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RBAC Configuration

The RBAC feature enables restriction of access to Argo CD resources. Argo CD does not have its own user management system and has only one built-in user admin. The admin user is a superuser and it has unrestricted access to the system. RBAC requires SSO configuration or one or more local users setup. Once SSO or local users are configured, additional RBAC roles can be defined, and SSO groups or local users can then be mapped to roles.

Basic Built-in Roles

Argo CD has two pre-defined roles but RBAC configuration allows defining roles and groups (see below).

  • role:readonly - read-only access to all resources
  • role:admin - unrestricted access to all resources

These default built-in role definitions can be seen in builtin-policy.csv

RBAC Permission Structure

Breaking down the permissions definition differs slightly between applications and every other resource type in Argo CD.

  • All resources except application-specific permissions (see next bullet):

    p, <role/user/group>, <resource>, <action>, <object>

  • Applications, logs, and exec (which belong to an AppProject):

    p, <role/user/group>, <resource>, <action>, <appproject>/<object>

RBAC Resources and Actions

Resources: clusters, projects, applications, repositories, certificates, accounts, gpgkeys, logs, exec

Actions: get, create, update, delete, sync, override, action/<group/kind/action-name>

Application resources

The resource path for application objects is of the form <project-name>/<application-name>.

Delete access to sub-resources of a project, such as a rollout or a pod, cannot be managed granularly. <project-name>/<application-name> grants access to all subresources of an application.

The action action

The action action corresponds to either built-in resource customizations defined in the Argo CD repository, or to custom resource actions defined by you. The action path is of the form action/<api-group>/<Kind>/<action-name>. For example, a resource customization path resource_customizations/extensions/DaemonSet/actions/restart/action.lua corresponds to the action path action/extensions/DaemonSet/restart. You can also use glob patterns in the action path: action/* (or regex patterns if you have enabled the regex match mode).

exec resource

exec is a special resource. When enabled with the create action, this privilege allows a user to exec into Pods via the Argo CD UI. The functionality is similar to kubectl exec.

exec is a powerful privilege. It allows the user to run arbitrary code on any Pod managed by an Application for which they have create privileges. If the Pod mounts a ServiceAccount token (which is the default behavior of Kubernetes), then the user effectively has the same privileges as that ServiceAccount.

The exec feature is disabled entirely by default. To enable it, set the exec.enabled key to "true" on the argocd-cm ConfigMap. You will also need to add the following to the argocd-api-server Role (if you're using Argo CD in namespaced mode) or ClusterRole (if you're using Argo CD in cluster mode).

- apiGroups:
  - ""
  resources:
  - pods/exec
  verbs:
  - create

Tying It All Together

Additional roles and groups can be configured in argocd-rbac-cm ConfigMap. The example below configures a custom role, named org-admin. The role is assigned to any user which belongs to your-github-org:your-team group. All other users get the default policy of role:readonly, which cannot modify Argo CD settings.

ArgoCD ConfigMap argocd-rbac-cm Example:

apiVersion: v1
kind: ConfigMap
metadata:
  name: argocd-rbac-cm
  namespace: argocd
data:
  policy.default: role:readonly
  policy.csv: |
    p, role:org-admin, applications, *, */*, allow
    p, role:org-admin, clusters, get, *, allow
    p, role:org-admin, repositories, get, *, allow
    p, role:org-admin, repositories, create, *, allow
    p, role:org-admin, repositories, update, *, allow
    p, role:org-admin, repositories, delete, *, allow
    p, role:org-admin, logs, get, *, allow
    p, role:org-admin, exec, create, */*, allow

    g, your-github-org:your-team, role:org-admin

Another policy.csv example might look as follows:

p, role:staging-db-admins, applications, create, staging-db-admins/*, allow
p, role:staging-db-admins, applications, delete, staging-db-admins/*, allow
p, role:staging-db-admins, applications, get, staging-db-admins/*, allow
p, role:staging-db-admins, applications, override, staging-db-admins/*, allow
p, role:staging-db-admins, applications, sync, staging-db-admins/*, allow
p, role:staging-db-admins, applications, update, staging-db-admins/*, allow
p, role:staging-db-admins, logs, get, staging-db-admins/*, allow
p, role:staging-db-admins, exec, create, staging-db-admins/*, allow
p, role:staging-db-admins, projects, get, staging-db-admins, allow
g, db-admins, role:staging-db-admins

This example defines a role called staging-db-admins with eight permissions that allow that role to perform the actions (create/delete/get/override/sync/update applications, get logs, create exec and get appprojects) against * (all) objects in the staging-db-admins Argo CD AppProject.

Anonymous Access

The anonymous access to Argo CD can be enabled using users.anonymous.enabled field in argocd-cm (see argocd-cm.yaml). The anonymous users get default role permissions specified by policy.default in argocd-rbac-cm.yaml. For read-only access you'll want policy.default: role:readonly as above

Validating and testing your RBAC policies

If you want to ensure that your RBAC policies are working as expected, you can use the argocd admin settings rbac command to validate them. This tool allows you to test whether a certain role or subject can perform the requested action with a policy that's not live yet in the system, i.e. from a local file or config map. Additionally, it can be used against the live policy in the cluster your Argo CD is running in.

To check whether your new policy is valid and understood by Argo CD's RBAC implementation, you can use the argocd admin settings rbac validate command.

Validating a policy

To validate a policy stored in a local text file:

argocd admin settings rbac validate --policy-file somepolicy.csv

To validate a policy stored in a local K8s ConfigMap definition in a YAML file:

argocd admin settings rbac validate --policy-file argocd-rbac-cm.yaml

To validate a policy stored in K8s, used by Argo CD in namespace argocd, ensure that your current context in ~/.kube/config is pointing to your Argo CD cluster and give appropriate namespace:

argocd admin settings rbac validate --namespace argocd

Testing a policy

To test whether a role or subject (group or local user) has sufficient permissions to execute certain actions on certain resources, you can use the argocd admin settings rbac can command. Its general syntax is

argocd admin settings rbac can SOMEROLE ACTION RESOURCE SUBRESOURCE [flags]

Given the example from the above ConfigMap, which defines the role role:org-admin, and is stored on your local system as argocd-rbac-cm-yaml, you can test whether that role can do something like follows:

$ argocd admin settings rbac can role:org-admin get applications --policy-file argocd-rbac-cm.yaml
Yes
$ argocd admin settings rbac can role:org-admin get clusters --policy-file argocd-rbac-cm.yaml
Yes
$ argocd admin settings rbac can role:org-admin create clusters 'somecluster' --policy-file argocd-rbac-cm.yaml
No
$ argocd admin settings rbac can role:org-admin create applications 'someproj/someapp' --policy-file argocd-rbac-cm.yaml
Yes

Another example, given the policy above from policy.csv, which defines the role role:staging-db-admins and associates the group db-admins with it. Policy is stored locally as policy.csv:

You can test against the role:

# Plain policy, without a default role defined
$ argocd admin settings rbac can role:staging-db-admins get applications --policy-file policy.csv
No
$ argocd admin settings rbac can role:staging-db-admins get applications 'staging-db-admins/*' --policy-file policy.csv
Yes
# Argo CD augments a builtin policy with two roles defined, the default role
# being 'role:readonly' - You can include a named default role to use:
$ argocd admin settings rbac can role:staging-db-admins get applications --policy-file policy.csv --default-role role:readonly
Yes

Or against the group defined:

$ argocd admin settings rbac can db-admins get applications 'staging-db-admins/*' --policy-file policy.csv
Yes