Configuring custom CRL and OCSP endpoints for issued certificates

Question

Pulumi · Accepted Answer

When managing certificates for secure communications, two essential components are the Certificate Revocation List (CRL) and Online Certificate Status Protocol (OCSP). These systems are used to check the revocation status of digital certificates, ensuring that communications are encrypted only with valid certificates.

To configure custom CRL and OCSP endpoints for issued certificates using Pulumi, you would typically be working with a Public Key Infrastructure (PKI) system. HashiCorp Vault is a common choice for managing PKI since it provides robust mechanisms for generating and managing the lifecycle of your certificates.

In the Pulumi program below, we will configure a Vault PKI secret backend with custom CRL and OCSP endpoints using Pulumi with the `vault` provider. We will create the necessary resources to set up the PKI backend, configure CRL distribution points, and specify OCSP server endpoints.

```typescript
import * as pulumi from "@pulumi/pulumi";
import * as vault from "@pulumi/vault";

// Creating a SecretBackendConfigUrls resource to specify CRL and OCSP endpoints.
const pkiSecretBackendConfigUrls = new vault.pkiSecret.SecretBackendConfigUrls("pkiConfigUrls", {
    backend: "pki", // Assume 'pki' is the path to your SecretBackend (mount point of your PKI backend).
    // Specify your CRL and OCSP endpoints here:
    crlDistributionPoints: ["http://crl.example.com/pki-crl"],
    ocspServers: ["http://ocsp.example.com"],
    // Issuing certificates endpoint (optional):
    issuingCertificates: ["http://certs.example.com/ca-certificates"],
});

// Creating a SecretBackendConfigCa resource if necessary to provide a bundled CA certificate and private key.
// It may not be needed if your CA certificate and private key are already set up in Vault.
const pkiSecretBackendConfigCa = new vault.pkiSecret.SecretBackendConfigCa("pkiConfigCa", {
    backend: "pki",
    pemBundle: `-----BEGIN CERTIFICATE-----
MIID...YOUR...CERTIFICATE...HERE
-----END CERTIFICATE-----
-----BEGIN RSA PRIVATE KEY-----
MIIE...YOUR...PRIVATE...KEY...HERE
-----END RSA PRIVATE KEY-----`,
});

// Export the endpoints to access later or output in the CLI.
export const crlEndpoint = pkiSecretBackendConfigUrls.crlDistributionPoints;
export const ocspEndpoint = pkiSecretBackendConfigUrls.ocspServers;
```

Let’s break down the code:

1. We import the required modules from `@pulumi/pulumi` to work with Pulumi and `@pulumi/vault` to work specifically with the Vault provider resources.
2. We declare a new `SecretBackendConfigUrls` resource named `pkiConfigUrls` using the Vault provider. This resource is configured to specify the URLs for the CRL distribution points and OCSP servers for your PKI setup.
3. The `backend` configuration is set to "pki", which should correspond to the path where your PKI secret backend is mounted in Vault. You will need to update this with the actual mount point of your PKI backend.
4. The `crlDistributionPoints` property is set to point to an example CRL endpoint that you would replace with your actual CRL distribution point URL.
5. The `ocspServers` property is set to point to an example OCSP responder endpoint that you would replace with your actual OCSP server URL.
6. We optionally specify the `issuingCertificates` endpoint, which you might use if you have an endpoint from which certificates issued by the CA can be downloaded.
7. We optionally create a `SecretBackendConfigCa` resource named `pkiConfigCa`, which is used to configure a CA certificate and private key if this has not yet been set up. Please replace the placeholder text with your actual certificate and private key.
8. We export the endpoints so they can be easily retrieved. These are the values that Pulumi will output once it has applied your infrastructure changes.

Before running this program, you'll need to ensure that your local environment is configured with the necessary Vault credentials to authenticate with your Vault instance. Also, make sure to replace the placeholder values for the CRL and OCSP endpoints with the actual URLs used in your infrastructure and provide your legitimate CA certificate and private key.

This Pulumi program provides a starting point for managing your PKI infrastructure as code, thus bringing the benefits of versioning, audit trails, and repeatability to your certificate issuance processes.