Mapping LDAP Service Directory Groups to Kong Roles

Service directory mapping allows organizations to use their LDAP Directory for authentication and authorization in Kong Gateway.

After starting Kong Gateway with the desired configuration, you can create new admins whose usernames match those in your LDAP directory. Those users will then be able to accept invitations to join Kong Manager and log in with their LDAP credentials.

How service directory mapping works in Kong:

• Roles are created in Kong Gateway using the Admin API or Kong Manager.
• Groups are created and roles are associated with the groups.
• When users log in to Kong Manager, they get permissions based on the group(s) they belong to.

For example, if a user’s group changes in the service directory, their Kong admin account’s associated role also changes in Kong Gateway the next time they log in to Kong Manager. The mapping removes the task of manually managing access in Kong Gateway, as it makes the service directory the system of record.

When using LDAP service directory mapping, roles assigned to admins are managed by the service directory. If you manually assign or unassign admin roles, changes will be overwritten during the next login.

Prerequisites

• Kong Gateway installed and configured
• Kong Manager access
• A local LDAP directory

Enable LDAP authentication

Configure service directory mapping to use your LDAP directory for authentication and authorization.

1. Start Kong Gateway. From the shell, enter:

    kong start [-c /path/to/kong/conf]
   

2. To enable LDAP Authentication and enforce RBAC for Kong Manager, configure Kong through kong.conf with the following properties:

    enforce_rbac = on
    admin_gui_auth = ldap-auth-advanced
    admin_gui_session_conf = { "secret":"set-your-string-here" }
   

   Kong Manager also uses the Sessions plugin in the background. This plugin (configured with admin_gui_session_conf) requires a secret and is configured securely by default.

   • Under all circumstances, the secret must be manually set to a string.
   • If using HTTP instead of HTTPS, cookie_secure must be manually set to false.
   • If using different domains for the Admin API and Kong Manager, cookie_same_site must be set to Lax.

   Learn more about these properties in Session Security in Kong Manager, and see example configurations.

Configure LDAP authentication

Configure LDAP authentication for Kong Manager with the following properties. Note the attribute variables defined below:

admin_gui_auth_conf = {
 "anonymous":"", \
 "attribute":"<ENTER_YOUR_ATTRIBUTE_HERE>", \
 "bind_dn":"<ENTER_YOUR_BIND_DN_HERE>", \
 "base_dn":"<ENTER_YOUR_BASE_DN_HERE>", \
 "cache_ttl": 2, \
 "header_type":"Basic", \
 "keepalive":60000, \
 "ldap_host":"<ENTER_YOUR_LDAP_HOST_HERE>", \
 "ldap_password":"<ENTER_YOUR_LDAP_PASSWORD_HERE>", \
 "ldap_port":389, \
 "start_tls":false, \
 "timeout":10000, \
 "verify_ldap_host":true, \
 "consumer_by":["username", "custom_id"], \
 "group_base_dn":"<ENTER_YOUR_GROUP_BASE_DN_HERE>",
 "group_name_attribute":"<ENTER_YOUR_GROUP_NAME_ATTRIBUTE_HERE>",
 "group_member_attribute":"<ENTER_YOUR_GROUP_MEMBER_ATTRIBUTE_HERE>",
}

Define roles with permissions

Define roles with permissions in Kong Gateway, using the Admin API’s RBAC endpoints or using Kong Manager’s Teams page. You must manually define which Kong roles correspond to each of the service directory’s groups using either of the following:

• In Kong Manager’s directory mapping section. Find it under Teams > Groups tab.
• With the Admin API’s directory mapping endpoints.

Kong Gateway will not write to the service directory. For example, a Kong Gateway admin cannot create users or groups in the directory. You must create users and groups independently before mapping them to Kong Gateway.

User-admin mapping

To map a service directory user to a Kong admin, map the admin’s username to the name value corresponding to the attribute configured in admin_gui_auth_conf. Create an admin account in Kong Manager or use the Admin API.

For instructions on how to pair the bootstrapped super admin with a directory user, see Set up a directory user as the first super admin.

If you already have admins with assigned roles and want to use group mapping instead, it is necessary to first remove all of their roles. The service directory will serve as the system of record for user privileges. Assigned roles will affect a user’s privileges in addition to any roles mapped from groups.

Group-role assignment

Using service directory mapping, groups are mapped to roles. When a user logs in, they are identified with their admin username and authenticated with the matching user credentials in the service directory. The groups in the service directory are then automatically matched to the associated roles that the organization has defined.

Example

1. Example Corp maps the service directory group, T1-Mgmt, to the Kong role super-admin.
2. Example Corp maps a service directory user, named example-user, to a Kong admin account with the same name, example-user.
3. The user, example-user, is assigned to the group T1-Mgmt in the LDAP Directory.

When example-user logs in as an admin to Kong Manager, they will automatically have the role of super-admin as a result of the mapping.

If Example Corp decides to revoke example-user’s privileges by removing their assignment to T1-Mgmt, they will no longer have the super-admin role when they attempt to log in.

Set up a directory user as the first super admin

Setting up a directory user as the first super admin is recommended by Kong.

The example shows an attribute configured with a unique identifier (UID), and the directory user you want to make the super admin has a distinguished name (DN) entry of UID=example-user:

curl -i -X PATCH https://localhost:8001/admins/kong_admin \
  --header 'Kong-Admin-Token: <RBAC_TOKEN>' \
  --header 'Content-Type: application/json' \
  --data '{"username":"example-user"}'

This user will be able to log in, but until you map a group belonging to example-user to a role, the user will only use the directory for authentication. Once you map the super-admin role to a group that example-user is in, then you can delete the super-admin role from the example-user admin. The group you pick needs to be “super” in your directory, otherwise as other admins log in with a generic group, for example the “employee” group, they will also become super-admins.

Important: If you delete the super-admin role from your only admin, and have not yet mapped the super-admin role to a group that admin belongs to, then you will not be able to log in to Kong Manager.

Alternatives:

• Start Kong with RBAC turned off, map a group to the super-admin role, and then create an admin to correspond to a user belonging to that group. Doing so ensures that the super admin’s privileges are entirely tied to the directory group, whereas bootstrapping a super admin only uses the directory for authentication.

• Create all admin accounts for matching directory users and ensure that their existing groups map to appropriate roles before enforcing RBAC.