Set up an external authentication and authorization to protect the workloads in your cluster. For example, you can set up basic, passthrough, API key, OAuth, OPA, or LDAP authentication.

About external auth

API gateways act as a control point for the outside world to access the various application services that run in your environment, whether monoliths, microservices, or serverless functions. In microservices or hybrid application architecture, these workloads accept an increasingly large number of requests.

Requests can be anonymous or authenticated. You can use external authentication to establish and validate who the client is, which service the client is requesting, and what authorization the request has.

Gloo external auth architecture

Gloo Mesh Gateway provides two resources to help you manage external auth: an external auth server and policy.

ExtAuthServer: To enforce external auth, each workspace must have an external auth server. You can let Gloo Mesh Gateway create a default configuration for you within your cluster. The default setup gives the you benefits of running within the cluster, including observability, telemetry, and mutual TLS. Also, each team gets its own server to use, as you must have one external auth server per workspace. You can also configure your own external auth server within your Gloo environment or external to the Gloo environment.

ExtAuthPolicy: The external auth server uses external auth policies to enforce authentication and authorization of matching traffic. You can match traffic by selecting routes or destinations. If you don’t select any routes or destinations, an external auth policy is applied to all destinations by default. You cannot apply more than one external auth policy to the same route or destination. Currently, destinations can be backed by Kubernetes services. Gloo virtual destinations or Gloo external services are not supported.

Supported types of external auth policies

Select the external auth type that meets your security requirements.

The external auth policy spec consists of a series of configs that are executed in sequence. If any of the authentication configs fail, the request is denied by default.

  • Basic: Authenticate requests with a basic dictionary of usernames and passwords.
  • API keys: Authenticate requests by using an API key.
  • LDAP: Authenticate requests against membership information that is stored in a Lightweight Directory Access Protocol (LDAP) server.
  • OIDC and OAuth: Use OpenID Connect (OIDC) with the OAuth 2.0 protocol to have an external identity provider authenticate requests with an access token.
  • OPA: Enforce Open Policy Agent (OPA) policies for more fine-grained access control.
  • For simple verification, JSON web token (JWT): Control access or route traffic based on verified claims in a JSON web token (JWT).
  • Passthrough: Authenticate requests with an external gRPC service.

Key benefits

Gloo Mesh Gateway provides a set of custom resources to make it even easier to set up external auth for all of the microservices in your environment.

  • Scalable: Gloo Mesh Gateway gives you a set of reusable external auth resources that use Kubernetes selectors to automatically scale as your policies and workloads grow.
  • Reusable for cluster ingress and service mesh traffic: You can use the same resources to apply a policy to both traffic into your service mesh (ingress or “north-south”) and across the services in your mesh (“east-west”). Such reuse lets you use the Gateway and Enterprise editions of Gloo Mesh together easily.
  • Persona-driven: As a platform administrator, you can set up the Gloo Mesh Gateway external auth server while registering your workload clusters. Then, your operators create the external auth policies that your developers can use across their services simply through Kubernetes labels.
  • Combinable: You can use external auth policies with many other types of policies, such as JWT, rate limit, traffic management, and other policies. With these policies, you can create a flexible and secure security posture.

External auth API reference

For more information, see the API docs for the external auth server and policy resources.