:s0 user_r:user_t:s0
> system_r:sshd_t:s0 user_r:user_t:s0
> -system_r:crond_t:s0 user_r:cronjob_t:s0
> +system_r:crond_t:s0 user_r:user_t:s0 user_r:cronjob_t:s0
> system_r:xdm_t:s0 user_r:user_t:s0
> user_r:user_su_t:s0 user_r:user_t:s0
> user_r:user_sudo_t:s0 user_r:user_t:s0
> diff --git a/config/appconfig-mls/staff_u_default_contexts b/config/appconfig-mls/staff_u_default_contexts
> index 881a292..5606c4e 100644
> --- a/config/appconfig-mls/staff_u_default_contexts
> +++ b/config/appconfig-mls/staff_u_default_contexts
> @@ -1,7 +1,7 @@
> system_r:local_login_t:s0 staff_r:staff_t:s0 sysadm_r:sysadm_t:s0
> system_r:remote_login_t:s0 staff_r:staff_t:s0
> system_r:sshd_t:s0 staff_r:staff_t:s0 sysadm_r:sysadm_t:s0
> -system_r:crond_t:s0 staff_r:cronjob_t:s0
> +system_r:crond_t:s0 staff_r:staff_t:s0 staff_r:cronjob_t:s0
> system_r:xdm_t:s0 staff_r:staff_t:s0
> staff_r:staff_su_t:s0 staff_r:staff_t:s0
> staff_r:staff_sudo_t:s0 staff_r:staff_t:s0
> diff --git a/config/appconfig-mls/user_u_default_contexts b/config/appconfig-mls/user_u_default_contexts
> index cacbc93..56d6071 100644
> --- a/config/appconfig-mls/user_u_default_contexts
> +++ b/config/appconfig-mls/user_u_default_contexts
> @@ -1,7 +1,7 @@
> system_r:local_login_t:s0 user_r:user_t:s0
> system_r:remote_login_t:s0 user_r:user_t:s0
> system_r:sshd_t:s0 user_r:user_t:s0
> -system_r:crond_t:s0 user_r:cronjob_t:s0
> +system_r:crond_t:s0 user_r:user_t:s0 user_r:cronjob_t:s0
> system_r:xdm_t:s0 user_r:user_t:s0
> user_r:user_su_t:s0 user_r:user_t:s0
> user_r:user_sudo_t:s0 user_r:user_t:s0
> diff --git a/config/appconfig-standard/staff_u_default_contexts b/config/appconfig-standard/staff_u_default_contexts
> index c2a5ea8..300694c 100644
> --- a/config/appconfig-standard/staff_u_default_contexts
> +++ b/config/appconfig-standard/staff_u_default_contexts
> @@ -1,7 +1,7 @@
> system_r:local_login_t staff_r:staff_t sysadm_r:sysadm_t
> system_r:remote_login_t staff_r:staff_t
> system_r:sshd_t staff_r:staff_t sysadm_r:sysadm_t
> -system_r:crond_t staff_r:cronjob_t
> +system_r:crond_t staff_r:staff_t staff_r:cronjob_t
> system_r:xdm_t staff_r:staff_t
> staff_r:staff_su_t staff_r:staff_t
> staff_r:staff_sudo_t staff_r:staff_t
> diff --git a/config/appconfig-standard/user_u_default_contexts b/config/appconfig-standard/user_u_default_contexts
> index f5bfac3..63b7eec 100644
> --- a/config/appconfig-standard/user_u_default_contexts
> +++ b/config/appconfig-standard/user_u_default_contexts
> @@ -1,7 +1,7 @@
> system_r:local_login_t user_r:user_t
> system_r:remote_login_t user_r:user_t
> system_r:sshd_t user_r:user_t
> -system_r:crond_t user_r:cronjob_t
> +system_r:crond_t user_r:user_t user_r:cronjob_t
> system_r:xdm_t user_r:user_t
> user_r:user_su_t user_r:user_t
> user_r:user_sudo_t user_r:user_t
> --
> 2.6.2
>

> _______________________________________________
> refpolicy mailing list
> refpolicy at oss.tresys.com
> http://oss.tresys.com/mailman/listinfo/refpolicy


- --
02DFF788
4D30 903A 1CF3 B756 FB48 1514 3148 83A2 02DF F788
https://sks-keyservers.net/pks/lookup?op=get&search=0x314883A202DFF788
Dominick Grift
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2015-11-23 12:15:07

by Laurent Bigonville

[permalink] [raw]
Subject: [refpolicy] Transition not working as expected with boolean cron_userdomain_transition set to on

