Verify Image

Using the Cosign project, OCI images may be signed to ensure supply chain security is maintained. Those signatures can be verified before pulling into a cluster. This policy checks the signature of an image repo called ghcr.io/kyverno/test-verify-image to ensure it has been signed by verifying its signature against the provided public key. This policy serves as an illustration for how to configure a similar rule and will require replacing with your image(s) and keys.

Policy Definition

/other/verify_image.yaml

 1apiVersion: kyverno.io/v1
 2kind: ClusterPolicy
 3metadata:
 4  name: verify-image
 5  annotations:
 6    policies.kyverno.io/title: Verify Image
 7    policies.kyverno.io/category: Sample
 8    policies.kyverno.io/severity: medium
 9    policies.kyverno.io/subject: Pod
10    policies.kyverno.io/minversion: 1.4.2
11    policies.kyverno.io/description: >-
12      Using the Cosign project, OCI images may be signed to ensure supply chain
13      security is maintained. Those signatures can be verified before pulling into
14      a cluster. This policy checks the signature of an image repo called
15      ghcr.io/kyverno/test-verify-image to ensure it has been signed by verifying
16      its signature against the provided public key. This policy serves as an illustration for
17      how to configure a similar rule and will require replacing with your image(s) and keys.      
18spec:
19  validationFailureAction: enforce
20  background: false
21  rules:
22    - name: verify-image
23      match:
24        resources:
25          kinds:
26            - Pod
27      verifyImages:
28      - image: "ghcr.io/kyverno/test-verify-image:*"
29        key: |-
30          -----BEGIN PUBLIC KEY-----
31          MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAE8nXRh950IZbRj8Ra/N9sbqOPZrfM
32          5/KAQN0/KjHcorm/J5yctVd7iEcnessRQjU917hmKO6JWVGHpDguIyakZA==
33          -----END PUBLIC KEY-----

Create policy issue