在 Openshift 上保护基于路径的路由

Question

My application deployed on openshift has url as https://host:port/app/v1/hello/ I am using ServiceAccount as Oauth client and the provider is Openshift, so I should be redirected to Openshift login page for Authorization.

We have configured openshift/oauth-proxy and it works great. https://github.com/openshift/oauth-proxy/

Now further we have requirement of Path based routing, like if URL has /app/v1 then redirect to Service1 and if /app/v2 then to Service2

Here is the working example of my configuration,

`kind: Template
apiVersion: v1
metadata:
  name: deployment-template
objects:
  - apiVersion: v1
    kind: ServiceAccount
    metadata:
      name: my-service-account
      annotations:
        serviceaccounts.openshift.io/oauth-redirectreference.first: '{"kind":"OAuthRedirectReference","apiVersion":"v1","reference":{"kind":"Route","name":"my-route"}}'
  - apiVersion: v1
    kind: Service
    metadata:
      name: my-service
      annotations:
        service.alpha.openshift.io/serving-cert-secret-name: proxy-tls
    spec:
      selector:
        app: spring-boot-docker-openshift-hello-world
      ports:
        - name: api
          protocol: TCP
          port: 443 #Port the service listens on.
          targetPort: 8443 #Port on the backing pods to which the service forwards connections.
  - apiVersion: v1
    kind: Route
    metadata:
      name: my-route
    spec:
      port:
        targetPort: api
      path: "/"
      to:
        kind: Service
        name: my-service
      tls:
        termination: Reencrypt
  - apiVersion: apps.openshift.io/v1
    kind: DeploymentConfig
    metadata:
      labels:
        app: spring-boot-docker-openshift-hello-world
        version: 0.0.1-SNAPSHOT.1.dev
      name: spring-boot-docker-openshift-hello-world
    spec:
      replicas: 1
      selector:
        app: spring-boot-docker-openshift-hello-world
      strategy:
        rollingParams:
          timeoutSeconds: 3600
        type: Rolling
      template:
        metadata:
          labels:
            app: spring-boot-docker-openshift-hello-world
            version: 0.0.1-SNAPSHOT.1.dev
        spec:
          serviceAccount: my-service-account
          serviceAccountName: my-service-account
          containers:
          - name: spring-boot-docker-openshift-hello-world
            env:
              - name: KUBERNETES_NAMESPACE
                valueFrom:
                  fieldRef:
                    fieldPath: metadata.namespace
            image: pokarjm/spring-boot-docker-openshift-hello-world:0.0.1-SNAPSHOT.1.dev
            imagePullPolicy: IfNotPresent
            securityContext:
              privileged: false
            ports:
              - containerPort: 8080
                protocol: TCP
          - name: oauth-proxy
            image: openshift/oauth-proxy:latest
            imagePullPolicy: IfNotPresent
            ports:
              - containerPort: 8443
                name: public
            args:
              - --https-address=:8443
              - --provider=openshift
              - --openshift-service-account=my-service-account
              - --upstream=http://localhost:8080
              - --tls-cert=/etc/tls/private/tls.crt
              - --tls-key=/etc/tls/private/tls.key
              - --cookie-secret-file=/etc/proxy/secret/session_secret
              - --openshift-ca=/var/run/secrets/kubernetes.io/serviceaccount/ca.crt
              - --openshift-sar={"namespace":"spring-boot-docker-openshift-hello-world","resource":"services","name":"my-service","verb":"get"}
              - --request-logging=true
            volumeMounts:
              - mountPath: /etc/tls/private
                name: proxy-tls
                readOnly: true
              - mountPath: /etc/proxy/secret
                name: oauth-proxy-secret
                readOnly: true
          volumes:
            - name: proxy-tls
              secret:
                defaultMode: 420
                secretName: proxy-tls
            - name: oauth-proxy-secret
              secret:
                defaultMode: 420
                secretName: oauth-proxy-secret
      triggers:
        - type: ConfigChange
`

Now to support path based routing, that is map the request /app/v1 to Service1, I just added the Path in route like below,

- apiVersion: v1
    kind: Route
    metadata:
      name: my-route
    spec:
      port:
        targetPort: api
      path: "/app/v1"
      to:
        kind: Service
        name: my-service
      tls:
        termination: Reencrypt

but with this changes I can see a initial sign in page like below

but after clicking the button above instead of getting the openshift login page, I see below,

If I change the path in route to path: "/" it works and shows login screen. Appreciate any help on fixing path based routing in openshift/oauth-proxy.

Answer 1

Try adding something like --proxy-prefix=/app/v1 , to your oauth proxy container.

Eg:

[...]
        args:
          - --https-address=:8443
          - --provider=openshift
          - --proxy-prefix=/app/v1
          - --openshift-service-account=my-service-account
[...]

Otherwise, the oauth-proxy would assume the application it is serving lies at the root of your Route, breaking the login callback redirection.

---

Now, regarding your question in comments, I'm no sure I got it all myself, I don't have an OpenShift cluster to test this with, ... take it with a pinch of salt, edits welcome, if anyone can get this right.

As far as I understand and recall:

• Client connect to your app, going through your oauth-proxy.
• The proxy sees your client is unauthenticated and requests a token from the Oauth portal, using its client ID and secret (having set openshift-service-account , reads those out of /var/run/secrets/kubernetes.io/serviceaccount/ ). You could instead use client-id=system:serviceaccount:$ns:$sa and client-secret-file=/var/run/secrets/kubernetes.io/serviceaccount/token , if detection somehow doesn't work.
• The Oauth SP checks for our ServiceAccount with an serviceaccounts.openshift.io/oauth-redirectreference annotation (though there's another way to do this, with OauthClient , which I'm less familiar with), matching the client requested application URL. On successful match, SP replies to oauth-proxy with some ephemeral token
• Knowing that token, and the proxy-prefix , the oauth-proxy redirects unauthenticated users to the Oauth login portal, with some encoded callback URL as a GET param
• User logs in against OpenShift users base
• On successful login, the Oauth Portal redirects you to the oauth-proxy, using the callback URL it received from your proxy
• the oauth-proxy redeems its token
• If openshift-sar was defined, oauth-proxy proceeds with some additional check ensuring client is authorized, otherwise any user may log in
• User optionally consent in granting some permissions

In OpenShift context, the initial token requests is done using the login-url param, which defaults to kubernetes.default.svc/oauth/authorize , though in some cases (not sure to remember, some unusual networkpolicies), you may want to force use your OpenShift console FQDN instead.

The token redemption is done through the redeem-url which defaults to kubernetes.default.svc/oauth/token . Again, you could use your public console FQDN here, if SDN otherwise denies this traffic.

So , how is proxy-prefix coming into the picture: only required for your oauth-proxy to build the proper callback URL, for the login form to send you back to the proper sub-path of your application.

And the OAuthRedirectReference is mainly used by OpenShift making sure the client requesting a token is indeed meant to authenticated clients for a given Route. In your case, only matching a FQDN, although I think that in addition to serviceaccounts.openshift.io/oauth-redirectreference.$name: {"kind": ...} , you may also set something like serviceaccounts.openshift.io/oauth-redirecturi.name: my-path