Using OIDC plugin

Kong Enterprise’s OIDC plugin can authenticate requests using OpenID Connect protocol. This guide shows a basic example of how to setup the OIDC plugin using the Ingress Controller.

Note: This works only with Enterprise version of Kong.

Installation

Please follow the deployment documentation to install enterprise version of the Kubernetes Ingress Controller.

Testing Connectivity to Kong

This guide assumes that the PROXY_IP environment variable is set to contain the IP address or URL pointing to Kong. Please follow one of the deployment guides to configure this environment variable.

If everything is setup correctly, making a request to Kong should return HTTP 404 Not Found.

$ curl -i $PROXY_IP
HTTP/1.1 404 Not Found
Content-Type: application/json; charset=utf-8
Connection: keep-alive
Content-Length: 48
Server: kong/1.2.1

{"message":"no Route matched with those values"}

This is expected as Kong does not yet know how to proxy the request.

Setup a Sample Service

For the purpose of this guide, we will setup an httpbin service in the cluster and proxy it.

kubectl apply -f https://bit.ly/k8s-httpbin
service/httpbin created
deployment.apps/httpbin created

Create an Ingress rule to proxy the httpbin service we just created:

$ echo '
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: demo
spec:
  ingressClassName: kong
  rules:
  - host: 192.0.2.8.xip.io
    http:
      paths:
      - path: /
        pathType: ImplementationSpecific
        backend:
          service:
            name: httpbin
            port:
              number: 80
' | kubectl apply -f -
ingress.extensions/demo created

We are using 192.0.2.8.xip.io as our host, you can use any domain name of your choice. A domain name is a prerequisite for this guide. For demo purpose, we are using xip.io service to avoid setting up a DNS record.

Test the Ingress rule:

$ curl -i 192.0.2.8.xip.io/status/200
HTTP/1.1 200 OK
Content-Type: text/html; charset=utf-8
Content-Length: 0
Connection: keep-alive
Server: gunicorn/19.9.0
Access-Control-Allow-Origin: *
Access-Control-Allow-Credentials: true
X-Kong-Upstream-Latency: 2
X-Kong-Proxy-Latency: 1
Via: kong/3.1.1

Next, open a browser and browse to http://192.0.2.8.xip.io. You should see landing page same as httpbin.org.

Setup OIDC plugin

Now we are going to protect our dummy service with OpenID Connect protocol using Google as our identity provider.

First, setup an OAuth 2.0 application in Google.

Once you have setup your application in Google, use the client ID and client secret and create a KongPlugin resource in Kubernetes:

$ echo "
apiVersion: configuration.konghq.com/v1
kind: KongPlugin
metadata:
  name: oidc-auth
config:
  issuer: https://accounts.google.com/.well-known/openid-configuration
  client_id:
  - <client-id>
  client_secret:
  - <client-secret>
  redirect_uri:
  - http://192.0.2.8.xip.io
plugin: openid-connect
" | kubectl apply -f -
kongplugin.configuration.konghq.com/oidc-auth created

The redirect_uri parameter must be a URI that matches the Ingress rule we created earlier. You must also add it to your Google OIDC configuration

Next, enable the plugin on our Ingress:

$ kubectl patch ing demo -p '{"metadata":{"annotations":{"konghq.com/plugins":"oidc-auth"}}}'
ingress.extensions/demo patched

Test

Now, if you visit the host you have set up in your Ingress resource, Kong should redirect you to Google to verify your identity. Once you identify yourself, you should be able to browse our dummy service once again.

This basic configuration permits any user with a valid Google account to access the dummy service. For setting up more complicated authentication and authorization flows, please read plugin docs.