[wildfly-dev] problems with the Elytron permission-mapping config model

Tue Mar 27 08:06:51 EDT 2018

How do you cope with things like a login module stack in the security
subsystem?  That is also ordered where the order has a very specific
meaning.  I haven't checked the configuration recently but doesn't
configuration for jgroups also handle the configuration in an ordered way
that an administrator could choose to modify?

The proposal we have so far is to remove the need for the manipulation of
permissions in the ordered list as other subsystems are added / removed -
at this point the remaining config in the permission mapper should either
match the default we ship or if it is modified this should be as a result
of administrator action so should be preserved as is.

The problem we have with the resource now is it must be preserved for
backwards compatibility.  Broadly this means we have the following two
requirements: -
 1 - Any changes we make must be transformable to the prior version of the
resource.
 2 - XML configuration for a prior version of the resource must be
convertible to the new version.

Alternatively we could redesign a new resource from scratch to provide
model based permission mapping but a redesign from scratch is unlikely to
completely cover #1 and #2 so we could end up with a deprecated resource
which is not immediately removable although if we can achieve #1 removal
possibly could be faster.

But is all this necessary at the moment?  Especially as at the moment we do
have a proposal that moves the permissions we know need to be updated to an
identifiable resource.

Darran.

On Tue, 27 Mar 2018 at 12:45 Alexey Loubyansky <alexey.loubyansky at redhat.com>
wrote:

> On Tue, Mar 27, 2018 at 1:23 PM, Darran Lofthouse <
> darran.lofthouse at redhat.com> wrote:
>
>> The part that I am still missing is if we remove the need to manipulate
>> an ordered list as other subsystems are added and removed how is the
>> presence of the ordered list still an issue?  I am sure we have other
>> examples of ordered lists out there.
>>
>
> Actually, mainly in Elytron. The list in itself is not an issue, the
> identity of the items is. If there is a list that can be modified by
> various parties (end user, as a consequence of integration of other
> components, etc) there is a problem of merging these modifications or even
> identifying them in terms which items changed and how. Identifying user
> changes since the last official update (with the goal to preserve them
> after the next update) becomes a problem as well.
>
> Alexey
>
>
>> Darran.
>>
>>
>> On Tue, 27 Mar 2018 at 12:15 Alexey Loubyansky <
>> alexey.loubyansky at redhat.com> wrote:
>>
>>> On Tue, Mar 27, 2018 at 12:34 PM, Darran Lofthouse <
>>> darran.lofthouse at redhat.com> wrote:
>>>
>>>> Ok so lets switch this another way.
>>>>
>>>> If the addition from other subsystems was to be eliminated is there
>>>> still a provisioning issue?
>>>>
>>>
>>> The provisioning issue is related to the structure of the configuration
>>> model (to be more precise the representation of the resource in the domain
>>> management model since this is what is being manipulated). There are other
>>> examples of subsystems requiring configuration of other features, e.g. some
>>> subsystems may require specific socket-bindings. There is no problem with
>>> that from the provisioning perspective because the model allows to check
>>> whether the required socket-binding is already present in the config,
>>> whether its parameters need any adjustments and if the socket-binding is
>>> missing from the config it can be added.
>>>
>>> Thanks,
>>> Alexey
>>>
>>>
>>>>
>>>> On Fri, 23 Mar 2018 at 20:52 Brian Stansberry <
>>>> brian.stansberry at redhat.com> wrote:
>>>>
>>>>> On Fri, Mar 23, 2018 at 12:56 PM, Darran Lofthouse <
>>>>> darran.lofthouse at jboss.com> wrote:
>>>>>
>>>>>> On Fri, 23 Mar 2018 at 17:50 Alexey Loubyansky <
>>>>>> alexey.loubyansky at redhat.com> wrote:
>>>>>>
>>>>>>> On Fri, Mar 23, 2018 at 6:20 PM, Farah Juma <fjuma at redhat.com>
>>>>>>> wrote:
>>>>>>>
>>>>>>>> A solution to part of the problem mentioned in WFCORE-3596 that was
>>>>>>>> discussed is to introduce the concept of named permission sets. In
>>>>>>>> particular, instead of having a permission-mapping reference permissions,
>>>>>>>> it would instead reference named permission-sets. This would allow the
>>>>>>>> provisioning tool to be able to add/remove permissions to/from a default
>>>>>>>> permission-set based on the presence/absence of a specific subsystem when
>>>>>>>> generating the default configuration. However, as Alexey pointed out, this
>>>>>>>> doesn't solve the problem of knowing which permission-mapping a
>>>>>>>> permission-set should be added to when attempting to preserve user
>>>>>>>> configuration changes for patching, version updates, etc.
>>>>>>>>
>>>>>>>
>>>>>>> Right. It does not change the permission-mappings, they remain to be
>>>>>>> a list of items with no identity. Which is the fundamental problem.
>>>>>>>
>>>>>>
>>>>>> But why is that a problem? I think that is the piece still missing.
>>>>>>
>>>>>> By moving the list of the permissions into a single named resource
>>>>>> the tooling no longer has a need to be performing the manipulation within
>>>>>> the simple permission mapper so that can be left to the administrator to
>>>>>> look after independently.
>>>>>>
>>>>>
>>>>> Is your question why is it a problem to give these things an identity?
>>>>> If so, I have the same question, although I don't think Alexey's the one to
>>>>> come up with the identity.
>>>>>
>>>>> Or is your question why is not having an identity a problem? If so, is
>>>>> it correct to say that getting rid of this bit of wrongness is the problem:
>>>>>
>>>>>
>>>>> https://github.com/wildfly/wildfly-core/blob/master/elytron/src/main/resources/subsystem-templates/elytron.xml#L125
>>>>>
>>>>> Basically right there elytron is speculatively providing configuration
>>>>> rightly owned by other subsystems. To do this correctly, each of those
>>>>> permissions should be part of the config established by other parts of the
>>>>> system. The provisioning tool is expected to do it correctly. And doing
>>>>> that requires some sort of identity for each item in the set. . Installing
>>>>> a feature should involve adding independent, identifiable chunks of config,
>>>>> not manipulating an attribute of some chunk of config owned by a different
>>>>> feature. Manipulating an attribute is not feasible and isn't correct.
>>>>>
>>>>>
>>>>>>
>>>>>>>
>>>>>>> Thanks,
>>>>>>> Alexey
>>>>>>>
>>>>>>> Thanks,
>>>>>>>> Farah
>>>>>>>>
>>>>>>>> On Fri, Mar 23, 2018 at 11:55 AM, Alexey Loubyansky <
>>>>>>>> alexey.loubyansky at redhat.com> wrote:
>>>>>>>>
>>>>>>>>> While this is addressed mainly to the Elytron team, it seems like
>>>>>>>>> we would appreciate opinions from other colleagues since we are basically
>>>>>>>>> stuck discussing possible ways to resolve
>>>>>>>>> https://issues.jboss.org/browse/WFCORE-3596
>>>>>>>>>
>>>>>>>>> The description in the jira is pretty brief assuming people know
>>>>>>>>> what that is about, since it's been raised before multiple times. Here is
>>>>>>>>> what it is about fundamentally.
>>>>>>>>>
>>>>>>>>> If a configuration model (of a subsystem or any other component)
>>>>>>>>> includes a list of configurable units (let's assume XML elements for
>>>>>>>>> simplicity) that don't have any identity (unique id/name/path/etc) this is
>>>>>>>>> a big problem for supporting patching and version updates preserving user
>>>>>>>>> configuration changes. Or simply customizing the default config model using
>>>>>>>>> a tool. By a big problem I mean it's simply not going to work reliably.
>>>>>>>>>
>>>>>>>>> As a simple exercise that demonstrates the issue, imagine you have
>>>>>>>>> two configs each of which includes a list of these configurable units that
>>>>>>>>> have no identity. Now try to identify the difference between the two lists.
>>>>>>>>> Or merge them with one overwriting the other. Basically components w/o an
>>>>>>>>> identity can not be manipulated. You can only add them but not modify or
>>>>>>>>> even remove (unless their index in the list is a constant value of course).
>>>>>>>>>
>>>>>>>>> I don't think I've seen any issue of this kind in our (WF/EAP)
>>>>>>>>> configs except for the Elytron's permission-mapping's. (If somebody knows
>>>>>>>>> such components please let me know).
>>>>>>>>> If I misunderstand the Elytron config model or approaching this
>>>>>>>>> from a wrong angle, please let me know.
>>>>>>>>>
>>>>>>>>> Question for the Elytron team: is the problem I am describing
>>>>>>>>> clear? Do you admit it as a problem?
>>>>>>>>>
>>>>>>>>> Thanks,
>>>>>>>>> Alexey
>>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>> _______________________________________________
>>>>>> wildfly-dev mailing list
>>>>>> wildfly-dev at lists.jboss.org
>>>>>> https://lists.jboss.org/mailman/listinfo/wildfly-dev
>>>>>>
>>>>>
>>>>>
>>>>>
>>>>> --
>>>>> Brian Stansberry
>>>>> Manager, Senior Principal Software Engineer
>>>>> Red Hat
>>>>>
>>>>
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