Support external-auth /oauth2

[tamalsaha]

https://github.com/kubernetes/ingress-nginx/blob/master/docs/examples/external-auth/README.md

[tamalsaha]

I looked into the nginx controller again today, It seems that its should be possible to achieve oauth proxy with a combination of oauth_proxy pod and custom backend rules (that will redirect to oauth login page, if certain cookie is missing)

It seems that the oauth annotations are used to automatically generate the backend rules.

[diptadas]

Requirements

• bitly/oauth2_proxy
• TimWolla/haproxy-auth-request
• HAProxy 1.8.4

Demo without SSL

HAProxy config

$ cat /etc/haproxy/haproxy.cfg

global
        lua-load auth-request.lua

defaults
        mode    http
        timeout connect 5000
        timeout client  50000
        timeout server  50000

backend auth_request
        server auth_request 127.0.0.1:4180

backend app
        http-request lua.auth-request auth_request /oauth2/auth
        http-request redirect location /oauth2/start?rd=http://voyager.appscode.ninja if ! { var(txn.auth_response_successful) -m bool }

        server app 138.197.59.213:80

frontend http
        bind *:80

        acl acl_host hdr(host) -i voyager.appscode.ninja
        acl acl_host hdr(host) -i voyager.appscode.ninja:80

        acl acl_path_oauth2 path_beg /oauth2
        use_backend auth_request if acl_path_oauth2 acl_host

        use_backend app if acl_host

Setup github oauth app

callback-url: http://voyager.appscode.ninja/oauth2

Run oauth2_proxy

$ ./oauth2_proxy \
-provider=github \
-client-id=... \
-client-secret=... \
-email-domain=* \
-upstream=file:///dev/null \
-cookie-secret=secretsecret \
-cookie-secure=false

Demo with SSL

Notes

• Set cookie-secure=true (default value)
• Use https in redirect-url and github callback-url
• Redirect http to https, otherwise you will get permission denied: http: named cookie not present error

Generate certs

$ openssl req -x509 -nodes -days 365 -newkey rsa:2048 -keyout /tmp/tls.key -out /tmp/tls.crt -subj "/CN=voyager.appscode.ninja"
$ cat /tmp/tls.crt /tmp/tls.key | tee /tmp/tls.pem

HAProxy config

$ cat /etc/haproxy/haproxy.cfg

global
        lua-load auth-request.lua
        tune.ssl.default-dh-param 2048

defaults
        mode    http
        timeout connect 5000
        timeout client  50000
        timeout server  50000

backend auth_request
        server auth_request 127.0.0.1:4180

backend app
        http-request lua.auth-request auth_request /oauth2/auth
        http-request redirect location /oauth2/start?rd=https://voyager.appscode.ninja if ! { var(txn.auth_response_successful) -m bool }

        server app 138.197.59.213:80

frontend http
        bind *:80

        bind *:443 ssl crt /tmp/tls.pem
        redirect scheme https if !{ ssl_fc }

        acl acl_host hdr(host) -i voyager.appscode.ninja
        acl acl_host hdr(host) -i voyager.appscode.ninja:80

        acl acl_path_oauth2 path_beg /oauth2
        use_backend auth_request if acl_path_oauth2 acl_host

        use_backend app if acl_host

Setup github oauth app

callback-url: https://voyager.appscode.ninja/oauth2

Run oauth2_proxy

$ ./oauth2_proxy \
-provider=github \
-client-id=... \
-client-secret=... \
-email-domain=* \
-upstream=file:///dev/null \
-cookie-secret=secretsecret

[tamalsaha]

apiVersion: voyager.appscode.com/v1beta1
kind: Ingress
metadata:
  name: auth-ingress
  namespace: default
spec:
  frontendRules:
  - port: 80
    auth:
      oauth2:
      - <config> abc.com
        backends:
        - name1
        - name2
        - name3
      - <config> xyz.com
        backends:
        - name5
        - name6
        - name7
  rules:
  - host: 2421e8df.ngrok.io
    http:
      nodePort: 32666
      paths:
      - path: /app
        backend:
          serviceName: test-server
          servicePort: 80
      - path: /oauth2
        backend:
          name: auth-be
          serviceName: oauth2-proxy
          servicePort: 4180

[tamalsaha]

Fixed in #954