Le 23/11/15 13:00, Dominick Grift a ?crit :
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA512
>
> On Mon, Nov 23, 2015 at 12:31:00PM +0100, Laurent Bigonville wrote:
>> [...]
>>
>>
>> When cron_userdomain_transition boolean is set to on, the user cronjobs
>> are supposed to run in their domains. Without this patch the default
>> context is not properly computed:
>>
>> $ /usr/sbin/getdefaultcon user_u system_u:system_r:crond_t:s0
>> /usr/sbin/getdefaultcon: Invalid argument
>> $ /usr/sbin/getdefaultcon staff_u system_u:system_r:crond_t:s0
>> staff_u:sysadm_r:sysadm_t:s0
> this is not a accurate description since it expects a user name and not a
> selinux user id (right?)
>
>> With this patch applied:
>>
>> $ /usr/sbin/getdefaultcon user_u system_u:system_r:crond_t:s0
>> user_u:user_r:user_t:s0
>> $ /usr/sbin/getdefaultcon staff_ system_u:system_r:crond_t:s0
>> staff_u:staff_r:staff_t:s0
> idem ditto

Yes indeed, it was to make the thing more clear for the reader

2015-11-23 12:39:24

by Dominick Grift

[permalink] [raw]
Subject: [refpolicy] Transition not working as expected with boolean cron_userdomain_transition set to on

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA512

On Mon, Nov 23, 2015 at 01:15:07PM +0100, Laurent Bigonville wrote:
> Le 23/11/15 13:00, Dominick Grift a ?crit :
> > -----BEGIN PGP SIGNED MESSAGE-----
> > Hash: SHA512
> >
> > On Mon, Nov 23, 2015 at 12:31:00PM +0100, Laurent Bigonville wrote:
> >> [...]
> >>
> >>
> >> When cron_userdomain_transition boolean is set to on, the user cronjobs
> >> are supposed to run in their domains. Without this patch the default
> >> context is not properly computed:
> >>
> >> $ /usr/sbin/getdefaultcon user_u system_u:system_r:crond_t:s0
> >> /usr/sbin/getdefaultcon: Invalid argument
> >> $ /usr/sbin/getdefaultcon staff_u system_u:system_r:crond_t:s0
> >> staff_u:sysadm_r:sysadm_t:s0
> > this is not a accurate description since it expects a user name and not a
> > selinux user id (right?)
> >
> >> With this patch applied:
> >>
> >> $ /usr/sbin/getdefaultcon user_u system_u:system_r:crond_t:s0
> >> user_u:user_r:user_t:s0
> >> $ /usr/sbin/getdefaultcon staff_ system_u:system_r:crond_t:s0
> >> staff_u:staff_r:staff_t:s0
> > idem ditto
>
> Yes indeed, it was to make the thing more clear for the reader


I do not think that this attempt succeeds, instead it is actually
confusing.

> _______________________________________________
> refpolicy mailing list
> refpolicy at oss.tresys.com
> http://oss.tresys.com/mailman/listinfo/refpolicy

- --
02DFF788
4D30 903A 1CF3 B756 FB48 1514 3148 83A2 02DF F788
https://sks-keyservers.net/pks/lookup?op=get&search=0x314883A202DFF788
Dominick Grift
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2015-12-01 15:50:45

by cpebenito

[permalink] [raw]
Subject: [refpolicy] Transition not working as expected with boolean cron_userdomain_transition set to on

On 11/23/2015 6:31 AM, Laurent Bigonville wrote:
> Hi,
>
> While testing my patch for the at daemon, I think I also found a bug in
> the policy.
>
> With the cron_userdomain_transition boolean set to off I see the
> following behavior, user bigon is unconfined_u, test is user_u and
> test_staff is staff_u
>
> bigon at soldur:~$ /usr/sbin/getdefaultcon bigon system_u:system_r:crond_t:s0
> unconfined_u:unconfined_r:unconfined_cronjob_t:s0-s0:c0.c1023
> bigon at soldur:~$ /usr/sbin/getdefaultcon test system_u:system_r:crond_t:s0
> user_u:user_r:cronjob_t:s0
> bigon at soldur:~$ /usr/sbin/getdefaultcon test_staff
> system_u:system_r:crond_t:s0
> staff_u:staff_r:cronjob_t:s0
>
>
> Everything seems OK here.
>
> But when I toggle the boolean to on, I see the following behavior:
>
> bigon at soldur:~$ /usr/sbin/getdefaultcon bigon system_u:system_r:crond_t:s0
> unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023
> bigon at soldur:~$ /usr/sbin/getdefaultcon test system_u:system_r:crond_t:s0
> /usr/sbin/getdefaultcon: Invalid argument
> bigon at soldur:~$ /usr/sbin/getdefaultcon test_staff
> system_u:system_r:crond_t:s0
> staff_u:sysadm_r:sysadm_t:s0
>
> As you can see a default context cannot be computed for the user_u user
> and the staff_u domain is transitioned to sysadm_r:sysadm_t (not sure
> this is intended)
>
> In the fedora policy I've found this patch
> https://github.com/fedora-selinux/selinux-policy/commit/28afa6f6438070902daca6ecb5d97abad7d53a0d
>
>
> If I'm _adding_ the user context to the default context
>
> bigon at soldur:~$ /usr/sbin/getdefaultcon bigon system_u:system_r:crond_t:s0
> unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023
> bigon at soldur:~$ /usr/sbin/getdefaultcon test system_u:system_r:crond_t:s0
> user_u:user_r:user_t:s0
> bigon at soldur:~$ /usr/sbin/getdefaultcon test_staff
> system_u:system_r:crond_t:s0
> staff_u:staff_r:staff_t:s0
>
> I've attached a patch, am I understanding everything correctly here?

