Rotating CloudFront Key Group keys for enhanced security

Question

Pulumi · Accepted Answer

Rotating keys for a CloudFront Key Group is a best practice for enhancing security by limiting the lifespan of keys and thus reducing the potential for abuse if they were to be compromised. To rotate these keys, you typically remove the current keys from the key group and add new ones. It's important to first ensure that you have new keys ready to replace the old ones to avoid service disruption.

In Pulumi, you can manage AWS resources using the AWS provider, which enables you to define infrastructure as code using programming languages like TypeScript. Below, I'm going to guide you through a Pulumi program that rotates the keys in a CloudFront Key Group.

The program will:
1. Define a new CloudFront Key Group.
2. Rotate the keys by replacing them with a new set.

To perform a rotation, you typically need to have a new key ready or create a new one before removing the old key to ensure that there is always a valid key in the Key Group during the process.

Please ensure you've set up your AWS credentials correctly and have installed Pulumi on your machine before running this program.

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

// A new set of public keys can be added to the CloudFront Key Group to rotate the keys.
// First, create the public key infrastructure. In a production setting, these would likely be imported or generated differently.
const publicKey1 = new aws.cloudfront.PublicKey("my-public-key-1", {
    encodedKey: `-----BEGIN PUBLIC KEY-----
...
-----END PUBLIC KEY-----`,
    // Provide a unique name for the public key
    name: "my-public-key-1",
});

const publicKey2 = new aws.cloudfront.PublicKey("my-public-key-2", {
    encodedKey: `-----BEGIN PUBLIC KEY-----
...
-----END PUBLIC KEY-----`,
    // Provide a unique name for the public key
    name: "my-public-key-2",
});

// Then, define a CloudFront Key Group with the new public keys.
const keyGroup = new aws.cloudfront.KeyGroup("my-key-group", {
    items: [publicKey1.id, publicKey2.id],
    // Provide a unique name for the key group
    name: "my-key-group",
});

// Export the Key Group ID and the key IDs.
export const keyGroupId = keyGroup.id;
export const publicKeyIds = [publicKey1.id, publicKey2.id];

// Instead of creating new keys, in practice, you might be adding existing key IDs to the group.
// To remove an old key, simply update the `items` array by removing the old key ID.

// Note: This code assumes that you have valid public key material to include in the `encodedKey` field.
// The `encodedKey` field content is shortened for brevity and should be replaced with the actual public key content.

```

This code will perform the following actions:
- Import the necessary Pulumi and AWS SDK libraries.
- Create two new public keys. In reality, these would be created ahead of time, and their IDs would be inserted into the code (they are represented with placeholders in the example).
- Add these public keys to a new Key Group so that they can be used with CloudFront distributions. The Key Group is named `my-key-group` and it references the public keys by their Pulumi-generated IDs (`publicKey1.id` and `publicKey2.id`).

After running this program, the output will show the IDs of the newly created Key Group and the public keys, which you can use to reference in other parts of your CloudFront distribution configurations.

Remember, when you update the content of a Pulumi stack, such as adding or removing keys from a Key Group, Pulumi calculates the differences and applies only the necessary changes. When you need to remove old keys, you would update the `keyGroup` resource's `items` array to exclude the IDs of the keys you're rotating out.

Please replace the `encodedKey` placeholder values with your actual public key content when using this code and ensure to handle secrets appropriately in a production environment.

To execute this Pulumi program, save the code in a file named `index.ts`, then run `pulumi up` from your command line in the same directory. Pulumi will then perform the deployment and output the Key Group and public key IDs.