125 lines
4.3 KiB
Markdown
125 lines
4.3 KiB
Markdown
# Running dex as the Kubernetes authenticator
|
|
|
|
Running dex as the Kubernetes authenticator requires.
|
|
|
|
* dex is running on HTTPS.
|
|
* Your browser can navigate to dex at the same address Kubernetes refers to it as.
|
|
|
|
To accomplish this locally, these scripts assume you're using the single host
|
|
vagrant setup provided by the [coreos-kubernetes](
|
|
https://github.com/coreos/coreos-kubernetes) repo with a couple of changes (a
|
|
complete diff is provided at the bottom of this document). Namely that:
|
|
|
|
* The API server isn't running on host port 443.
|
|
* The virtual machine has a populated `/etc/hosts`
|
|
|
|
The following entry must be added to your host's `/etc/hosts` file as well as
|
|
the VM.
|
|
|
|
```
|
|
172.17.4.99 dex.example.com
|
|
```
|
|
|
|
In the future this document will provide instructions for a more general
|
|
Kubernetes installation.
|
|
|
|
Once you have Kubernetes configured, set up the ThirdPartyResources and a
|
|
ConfigMap for dex to use. These run dex as a deployment with configuration and
|
|
storage, allowing it to get started.
|
|
|
|
```
|
|
kubectl create -f thirdpartyresources.yaml
|
|
kubectl create configmap dex-config --from-file=config.yaml=config-k8s.yaml
|
|
kubectl create -f deployment.yaml
|
|
```
|
|
|
|
To get dex running at an HTTPS endpoint, create an ingress controller, some
|
|
self-signed TLS assets and an ingress rule for dex. These TLS assest should
|
|
normally be provided by an actual CA (public or internal).
|
|
|
|
```
|
|
kubectl create -f https://raw.githubusercontent.com/kubernetes/contrib/master/ingress/controllers/nginx/rc.yaml
|
|
./gencert.sh
|
|
kubectl create secret tls dex.example.com.tls --cert=ssl/cert.pem --key=ssl/key.pem
|
|
kubectl create -f dex-ingress.yaml
|
|
```
|
|
|
|
To test that the everything has been installed correctly. Configure a client
|
|
with some credentials, and run the `example-app` (run `make` at the top level
|
|
of this repo if you haven't already). The second command will error out if your
|
|
example-app can't find dex.
|
|
|
|
```
|
|
kubectl create -f client.yaml
|
|
../../bin/example-app --issuer https://dex.example.com --issuer-root-ca ssl/ca.pem
|
|
```
|
|
|
|
Navigate to `127.0.0.1:5555` and try to login. You should be redirected to
|
|
`dex.example.com` with lots of TLS errors. Proceed around them, authorize the
|
|
`example-app`'s OAuth2 client and you should be redirected back to the
|
|
`example-app` with valid OpenID Connect credentials.
|
|
|
|
Finally, to configure Kubernetes to use dex as its authenticator, copy
|
|
`ssl/ca.pem` to `/etc/kubernetes/ssl/openid-ca.pem` onto the VM and update the
|
|
API server's manifest at `/etc/kubernetes/manifests/kube-apiserver.yaml` to add
|
|
the following flags.
|
|
|
|
```
|
|
--oidc-issuer-url=https://dex.example.com
|
|
--oidc-client-id=example-app
|
|
--oidc-ca-file=/etc/kubernetes/ssl/openid-ca.pem
|
|
--oidc-username-claim=email
|
|
--oidc-groups-claim=groups
|
|
```
|
|
|
|
Kick the API server by killing its Docker container, and when it comes up again
|
|
it should be using dex. Login again through the `example-app` and you should be
|
|
able to use the provided token as a bearer token to hit the Kubernetes API.
|
|
|
|
## Changes to coreos-kubernetes
|
|
|
|
The following is a diff to the [coreos-kubernetes](https://github.com/coreos/coreos-kubernetes)
|
|
repo that accomplishes the required changes.
|
|
|
|
```diff
|
|
diff --git a/single-node/user-data b/single-node/user-data
|
|
index f419f09..ed42055 100644
|
|
--- a/single-node/user-data
|
|
+++ b/single-node/user-data
|
|
@@ -80,6 +80,15 @@ function init_flannel {
|
|
}
|
|
|
|
function init_templates {
|
|
+ local TEMPLATE=/etc/hosts
|
|
+ if [ ! -f $TEMPLATE ]; then
|
|
+ echo "TEMPLATE: $TEMPLATE"
|
|
+ mkdir -p $(dirname $TEMPLATE)
|
|
+ cat << EOF > $TEMPLATE
|
|
+172.17.4.99 dex.example.com
|
|
+EOF
|
|
+ fi
|
|
+
|
|
local TEMPLATE=/etc/systemd/system/kubelet.service
|
|
if [ ! -f $TEMPLATE ]; then
|
|
echo "TEMPLATE: $TEMPLATE"
|
|
@@ -195,7 +204,7 @@ spec:
|
|
- --etcd-servers=${ETCD_ENDPOINTS}
|
|
- --allow-privileged=true
|
|
- --service-cluster-ip-range=${SERVICE_IP_RANGE}
|
|
- - --secure-port=443
|
|
+ - --secure-port=8443
|
|
- --advertise-address=${ADVERTISE_IP}
|
|
- --admission-control=NamespaceLifecycle,LimitRanger,ServiceAccount,ResourceQuota
|
|
- --tls-cert-file=/etc/kubernetes/ssl/apiserver.pem
|
|
@@ -211,8 +220,8 @@ spec:
|
|
initialDelaySeconds: 15
|
|
timeoutSeconds: 15
|
|
ports:
|
|
- - containerPort: 443
|
|
- hostPort: 443
|
|
+ - containerPort: 8443
|
|
+ hostPort: 8443
|
|
name: https
|
|
- containerPort: 8080
|
|
hostPort: 8080
|
|
```
|