This makes sense, though the default_context files should probably be
updated similarly.


--
Chris PeBenito
Tresys Technology, LLC
http://www.tresys.com | oss.tresys.com

2015-12-01 16:26:11

by Laurent Bigonville

[permalink] [raw]
Subject: [refpolicy] Transition not working as expected with boolean cron_userdomain_transition set to on

Le 01/12/15 16:50, Christopher J. PeBenito a ?crit :
> On 11/23/2015 6:31 AM, Laurent Bigonville wrote:
>> Hi,
>>
>> While testing my patch for the at daemon, I think I also found a bug in
>> the policy.
>>
>> With the cron_userdomain_transition boolean set to off I see the
>> following behavior, user bigon is unconfined_u, test is user_u and
>> test_staff is staff_u
>>
>> bigon at soldur:~$ /usr/sbin/getdefaultcon bigon system_u:system_r:crond_t:s0
>> unconfined_u:unconfined_r:unconfined_cronjob_t:s0-s0:c0.c1023
>> bigon at soldur:~$ /usr/sbin/getdefaultcon test system_u:system_r:crond_t:s0
>> user_u:user_r:cronjob_t:s0
>> bigon at soldur:~$ /usr/sbin/getdefaultcon test_staff
>> system_u:system_r:crond_t:s0
>> staff_u:staff_r:cronjob_t:s0
>>
>>
>> Everything seems OK here.
>>
>> But when I toggle the boolean to on, I see the following behavior:
>>
>> bigon at soldur:~$ /usr/sbin/getdefaultcon bigon system_u:system_r:crond_t:s0
>> unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023
>> bigon at soldur:~$ /usr/sbin/getdefaultcon test system_u:system_r:crond_t:s0
>> /usr/sbin/getdefaultcon: Invalid argument
>> bigon at soldur:~$ /usr/sbin/getdefaultcon test_staff
>> system_u:system_r:crond_t:s0
>> staff_u:sysadm_r:sysadm_t:s0
>>
>> As you can see a default context cannot be computed for the user_u user
>> and the staff_u domain is transitioned to sysadm_r:sysadm_t (not sure
>> this is intended)
>>
>> In the fedora policy I've found this patch
>> https://github.com/fedora-selinux/selinux-policy/commit/28afa6f6438070902daca6ecb5d97abad7d53a0d
>>
>>
>> If I'm _adding_ the user context to the default context
>>
>> bigon at soldur:~$ /usr/sbin/getdefaultcon bigon system_u:system_r:crond_t:s0
>> unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023
>> bigon at soldur:~$ /usr/sbin/getdefaultcon test system_u:system_r:crond_t:s0
>> user_u:user_r:user_t:s0
>> bigon at soldur:~$ /usr/sbin/getdefaultcon test_staff
>> system_u:system_r:crond_t:s0
>> staff_u:staff_r:staff_t:s0
>>
>> I've attached a patch, am I understanding everything correctly here?
> This makes sense, though the default_context files should probably be
> updated similarly.
Is the order relevant here?

