Policy as Code in Infrastructure as Code

Policy as Code is a modern approach that enables the enforcement of security and compliance policies in a programmatic way. By codifying policies, organizations can automate compliance checks, reduce manual errors, and ensure consistent application of security standards across their environments.

• **Infrastructure as Code (IaC)**: Managing infrastructure through code rather than manual processes.
• **Policy as Code**: Representing security and compliance policies in a machine-readable format.
• **Automated Compliance**: Automatically checking infrastructure against defined policies.
• **Declarative vs. Imperative Policies**: Declarative policies specify *what* the desired state is, while imperative policies specify *how* to achieve that state.

3.1 Define Policies

Start by defining the policies you want to enforce. This can include security best practices, compliance regulations, and organizational standards.

3.2 Choose a Policy Language

Choose a policy definition language such as Open Policy Agent (OPA) or HashiCorp Sentinel.

3.3 Write Policies

Write your policies in the chosen language. Here’s an example using OPA's Rego language:

                package kubernetes

                deny[{"error": msg}] {
                    input.kind == "Pod"
                    input.spec.containers[_].image == "example.com/bad-image"
                    msg = "Use of bad image is not allowed."
                }
                

3.4 Integrate with CI/CD

Integrate the policy checks into your CI/CD pipeline to ensure compliance before deployment.

3.5 Monitor and Update

Continuously monitor the environment and update policies as necessary to adapt to new threats or compliance requirements.

• Use descriptive names for policies to make them easily understandable.
• Version control your policy files alongside your code.
• Test policies in a staging environment before applying them in production.
• Ensure to have clear documentation for each policy.
• Regularly review and update policies to adapt to changing regulations and threats.