Introduction 

Goals

• Make CDAP authorization policy consistent across all entities and permissions
• Allow setting granular permissions at dataset level, application level etc. 
• Ranger integration for CDAP authorization
• Improve Sentry data model to fix existing issues seen on customer environment
• Allow admins to use existing role/groups for authorization

User Stories 

• TBD

Design

CDAP Authorization Model

Existing CDAP Authorization Model

The existing CDAP Authorization Model has the following drawbacks:

• Granular permissions

  • Cannot grant a privilege to a user to read only one dataset or one stream in a namespace.
  • Cannot grant a privilege to a user to deploy an application/artifact/dataset/stream without granting write on the namespace.
  • Cannot grant a privilege to a user to start/stop a program without granting READ on the namespace.
• Visibility
  • User who has a privilege on a program cannot see the program in the UI or CLI without having any privilege on the namespace. 
• Inconsistencies 
  • To write to a dataset user needs to have WRITE privilege on the dataset but to write to a stream user needs to have WRITE on the the stream and READ on the namespace.
  • To retrieve dataset properties READ on dataset is required whereas to read stream properties any privilege (READ/WRITE/EXECUTE/ADMIN) is sufficient.
  • ADMIN on an entity allows to delete the entity where ADMIN on entity doesn't allow to CREATE.
  • Dataset read needs namespace READ but dataset write does not need namespace WRITE.
  • TBD Dataset Module Delete All.
• Redundancy
  
  • List and View operations are equivalent but are listed separately in documentation.
  • Dataset READ and Stream READ are redundant because they need Namespace READ permission to be meaningful.

Overview of Proposed Model

We propose the following CDAP Authorization policy which can be defined by the following three principles:

1. Access: 

   • Access defines who can perform an action (READ, WRITE, EXECUTE, ADMIN) on an entity. 

   • Access flows top-down i.e. if an user has READ on namespace it implies that the user has READ on all entities inside the namespace. 

2. Visibility

   • Visibility defines whether an entity is visible to a user or not.
   • If a user has any privilege on an entity, it is visible to the user.
   • Visibility flows bottom-up i.e. if a user has any privilege on a program then the user will be able to see the application that contains the program and namespace that contains the application.

3. Grant

   • Grant is defined as action of giving a privilege on an entity to a user.
   • To grant privileges on an entity ADMIN on the entity is required.
   • Grant flows top-down i.e. if a user has ADMIN on namespace then the user can grant privileges on all entities inside the namespace.

• Note: CDAP Instance is not part of the privilege hierarchy.

Decouple entity existence from privilege:

In addition CDAP will now support creating privileges for entities that are yet to be created. This will allow admins to grant fine grained privileges on entities. For example, an admin can grant a user ADMIN on an application before the application is deployed. This will allow the user to deploy only this specific application without having any other access to the namespace.

Decouple entity creation and granting privileges:

TBD

Based on the above, we propose the following changes to the authorization matrix:

Instance

ADMIN on an Instance allows user to create Namespaces in the instance. No other operations are defined as of now.

Also Instance is not a part of privilege hierarchy.

Namespaces

CDAP Ranger Integration

Introduction

Apache Ranger provides a centralized security framework

Design

CDAP Sentry Extension Improvements

• Has no grant

Existing Roles/Groups for Authorization

API changes

New Programmatic APIs

New Java APIs introduced (both user facing and internal)

Deprecated Programmatic APIs

New REST APIs

Deprecated REST API

CLI Impact or Changes

• Impact #1
• Impact #2
• Impact #3

UI Impact or Changes

• Impact #1
• Impact #2
• Impact #3

Security Impact 

What's the impact on Authorization and how does the design take care of this aspect

Impact on Infrastructure Outages 

System behavior (if applicable - document impact on downstream [ YARN, HBase etc ] component failures) and how does the design take care of these aspect

Test Scenarios

Releases

Release X.Y.Z

Release X.Y.Z

Related Work

• Work #1
• Work #2
• Work #3

Future work