2015-12-02 14:35:36

by cpebenito

[permalink] [raw]
Subject: [refpolicy] Transition not working as expected with boolean cron_userdomain_transition set to on

On 12/1/2015 11:26 AM, Laurent Bigonville wrote:
> Le 01/12/15 16:50, Christopher J. PeBenito a ?crit :
>> On 11/23/2015 6:31 AM, Laurent Bigonville wrote:
>>> Hi,
>>>
>>> While testing my patch for the at daemon, I think I also found a bug in
>>> the policy.
>>>
>>> With the cron_userdomain_transition boolean set to off I see the
>>> following behavior, user bigon is unconfined_u, test is user_u and
>>> test_staff is staff_u
>>>
>>> bigon at soldur:~$ /usr/sbin/getdefaultcon bigon system_u:system_r:crond_t:s0
>>> unconfined_u:unconfined_r:unconfined_cronjob_t:s0-s0:c0.c1023
>>> bigon at soldur:~$ /usr/sbin/getdefaultcon test system_u:system_r:crond_t:s0
>>> user_u:user_r:cronjob_t:s0
>>> bigon at soldur:~$ /usr/sbin/getdefaultcon test_staff
>>> system_u:system_r:crond_t:s0
>>> staff_u:staff_r:cronjob_t:s0
>>>
>>>
>>> Everything seems OK here.
>>>
>>> But when I toggle the boolean to on, I see the following behavior:
>>>
>>> bigon at soldur:~$ /usr/sbin/getdefaultcon bigon system_u:system_r:crond_t:s0
>>> unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023
>>> bigon at soldur:~$ /usr/sbin/getdefaultcon test system_u:system_r:crond_t:s0
>>> /usr/sbin/getdefaultcon: Invalid argument
>>> bigon at soldur:~$ /usr/sbin/getdefaultcon test_staff
>>> system_u:system_r:crond_t:s0
>>> staff_u:sysadm_r:sysadm_t:s0
>>>
>>> As you can see a default context cannot be computed for the user_u user
>>> and the staff_u domain is transitioned to sysadm_r:sysadm_t (not sure
>>> this is intended)
>>>
>>> In the fedora policy I've found this patch
>>> https://github.com/fedora-selinux/selinux-policy/commit/28afa6f6438070902daca6ecb5d97abad7d53a0d
>>>
>>>
>>> If I'm _adding_ the user context to the default context
>>>
>>> bigon at soldur:~$ /usr/sbin/getdefaultcon bigon system_u:system_r:crond_t:s0
>>> unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023
>>> bigon at soldur:~$ /usr/sbin/getdefaultcon test system_u:system_r:crond_t:s0
>>> user_u:user_r:user_t:s0
>>> bigon at soldur:~$ /usr/sbin/getdefaultcon test_staff
>>> system_u:system_r:crond_t:s0
>>> staff_u:staff_r:staff_t:s0
>>>
>>> I've attached a patch, am I understanding everything correctly here?
>> This makes sense, though the default_context files should probably be
>> updated similarly.
> Is the order relevant here?

For each line, the order is relevant. The libraries will choose the
first partial context that will result in a valid context. I'd have to
look at the code to see if it will skip partial contexts if the context
is valid but the transition is denied.

--
Chris PeBenito
Tresys Technology, LLC
http://www.tresys.com | oss.tresys.com

2015-12-03 14:33:22

by Laurent Bigonville

[permalink] [raw]
Subject: [refpolicy] Transition not working as expected with boolean cron_userdomain_transition set to on

Le 02/12/15 15:35, Christopher J. PeBenito a ?crit :
> On 12/1/2015 11:26 AM, Laurent Bigonville wrote:
>> Le 01/12/15 16:50, Christopher J. PeBenito a ?crit :
>>> This makes sense, though the default_context files should probably
>>> be updated similarly.
>> Is the order relevant here?
> For each line, the order is relevant. The libraries will choose the
> first partial context that will result in a valid context. I'd have to
> look at the code to see if it will skip partial contexts if the context
> is valid but the transition is denied.
And in this precise case, do you have a specific order for these
contexts in the default_contexts file?

2015-12-03 15:57:08

by cpebenito

[permalink] [raw]
Subject: [refpolicy] Transition not working as expected with boolean cron_userdomain_transition set to on

On 12/3/2015 9:33 AM, Laurent Bigonville wrote:
> Le 02/12/15 15:35, Christopher J. PeBenito a ?crit :
>> On 12/1/2015 11:26 AM, Laurent Bigonville wrote:
>>> Le 01/12/15 16:50, Christopher J. PeBenito a ?crit :
>>>> This makes sense, though the default_context files should probably
>>>> be updated similarly.
>>> Is the order relevant here?
>> For each line, the order is relevant. The libraries will choose the
>> first partial context that will result in a valid context. I'd have to
>> look at the code to see if it will skip partial contexts if the context
>> is valid but the transition is denied.
> And in this precise case, do you have a specific order for these
> contexts in the default_contexts file?

I think it should be like the user default_context files, where the user
domains are first, so those are chosen if the cron_userdomain_transition
is true. If false, then it should fall through to the cronjob domains.

--
Chris PeBenito
Tresys Technology, LLC
http://www.tresys.com | oss.tresys.com