Uploaded image for project: 'Cassandra'
  1. Cassandra
  2. CASSANDRA-1237

Store AccessLevels externally to IAuthenticator



    • Type: Bug
    • Status: Resolved
    • Priority: Normal
    • Resolution: Fixed
    • Fix Version/s: 0.7 beta 2
    • Component/s: None
    • Labels:
    • Severity:


      Currently, the concept of authentication (proving the identity of a user) is mixed up with permissions (determining whether a user is able to create/read/write databases). Rather than determining the permissions that a user has, the IAuthenticator should only be capable of authenticating a user, and permissions (specifically, an AccessLevel) should be stored consistently by Cassandra.

      EDIT: Adding summary

      In summary, there appear to be 3 distinct options for how to move forward with authorization. Remember that this ticket is about disconnecting authorization (permissions) from authentication (user/group identification), and its goal is to leave authentication pluggable.


      1. Leave authentication and authorization in the same interface. If we choose this option, this ticket is invalid, and CASSANDRA-1271 and CASSANDRA-1320 will add-to/improve IAuthenticator
        • Pros:
          • Least change
        • Cons:
          • Very little actually implemented by Cassandra: burden is on the backend implementors
          • Each combination of authz and authc backends would require a new implementation (PAM for authc + permissions keyspace for authz, for instance), causing an explosion of implementations
      2. Separate out a pluggable IAuthority interface to implement authorization
        1. IAuthenticator interface would be called at login time to determine user/groups membership
        2. IAuthority would be called at operation time with the user/groups determined earlier, and the required permission for the operation
        • Pros:
          • Provides the cleanest separation of concerns
          • Allows plugability for permissions
        • Cons:
          • Pluggability of permissions gains limited benefit
          • IAuthority would need to support callbacks for keyspace/cf creation and removal to keep existing keyspaces in sync with their permissions (although technically, option 1 suffers from this as well)
      3. Separate authorization, but do not make it pluggable
        • This option is implemented by the existing patchset by attaching permissions to metadata, but could have an alternative implementation that stores permissions in a permissions keyspace.
        • Pros:
          • Cassandra controls the scalability of authorization, and can ensure it does not become a bottleneck
        • Cons:
          • Would need to support callbacks for user creation and removal to keep existing users in sync with their permissions


          Issue Links



              • Assignee:
                stuhood Stu Hood
                stuhood Stu Hood
                Stu Hood
                Eric Evans
              • Votes:
                0 Vote for this issue
                3 Start watching this issue


                • Created: