certificates/autocert/INSTALL.md
2019-01-17 16:07:27 -08:00

132 lines
4.5 KiB
Markdown

### Create a CA
Set your `STEPPATH` to a working directory where we can stage our CA artifacts before we push them to kubernetes. You can delete this directory once installation is complete.
```
$ export STEPPATH=$(mktemp -d /tmp/step.XXX)
$ step path
/tmp/step.0kE
```
Run `step ca init` to generate a root certificate and CA configuration for your cluster. You'll be prompted for a password that will be used to encrypt key material.
```
$ step ca init \
--name Autocert \
--dns "ca.step.svc.cluster.local,127.0.0.1" \
--address ":4443" \
--provisioner admin \
--with-ca-url "ca.step.svc.cluster.local"
```
For older versions of `step` run this command without the flags.
Add provisioning credentials for use by `autocert`. You'll be prompted for a password for `autocert`.
```
$ step ca provisioner add autocert --create
```
For older versions of `step`:
* Run `step ca init` and follow prompts
* Edit `$(step path)/config/ca.json` and change base paths to `/home/step`
* Edit `$(step path)/config/defaults.json` to change base paths to `/home/step` and remove port from CA URL
```
$ sed -i "" "s|$(step path)|/home/step/.step|g" $(step path)/config/ca.json
$ sed -i "" "s|$(step path)|/home/step/.step|g" $(step path)/config/defaults.json
$ sed -i "" "s|ca.step.svc.cluster.local:4443|ca.step.svc.cluster.local|" $(step path)/config/defaults.json
```
### Install the CA in Kubernetes
We'll install our CA and the `autocert` controller in the `step` namespace.
```
$ kubectl create namespace step
```
To install the CA we need to configmap the CA certificates, signing keys, and configuration artifacts. Note that key material is encrypted so we don't need to use secrets.
```
$ kubectl -n step create configmap config --from-file $(step path)/config
$ kubectl -n step create configmap certs --from-file $(step path)/certs
$ kubectl -n step create configmap secrets --from-file $(step path)/secrets
```
But we will need to create secrets for the CA and autocert to decrypt their keys:
```
$ kubectl -n step create secret generic ca-password --from-literal password=<ca-password>
$ kubectl -n step create secret generic autocert-password --from-literal password=<autocert-password>
```
Where `<ca-password>` is the password you entered during `step ca init` and `<autocert-password>` is the password you entered during `step ca provisioner add`.
Next, we'll install the CA.
```
$ kubectl apply -f https://raw.githubusercontent.com/smallstep/certificates/master/autocert/install/01-step-ca.yaml
```
Once you've done this you can delete the temporary `$STEPPATH` directory and `unset STEPPATH` (though you may want to retain it as a backup).
### Install `autocert` in Kubernetes
Install the `autocert` controller.
```
$ kubectl apply -f https://raw.githubusercontent.com/smallstep/certificates/master/autocert/install/02-autocert.yaml
```
Autocert creates secrets containing single-use bootstrap tokens for pods to authenticate with the CA and obtain a certificate. The tokens are automatically cleaned up after they expire. To do this, `autocert` needs permission to create and delete secrets in your cluster.
If you have RBAC enabled in your cluster, apply `rbac.yaml` to give `autocert` these permissions.
```
$ kubectl apply -f https://raw.githubusercontent.com/smallstep/certificates/master/autocert/install/03-rbac.yaml
```
Finally, register the `autocert` mutation webhook with kubernetes.
```
$ cat <<EOF | kubectl apply -f -
apiVersion: admissionregistration.k8s.io/v1beta1
kind: MutatingWebhookConfiguration
metadata:
name: autocert-webhook-config
labels: {app: controller}
webhooks:
- name: autocert.step.sm
clientConfig:
service:
name: autocert
namespace: step
path: "/mutate"
caBundle: $(cat $(step path)/certs/root_ca.crt | base64)
rules:
- operations: ["CREATE"]
apiGroups: [""]
apiVersions: ["v1"]
resources: ["pods"]
failurePolicy: Ignore
namespaceSelector:
matchLabels:
autocert.step.sm: enabled
EOF
```
### Check your work
If everything worked you should have CA and controller pods running in the `step` namespace and your webhook configuration should be installed:
```
$ kubectl -n step get pods
NAME READY STATUS RESTARTS AGE
ca-7577d7d667-vtfq5 1/1 Running 0 1m
controller-86bd99bd96-s9zlc 1/1 Running 0 28s
$ kubectl get mutatingwebhookconfiguration
NAME CREATED AT
autocert-webhook-config 2019-01-17T22:57:57Z
```