Role Based Access Control (RBAC)

This guide will explain how to implement RBAC using Ory Keto.

danger

Implementing RBAC currently is possible, but requires some workarounds. This guide enables RBAC support with Keto but native support is still work in progress. Follow the progress in this issue

Role Based Access Control (RBAC) maps subjects to roles and roles to permissions. The goal of (H)RBAC is to make permission management convenient by grouping subjects in roles and assigning permissions roles. This type of access control is common in web applications where one often encounters roles such as "administrator", "moderator", and so on.

In Hierarchical Role Based Access Control (HRBAC) roles can inherit permissions from other roles. The "administrator" role, for example, could inherit all permissions from the "moderator" role. This reduces duplication and management complexity around defining privileges.

Let's assume that we are building a reporting application and need to have three groups of users with different access levels. We have the following group of reports in our application.

• Financial performance reports
• Marketing performance reports
• Community performance reports

This time we model the access rights using (H)RBAC and the roles community, marketing, finance and admin:

The role admin inherits all privileges from finance, marketing and community

(H)RBAC is everywhere. If you ever installed a forum software such as phpBB or Wordpress, you have definitely encountered ACL, (H)RBAC, or both.

(H)RBAC reduces management complexity and overhead with large user bases. Sometimes however, even (H)RBAC is not enough. An example is when you need to express ownership (e.g. Dilan can only modify his own reports), have attributes (e.g. Dilan needs to have access only during work hours), or in multi-tenant environments.

Benefits:

• Reduces management complexity when many identities share similar permissions.
• Role hierarchies can reduce redundancy even further.
• Is well established and easily understood by many developers as it is a de-facto standard for web applications.

Shortcomings:

• There is no concept of ownership: Dan is the author of article "Hello World" and is thus allowed to update it.
• There is no concept of environment: Dan is allowed to access accounting services when the request comes from IP 10.0.0.3.
• There is no concept of tenants: Dan is allowed to access resources on the "dan's test" tenant.

RBAC with Ory Keto

We need to have three groups, finance, marketing, community. Also, we need to have two namespaces: reports to manage access control and groups to add users to this group

Let's add namespaces to Keto config. here

# ...
namespaces:
  - id: 0
    name: groups
  - id: 1
    name: reports
#...

We can have two types of permission to access reports for granularity. Let's assume that we need edit and view access to the reports.

// View only access for finance department
reports:finance#view@(groups:finance#member)
// View only access for community department
reports:community#view@(groups:community#member)
// View only access for marketing department
reports:marketing#view@(groups:marketing#member)
// Edit access for admin group
reports:finance#edit@(groups:admin#member)
reports:community#edit@(groups:admin#member)
reports:marketing#edit@(groups:admin#member)
reports:finance#view@(groups:admin#member)
reports:community#view@(groups:admin#member)
reports:marketing#view@(groups:admin#member)

Let's assume that we have four people in our organization. Lila is CFO and needs access to financial reports, Hadley works in marketing, and Dilan works as a community manager. Neel is an admin of a system and needs to have edit permissions for reports.

groups:finance#member@Lila
groups:community#member@Dilan
groups:marketing#member@Hadley
groups:admin#member@Neel

Creating Relation Tuples

Let's copy all permissions we created to a policies.rts file with the following content.

reports:finance#view@(groups:finance#member)
reports:community#view@(groups:community#member)
reports:marketing#view@(groups:marketing#member)
reports:finance#edit@(groups:admin#member)
reports:community#edit@(groups:admin#member)
reports:marketing#edit@(groups:admin#member)
reports:finance#view@(groups:admin#member)
reports:community#view@(groups:admin#member)
reports:marketing#view@(groups:admin#member)
groups:finance#member@Lila
groups:community#member@Dilan
groups:marketing#member@Hadley
groups:admin#member@Neel

Then we can run

keto relation-tuple parse policies.rts --format json | \
  keto relation-tuple create - >/dev/null \
  && echo "Successfully created tuple" \
  || echo "Encountered error"

Since Dilan works as a community manager, the following check examples show that he has access only to community reports

keto check Dilan view reports finance
Denied
keto check Dilan view reports community
Allowed
keto check Dilan edit reports community
Denied

Now Dilan decided to also work with marketing. Therefore we need to update his permissions and add him to the marketing group.

groups:marketing#member@Dilan

Now he also has access to marketing reports:

keto check Dilan view reports marketing
Allowed

Display all objects a user has access to

The example below shows you how to get a list of objects Dilan has access to

# Get all groups for Dilan
keto relation-tuple get --subject-id=Dilan --relation=member --format json --read-remote localhost:4466 | jq
{
  "relation_tuples": [
    {
      "namespace": "groups",
      "object": "community",
      "relation": "member",
      "subject_id": "Dilan"
    },
    {
      "namespace": "groups",
      "object": "marketing",
      "relation": "member",
      "subject_id": "Dilan"
    }
  ],
  "next_page_token": ""
}

# Get permissions to objects for marketing group
keto relation-tuple get --subject-set="groups:marketing#member" --format json --read-remote localhost:4466 | jq
{
  "relation_tuples": [
    {
      "namespace": "reports",
      "object": "marketing",
      "relation": "view",
      "subject_set": {
        "namespace": "groups",
        "object": "marketing",
        "relation": "member"
      }
    }
  ],
  "next_page_token": ""
}
# Get permissions to objects for community group
keto relation-tuple get --subject-set="groups:community#member" --format json --read-remote localhost:4466 | jq
{
  "relation_tuples": [
    {
      "namespace": "reports",
      "object": "community",
      "relation": "view",
      "subject_set": {
        "namespace": "groups",
        "object": "community",
        "relation": "member"
      }
    }
  ],
  "next_page_token": ""
}