RE: [xacml] Groups - XACML v3.0 Obligation and Advice Authority (OAA) Pr

Thanks Steven for posting this.

In Section 2 there is a use-case which motivates the profile. To summarize, your use-case requires:

- Bob can “create”, “read”, “update” and “destroy” documents.

- Alice can only “read” document.

- “Create”, “update” and “destroy” by anyone must be logged.

- Any operation on sensitive resources must take approval.

You have argued that adding the obligations requires splitting the authorization rules, but I don’t see why this is necessary. Correct me if I am wrong but I think these requirements can be formulated by the following PolicySet without splitting the rules:

(I have attached a PDF if you are reading in plain text):

=================================================

PolicySet 1 (deny-overrides)
- PolicySet 1.1 (deny-unless-permit)
  - Policy: 1.1.1 (deny-overrides)
    - If Resource.type=document:
    - Rule: 1.1.1.1:
      - Permit, if Subject.id=Alice, and Action.id=read
    - Rule: 1.1.1.2:
      - Permit, if Subject.id=Bob and Action.id in {create, read, update, destroy}
- Policy: 1.2 (deny-overrides)
  - Rule 1.2.1: CUP-log
    - Permit if Action.id in {create, update, destroy }, and Resource.type=document:
    - Obligation (OnPermit): log
  - Rule 1.2.2: Sensitive-docs
    - Permit if Resource.approval-required=true and Action.id in { create, read, update, destroy}:
    - Obligation (OnPermit): approval-required

=================================================

Suppose Bob wants to update a sensitive document. This will match policyset 1, 1.1, and 1.1.1 and causes rule 1.1.1.2 to evaluate, permitting the access. But since the overarching combining algorithm is deny-overrides, policy 1.2 is also evaluated. Again since the combing algorithm is deny-override, both rules are evaluated triggering both obligations to log and take approval.

Any other authorization rule can go under policyset 1.1 and any other obligation rule can go under policy 1.2.

Regards,

Mohammad Jafari, Ph.D.

Security Architect, Edmond Scientific Company

From: xacml@lists.oasis-open.org [mailto:xacml@lists.oasis-open.org] On Behalf Of Steven Legg
Sent: Monday, May 27, 2013 7:56 PM
To: xacml@lists.oasis-open.org
Subject: [xacml] Groups - XACML v3.0 Obligation and Advice Authority (OAA) Profile Version 1.0 uploaded

Submitter's message
This is the initial draft for the Obligation and Advice Authority Profile.
-- Dr. Steven Legg

Document Name: XACML v3.0 Obligation and Advice Authority (OAA) Profile Version 1.0

Description
This specification defines a new XACML system entity, the Obligation and
Advice Authority (OAA), which makes obligations and advice easier to manage
by separating the determination of applicable obligations and advice from
the determination of the access decision by the PDP.
Download Latest Revision
Public Download Link

Submitter: Dr. Steven Legg
Group: OASIS eXtensible Access Control Markup Language (XACML) TC
Folder: Specifications and Working Drafts
Date submitted: 2013-05-27 18:56:15

xacml message