Alex
Both Abhay and Ramesh are correct. In the Hadoop eco-system we want to ensure
that the users and groups are consistent across all components. And generally,
AD/LDAP or Unix system user/groups are the source of truth.
>>This also means user <--> group mapping in Ranger is NOT the source of
>>truth, but rather a mirror of some other authentication system (OS, LDAP,
>>etc) and a service will need to fetch this information upon user
>>authentication and provide to Ranger ?
Based on some of the earlier discussion on the HAWQ/Ranger integration design
model, it was decided to run the Ranger Plugin in another process. If it is
still the case, you just need to send the user from the HAWQ side and the
Ranger Plugin would be able to get the groups from the AD/LDAP/Unix using
Hadoop Common APIs. Ranger does the same for Kafka and Solr integrations,
because both these systems call the Ranger plugin API only with the username.
Let me know if you need additional information.
Thanks
Bosco
On 3/24/17, 12:50 PM, "Ramesh Mani" <rm...@hortonworks.com> wrote:
Adding to Abhay comment,
In most of the Ranger Plugin from the components side we use
org.apache.hadoop.security.UserGroupInformation API
https://hadoop.apache.org/docs/r1.0.4/api/org/apache/hadoop/security/UserGr
oupInformation.html which will wrap around JAAS and provides the mechanism
to determine the User and Groups. Please check if this can be used.
Thanks,
Ramesh
On 3/24/17, 12:03 PM, "Abhay Kulkarni" <akulka...@hortonworks.com> wrote:
>Hi Alex,
>
>This is exactly right. Users, groups and their associations in Ranger
>(specifically Ranger Admin) are props for being able to define policies.
>They are not the Œsource of truth¹. It is expected that the correct user
><‹-> group associations will be available in the component (service) from
>appropriate authentication system, and provided to Ranger Plugin as part
>of authorization request.
>
>Thanks!
>-Abhay
>
>On 3/24/17, 11:51 AM, "Alexander Denissov" <adenis...@pivotal.io> wrote:
>
>>Hi Ranger experts,
>>
>>We are developing a custom Ranger Plugin for Apache HAWQ(incubating) and
>>noticed that group policies are not behaving as we expected.
>>
>>In Ranger, we define a user U (actually synched from OS). We then
>>manually
>>define group G and enroll user U into it. We then define a policy and
>>grant
>>a privilege to the group G in this policy.
>>
>>On the client side, we do not know that user U belongs to group G, as
>>this
>>information is only defined in Ranger. When we request policy evaluation,
>>we send an empty set for the userGroups API parameter, assuming Ranger
>>will
>>use its internal mapping. But the access is denied by Ranger.
>>
>>So, it seems Ranger will not use the information from its internal user
>><--> group mapping when evaluating policies and would rely on client
>>providing the set of groups for the user explicitly ?
>>
>>This also means user <--> group mapping in Ranger is NOT the source of
>>truth, but rather a mirror of some other authentication system (OS, LDAP,
>>etc) and a service will need to fetch this information upon user
>>authentication and provide to Ranger ?
>>
>>I will appreciate clarification on these points.
>>--
>>Thanks,
>>Alex.
>
>
