Kubewarden is a Kubernetes Dynamic Admission Controller that uses policies written in WebAssembly.

For more information refer to the official Kubewarden website.

Kubewarden Admission Controller - Monorepo

This repository is a monorepo containing the source code for all the different components of the Kubewarden Admission Controller:

• kubewarden-controller: A Kubernetes controller that allows you to dynamically register Kubewarden admission policies and reconcile them with the Kubernetes webhooks of the cluster where it's deployed
• policy-server: The runtime component that evaluates admission policies written in WebAssembly
• audit-scanner: A component that scans existing resources in the cluster against registered policies
• kwctl: A CLI tool for testing and managing Kubewarden policies

Documentation

The full and exhaustive documentation is available at docs.kubewarden.io.

The docs/ folder contains README files for each component:

• Controller
• Policy Server
• Audit Scanner
• kwctl
• CRDs

Installation

The kubewarden-controller can be deployed using a Helm chart. For instructions, see https://charts.kubewarden.io.

Please refer to our quickstart for more details.

Software bill of materials & provenance

All Kubewarden components has its software bill of materials (SBOM) and build Provenance information published every release. It follows the SPDX format and SLSA provenance schema. Both of the files are generated by Docker buildx during the build process and stored in the container registry together with the container image as well as upload in the release page.

You can find them together with the signature and certificate used to sign it in the release assets, and attached to the image as JSON-encoded documents following the in-toto SPDX predicate format. You can obtain them with crane or docker buildx imagetools inspect.

You can verify the container image with:

cosign verify-blob --certificate-oidc-issuer=https://token.actions.githubusercontent.com  \
    --certificate-identity="https://github.com/kubewarden/kubewarden-controller/.github/workflows/attestation.yml@<TAG TO VERIFY>" \
    --bundle kubewarden-controller-attestation-amd64-provenance.intoto.jsonl.bundle.sigstore \
    kubewarden-controller-attestation-amd64-provenance.intoto.jsonl

To verify the attestation manifest and its layer signatures:

cosign verify --certificate-oidc-issuer=https://token.actions.githubusercontent.com  \
    --certificate-identity="https://github.com/kubewarden/kubewarden-controller/.github/workflows/attestation.yml@<TAG TO VERIFY>" \
    ghcr.io/kubewarden/kubewarden-controller@sha256:1abc0944378d9f3ee2963123fe84d045248d320d76325f4c2d4eb201304d4c4e

Note

All the commands and file locations used in this section to validate the controller components can be used to verify all the others Kubewarden components as well.

That sha256 hash is the digest of the attestation manifest or its layers. Therefore, you need to find this hash in the registry using the UI or tools like crane. For example, the following command will show you all the attestation manifests of the latest tag:

crane manifest  ghcr.io/kubewarden/kubewarden-controller:latest | jq '.manifests[] | select(.annotations["vnd.docker.reference.type"]=="attestation-manifest")'
{
  "mediaType": "application/vnd.oci.image.manifest.v1+json",
  "digest": "sha256:fc01fa6c82cffeffd23b737c7e6b153357d1e499295818dad0c7d207f64e6ee8",
  "size": 1655,
  "annotations": {
    "vnd.docker.reference.digest": "sha256:611d499ec9a26034463f09fa4af4efe2856086252d233b38e3fc31b0b982d369",
    "vnd.docker.reference.type": "attestation-manifest"
  },
  "platform": {
    "architecture": "unknown",
    "os": "unknown"
  }
}
{
  "mediaType": "application/vnd.oci.image.manifest.v1+json",
  "digest": "sha256:e0cd736c2241407114256e09a4cdeef55eb81dcd374c5785c4e5c9362a0088a2",
  "size": 1655,
  "annotations": {
    "vnd.docker.reference.digest": "sha256:03e5db83a25ea2ac498cf81226ab8db8eb53a74a2c9102e4a1da922d5f68b70f",
    "vnd.docker.reference.type": "attestation-manifest"
  },
  "platform": {
    "architecture": "unknown",
    "os": "unknown"
  }
}

Then you can use the digest field to verify the attestation manifest and its layers signatures.

cosign verify --certificate-oidc-issuer=https://token.actions.githubusercontent.com  \
    --certificate-identity="https://github.com/kubewarden/kubewarden-controller/.github/workflows/attestation.yml@<TAG TO VERIFY>" \
    ghcr.io/kubewarden/kubewarden-controller@sha256:fc01fa6c82cffeffd23b737c7e6b153357d1e499295818dad0c7d207f64e6ee8

crane manifest  ghcr.io/kubewarden/kubewarden-controller@sha256:fc01fa6c82cffeffd23b737c7e6b153357d1e499295818dad0c7d207f64e6ee8
{
  "schemaVersion": 2,
  "mediaType": "application/vnd.oci.image.manifest.v1+json",
  "config": {
    "mediaType": "application/vnd.oci.image.config.v1+json",
    "digest": "sha256:eda788a0e94041a443eca7286a9ef7fce40aa2832263f7d76c597186f5887f6a",
    "size": 463
  },
  "layers": [
    {
      "mediaType": "application/vnd.in-toto+json",
      "digest": "sha256:563689cdee407ab514d057fe2f8f693189279e10bfe4f31f277e24dee00793ea",
      "size": 94849,
      "annotations": {
        "in-toto.io/predicate-type": "https://spdx.dev/Document"
      }
    },
    {
      "mediaType": "application/vnd.in-toto+json",
      "digest": "sha256:7ce0572628290373e17ba0bbb44a9ec3c94ba36034124931d322ca3fbfb768d9",
      "size": 7363045,
      "annotations": {
        "in-toto.io/predicate-type": "https://spdx.dev/Document"
      }
    },
    {
      "mediaType": "application/vnd.in-toto+json",
      "digest": "sha256:dacf511c5ec7fd87e8692bd08c3ced2c46f4da72e7271b82f1b3720d5b0a8877",
      "size": 71331,
      "annotations": {
        "in-toto.io/predicate-type": "https://spdx.dev/Document"
      }
    },
    {
      "mediaType": "application/vnd.in-toto+json",
      "digest": "sha256:594da3e8bd8c6ee2682b0db35857933f9558fd98ec092344a6c1e31398082f4d",
      "size": 980,
      "annotations": {
        "in-toto.io/predicate-type": "https://spdx.dev/Document"
      }
    },
    {
      "mediaType": "application/vnd.in-toto+json",
      "digest": "sha256:7738d8d506c6482aaaef1d22ed920468ffaf4975afd28f49bb50dba2c20bf2ca",
      "size": 13838,
      "annotations": {
        "in-toto.io/predicate-type": "https://slsa.dev/provenance/v0.2"
      }
    }
  ]
}

cosign verify --certificate-oidc-issuer=https://token.actions.githubusercontent.com  \
    --certificate-identity="https://github.com/kubewarden/kubewarden-controller/.github/workflows/attestation.yml@<TAG TO VERIFY>" \
    ghcr.io/kubewarden/kubewarden-controller@sha256:594da3e8bd8c6ee2682b0db35857933f9558fd98ec092344a6c1e31398082f4d

Note that each attestation manifest (for each architecture) has its own layers. Each layer is a different SBOM SPDX or provenance file generated by Docker Buildx during the multi stage build process. You can also use crane to download the attestation file:

crane blob ghcr.io/kubewarden/kubewarden-controller@sha256:7738d8d506c6482aaaef1d22ed920468ffaf4975afd28f49bb50dba2c20bf2ca

Security disclosure

See SECURITY.md on the kubewarden/community repo.

Changelog

See GitHub Releases content.