cert-manager-webhook-ns1

NS1 Webhook for Cert Manager

This project is in MAINTENANCE mode

This is a webhook solver for NS1, for use with cert-manager, to solve ACME DNS01 challenges.

Tested with kubernetes v1.15.7, v1.16.2, and v1.17.0

Prerequisites

helm, for installing charts.

Tested with helm v2.16.1 and v3.0.3

certmanager, the underlying framework this project plugs into.

Tested with cert-manager v0.13.0 and v1.0.3

Installation

1. Install the chart with helm

We have a helm repo set up, so you can use that, or you can install directly from source:

$ helm install --namespace cert-manager cert-manager-webhook-ns1 ./deploy/cert-manager-webhook-ns1

1. Populate a secret with your NS1 API Key

$ kubectl --namespace cert-manager create secret generic ns1-credentials --from-literal=apiKey='Your NS1 API Key'

1. We need to grant permission for service account to get the secret. Copy the following and apply with something like:

$ kubectl --namespace cert-manager apply -f secret_reader.yaml

Note that it may make more sense in your setup to use a ClusterRole and ClusterRoleBinding here.

apiVersion: rbac.authorization.k8s.io/v1
kind: Role
metadata:
  name: cert-manager-webhook-ns1:secret-reader
rules:
- apiGroups: [""]
  resources: ["secrets"]
  resourceNames: ["ns1-credentials"]
  verbs: ["get", "watch"]
---
apiVersion: rbac.authorization.k8s.io/v1
kind: RoleBinding
metadata:
  name: cert-manager-webhook-ns1:secret-reader
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: Role
  name: cert-manager-webhook-ns1:secret-reader
subjects:
  - apiGroup: ""
    kind: ServiceAccount
    name: cert-manager-webhook-ns1

Configuration

You'll need to edit and apply some resources, with something like:

$ kubectl --namespace cert-manager apply -f my_resource.yaml

Note that we use the cert-manager namespace, but it may make more sense in your setup to hame more nuanced namespace management.

1. Create Issuer(s), we'll use letsencrypt for example. We'll use ClusterIssuer here, which will be available accross namespaces. You may prefer to use Issuer. This is where NS1 API options are set (endpoint, ignoreSSL).

Staging issuer (optional):

apiVersion: cert-manager.io/v1
kind: ClusterIssuer
metadata:
  name: letsencrypt-staging
spec:
  acme:
    # The ACME server URL
    server: https://acme-staging-v02.api.letsencrypt.org/directory

    # Email address used for ACME registration
    email: user@example.com # REPLACE THIS WITH YOUR EMAIL!!!

    # Name of a secret used to store the ACME account private key
    privateKeySecretRef:
      name: letsencrypt-staging

    solvers:
    - dns01:
        webhook:
          groupName: acme.nsone.net
          solverName: ns1
          config:
            apiKeySecretRef:
              key: apiKey
              name: ns1-credentials
            # Replace this with your NS1 API endpoint if not using "managed"
            endpoint: "https://api.nsone.net/v1/"
            ignoreSSL: false

Production issuer:

apiVersion: cert-manager.io/v1
kind: ClusterIssuer
metadata:
  name: letsencrypt-prod
spec:
  acme:
    # The ACME server URL
    server: https://acme-v02.api.letsencrypt.org/directory

    # Email address used for ACME registration
    email: user@example.com # REPLACE THIS WITH YOUR EMAIL!!!

    # Name of a secret used to store the ACME account private key
    privateKeySecretRef:
      name: letsencrypt-prod

    solvers:
    - dns01:
        webhook:
          groupName: acme.nsone.net
          solverName: ns1
          config:
            apiKeySecretRef:
              key: apiKey
              name: ns1-credentials
            # Replace this with your NS1 API endpoint if not using "managed"
            endpoint: "https://api.nsone.net/v1/"
            ignoreSSL: false

1. Test things by issuing a certificate. This example requests a cert for example.com from the staging issuer, default namespace should be fine:

apiVersion: cert-manager.io/v1
kind: Certificate
metadata:
  name: example.com
spec:
  commonName: example.com
  dnsNames:
  - example.com
  issuerRef:
    name: letsencrypt-staging
  secretName: example-com-tls

After a minute or two, the Certificate should show as Ready. If not, you can follow the resource chain from Certificate to CertificateRequest and on down until you see a useful error message.

Automatically creating Certificates for Ingress resources

See cert-manager docs on "ingress shims".

The gist of it is adding an annotation, and a tls section to your Ingress definition. A simple ingress example is below with pertinent areas bolded. We use the ingress-nginx ingress controller, but it should be the same idea for any ingress.

You do of course, need to set up an A Record in NS1 connecting the domain to the external IP of the ingress controller's LoadBalancer service. In the example below the domain would be my-app.example.com.

apiVersion: networking.k8s.io/v1beta1
kind: Ingress
metadata:
  name: my-ingress
  annotations:
    kubernetes.io/ingress.class: "nginx"
    cert-manager.io/cluster-issuer: "letsencrypt-prod" # sets the issuer to use
spec:
  rules:
  - host: my-app.example.com
    http:
      paths:
      - backend:
          serviceName: my-app-service
          servicePort: 80
  tls:
  - hosts:
    - my-app.example.com   # domain name(s) for the certificate
    secretName: my-app-tls # where to store the secret

Troubleshooting

If things aren't working, check the logs in the main cert-manager pod first, they are pretty communicative. Check logs from the other cert-manager-* pods and the cert-manager-webhook-ns1 pod.

If you've generated a Certificate but no CertificateRequest is generated, the main cert-manager pod logs should show why any action was skipped.

Since this project is essentially a plugin to cert-manager, detailed docs mainly live in the cert-manager project. Here are some specific docs that may be helpful:

• About ACME
• About DNS01 Challenges
• Troubleshooting Issuing ACME Certificates
• Securing Ingress Resources

Development

Running the test suite

All DNS providers must run the DNS01 provider conformance testing suite, else they will have undetermined behaviour when used with cert-manager.

It is essential that you configure and run the test suite when creating or modifying a DNS01 webhook.

The tests are "live" and require a functioning, DNS-accessible zone, as well as credentials for the NS1 API. The tests will create (and remove) a TXT record for the test zone.

1. Prepare testing environment by running the fetch-test-binaries script:

$ scripts/fetch-test-binaries.sh

1. See the README in testdata/ns1 and copy/edit the files as needed.

2. Run the tests with TEST_ZONE_NAME set to your live, NS1-controlled zone:

$ TEST_ZONE_NAME=example.com. go test .

Maintaining the Docker image and Helm repository

See Makefile for commands to build and push the Docker image, and to maintain the Helm repo.

Contributions

Pull Requests and issues are welcome. See the NS1 Contribution Guidelines for more information.