[Freeipa-devel] [DESIGN][UPDATE] Time-Based HBAC Policies

[Martin Basti]

On 19.08.2016 12:37, Pavel Vomacka wrote:
>
>
> On 08/16/2016 08:21 AM, Stanislav Laznicka wrote:
>> On 08/12/2016 06:48 PM, Petr Spacek wrote:
>>> On 11.8.2016 12:34, Stanislav Laznicka wrote:
>>>> Hello,
>>>>
>>>> I updated the design of the Time-Based HBAC Policies according to the
>>>> discussion we led here earlier. Please check the design page
>>>> http://www.freeipa.org/page/V4/Time-Based_Account_Policies. The 
>>>> biggest
>>>> changes are in the Implementation and Feature Management sections. 
>>>> I also
>>>> added a short How to Use section.
>> Thank you for the review! I will add some comments inline.
>>> Nice page!
>>>
>>> On the high level it all makes sense.
>>>
>>> ad LDAP schema
>>> ==============
>>> 1) Why accessTime attribute is MAY in ipaTimeRule object class?
>>> Does it make sense to have the object without accessTime? I do not 
>>> think so.
>> My idea was that we allow users prepare a few time rule objects 
>> before filling them with the actual times.
>>> Also, it could be good to add description attribute to the object 
>>> class and
>>> incorporate it into commands (including find).
>>>
>> Definitely a good idea, I will work that in.
>>> 2) Besides all this, I spent few minutes in dark history of IPA. The
>>> accessTime attribute was introduced back in 2009 in commit
>>> "55ba300c7cb59cf05b16cc01281f51d93eb25acf" aka "Incorporate new 
>>> schema for IPAv2".
>>>
>>> The commit does not contain any reasoning for the change but I can 
>>> see that
>>> the attribute is already used as MAY in old object classes 
>>> ipaHBACRule and
>>> ipaSELinuxUserMap.
>>>
>>> Is any of these a problem?
>> I believe that the accessTime attribute was originally brought to IPA 
>> when there was an implementation of time policies for HBAC objects 
>> and it's been rotting there ever since those capabilities were 
>> removed. We may eventually use a new attribute for storage of the 
>> time strings as accessTime by definition is multi-valued which is not 
>> what's currently desired (although we may end up with it some day in 
>> the future). However, I don't think any other use of accessTime 
>> should be a problem as it's been obsoleted for a long time.
>>> Why is it even in ipaSELinuxUserMap object class?
>> I'm sorry to say I have no idea. I used it for what it originally was 
>> - a means for storing time strings at HBAC rules.
>>> Commit
>>> 55512dc938eb4a9a6655e473beab587e340af55c does not mention any reason 
>>> for doing so.
>>>
>>> I cannot see any other problem so the low-level stuff is good and 
>>> can be
>>> implemented.
>>>
>>>
>>> ad User interface
>>> =================
>>> We need to polish the user interface so it really usable.
>>>
>>> At least the web interface should contain some shortcuts. E.g. when 
>>> I'm adding
>>> a new HBAC rule, the "time" section should contain also "something" to
>>> immediately add new time rule so I do not need to go to time rules 
>>> first and
>>> then go back to HBAC page.
> I'm definitely for creating a field where admin can choose a existing 
> time rule when creating a new HBAC. But I'm not sure about possibility 
> to create and define new time rule in dialog for creating new HBAC. I 
> think that mixing these two things together is like a possibility to 
> create a new user when you are creating a user group. Which is mixing 
> two different things together. I can imagine a button like "Create 
> HBAC and add a new time rule to it" which could store new HBAC rule 
> and immediately take admin to the page (or dialog) where admin can 
> create a new time rule with prefilled HBAC rule. But as you write 
> below it would be good to discuss it with some UX designer.

I'm not UX guru, but if you add button there and show dialog window to 
create new timerule and then automatically assign it to the HBACrule it 
may work for me :)

>>>
>>> Similarly, dialog for rule modification should allow to easily 
>>> change all the
>>> values, warn if time rules is shared, and also have an easy way to
>>> 'disconnect' the time rule, i.e. make a copy of it and edit only the 
>>> new copy
>>> (instead of the shared original).
>>>
> All of these points are really good.

>>> All these are user interface things not affecting the low-level stuff.
>>>
>>>
>>> Maybe you should sat down with some UX designer, talk about these 
>>> cases and
>>> draw some hand-made pictures.
>> I will add Pavel V. to CC, we may want to discuss this.
>>> I do not believe that this will require any changes in schema so you 
>>> can
>>> polish SSSD and framework implementation in meantime.
>>>
>>> On the link below is a PROTOTYPE-patched FreeIPA that covers most of 
>>> the CLI
>>> functionality (except for the creation of iCalendar strings from 
>>> options) for
>>> better illustration of the design.
>>>
>>> https://github.com/stlaz/freeipa/tree/timerules_2
>>> Honestly I did not look at the code today :-)
>>>
>>> Overall, I'm glad to see current proposal. After so many iteration, 
>>> we reached
>>> something which does not have any glaring problem :-)
>> It definitely felt better to be writing it with all the previous 
>> knowledge. Thank you! :-)
>

LGTM with all previous comments


(Nitpick mode enabled: True)
1.
It may not be clear from design that client is actually SSSD, and not 
IPA CLI client. Please write explicitly there that HBAC time rules are 
enforced by SSSD with libical in client side sections

2.
Is there any design for SSSD part? If yes, it should be linked to this 
(probably client section)

3.
timerule-mod, timerule-show should show all HBAC rules that are using it 
(Should be done by framework almost automatically, but explicit is 
better than implicit, please make note there).

4.
timerule-del should prevent deletion of timerule if it is used by any 
HBAC rule (we can discuss this)

5.
WebUI: it may be nice to have warning shown when user is editing time 
rule that is used by more than one HBACrule (even confirmation dialog 
would be nice)

(Nitpick mode enable: False)
6.
IMO we should add timerule-test (pick correct name) to test if given 
time/date value matches timerule

7.
We should also extend hbac*-test with timerules (would be nice to 
mention in design)

Martin^2