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Trying Pinniped

Prerequisites

A Kubernetes cluster of a type supported by Pinniped. Currently, Pinniped supports self-hosted clusters where the Kube Controller Manager pod is accessible from Pinniped's pods. Support for other types of Kubernetes distributions is coming soon.

Don't have a cluster handy? Consider using kind on your local machine. See below for an example of using kind.
A kubeconfig where the current context points to that cluster and has admin-like privileges on that cluster.

Don't have an identity provider of a type supported by Pinniped handy? Start by installing local-user-authenticator on the same cluster where you would like to try Pinniped by following the directions in deploy-local-user-authenticator/README.md. See below for an example of deploying this on kind.

Steps

General Steps

Install Pinniped by following the directions in deploy/README.md.
Download the Pinniped CLI from Pinniped's github Releases page.
Generate a kubeconfig using the Pinniped CLI. Run pinniped get-kubeconfig --help for more information.
Run kubectl commands using the generated kubeconfig to authenticate using Pinniped during those commands.

Specific Example of Deploying on kind Using `local-user-authenticator` as the Identity Provider

Install the tools required for the following steps.
- This example deployment uses ytt and kapp from Carvel to template the YAML files and to deploy the app. Either install ytt and kapp or use the container image from Dockerhub. E.g. brew install k14s/tap/ytt k14s/tap/kapp on a Mac.
- Install kind, if not already installed. e.g. brew install kind on a Mac.
- kind depends on Docker. If not already installed, install Docker, e.g. brew cask install docker on a Mac.
- This demo requires kubectl, which comes with Docker, or can be installed separately.
- This demo requires a tool capable of generating a bcrypt hash in order to interact with the webhook. The example below uses htpasswd, which is installed on most macOS systems, and can be installed on some Linux systems via the apache2-utils package (e.g., apt-get install apache2-utils).
Create a new Kubernetes cluster using kind create cluster. Optionally provide a cluster name using the --name flag. kind will automatically update your kubeconfig to point to the new cluster.

Clone this repo.

git clone https://github.com/vmware-tanzu/pinniped.git /tmp/pinniped --depth 1

Deploy the local-user-authenticator app:

cd /tmp/pinniped/deploy-local-user-authenticator
ytt --file . | kapp deploy --yes --app local-user-authenticator --diff-changes --file -

Create a test user.

kubectl create secret generic pinny-the-seal \
  --namespace local-user-authenticator \
  --from-literal=groups=group1,group2 \
  --from-literal=passwordHash=$(htpasswd -nbBC 10 x password123 | sed -e "s/^x://")

Fetch the auto-generated CA bundle for the local-user-authenticator's HTTP TLS endpoint.

kubectl get secret local-user-authenticator-tls-serving-certificate --namespace local-user-authenticator \
  -o jsonpath={.data.caCertificate} \
  | tee /tmp/local-user-authenticator-ca-base64-encoded

Deploy Pinniped.

 cd /tmp/pinniped/deploy
 ytt --file . | kapp deploy --yes --app pinniped --diff-changes --file -

Create a WebhookIdentityProvider object to configure Pinniped to authenticate using local-user-authenticator

cat <<EOF | kubectl create --namespace pinniped -f -
apiVersion: idp.pinniped.dev/v1alpha1
kind: WebhookIdentityProvider
metadata:
  name: local-user-authenticator
spec:
  endpoint: https://local-user-authenticator.local-user-authenticator.svc/authenticate
  tls:
    certificateAuthorityData: $(cat /tmp/local-user-authenticator-ca-base64-encoded)
EOF

Download the latest version of the Pinniped CLI binary for your platform from Pinniped's github Releases page.
Move the Pinniped CLI binary to your preferred directory and add the executable bit, e.g. chmod +x /usr/local/bin/pinniped.
Generate a kubeconfig for the current cluster. Use --token to include a token which should allow you to authenticate as the user that you created above.
```
pinniped get-kubeconfig --token "pinny-the-seal:password123" --idp-type webhook --idp-name local-user-authenticator > /tmp/pinniped-kubeconfig
```
Note that the above command will print a warning to the screen. You can ignore this warning. Pinniped tries to auto-discover the URL for the Kubernetes API server, but it is not able to do so on kind clusters. The warning is just letting you know that the Pinniped CLI decided to ignore the auto-discovery URL and instead use the URL from your existing kubeconfig.
Try using the generated kubeconfig to issue arbitrary kubectl commands as the pinny-the-seal user.
```
kubectl --kubeconfig /tmp/pinniped-kubeconfig get pods -n pinniped
```
Because this user has no RBAC permissions on this cluster, the previous command results in the error Error from server (Forbidden): pods is forbidden: User "pinny-the-seal" cannot list resource "pods" in API group "" in the namespace "pinniped". However, this does prove that you are authenticated and acting as the "pinny-the-seal" user.
Create RBAC rules for the test user to give them permissions to perform actions on the cluster. For example, grant the test user permission to view all cluster resources.
```
kubectl create clusterrolebinding pinny-can-read --clusterrole view --user pinny-the-seal
```
Use the generated kubeconfig to issue arbitrary kubectl commands as the pinny-the-seal user.
```
kubectl --kubeconfig /tmp/pinniped-kubeconfig get pods -n pinniped
```
The user has permission to list pods, so the command succeeds! 🎉

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