sign release images with cosign, embed SBOMs, attach SLSA provenance (#10983)

* feat: sign release images with cosign and attach SBOM + SLSA provenance Co-Authored-By: Claude Fable 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01W8mi68bMNUFwCge7xAqyky * fix: pin cosign-installer to exact version (no floating v4 tag exists) Co-Authored-By: Claude Fable 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01W8mi68bMNUFwCge7xAqyky * fix: embed SBOMs at build time via depot instead of rekor-bound cosign attest Co-Authored-By: Claude Fable 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01W8mi68bMNUFwCge7xAqyky * docs: latest/main tags are only signed until the next main push Co-Authored-By: Claude Fable 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01W8mi68bMNUFwCge7xAqyky * fix: gate signing on push events in cli/extra workflows, verify version tag Co-Authored-By: Claude Fable 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01W8mi68bMNUFwCge7xAqyky * fix: refuse tag-targeted dispatches in publish workflows, use GITHUB_REF env Co-Authored-By: Claude Fable 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01W8mi68bMNUFwCge7xAqyky --------- Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
2026-09-08 16:03:27 +00:00 · 2026-09-05 11:11:20 +00:00
parent 9f7908e262
commit a2417f6fb6
6 changed files with 238 additions and 2 deletions
@@ -0,0 +1,56 @@
+name: Sign image and attach provenance
+description: >
+  Keyless-signs a pushed image digest with cosign (index and per-arch
+  manifests) and records SLSA provenance as a GitHub artifact attestation
+  pushed to the registry. SBOMs are not generated here: the build step embeds
+  them as BuildKit attestation manifests (depot `sbom: true`), which the index
+  signature then covers. The calling job must already be logged in to the
+  registry and must have id-token: write, attestations: write and
+  packages: write permissions (write-all covers all three).
+inputs:
+  image:
+    description: "Fully-qualified image name without tag, e.g. ghcr.io/windmill-labs/windmill"
+    required: true
+  digest:
+    description: "Pushed manifest digest (sha256:...) from build-push-action"
+    required: true
+runs:
+  using: composite
+  steps:
+    - name: Preflight
+      shell: bash
+      env:
+        DIGEST: ${{ inputs.digest }}
+      run: |
+        if [ -z "${ACTIONS_ID_TOKEN_REQUEST_URL:-}" ]; then
+          echo "::error::No OIDC token available; the calling job needs id-token: write"
+          exit 1
+        fi
+        case "$DIGEST" in
+          sha256:*) ;;
+          *)
+            echo "::error::digest '$DIGEST' is not a sha256: digest"
+            exit 1
+            ;;
+        esac
+
+    # cosign v2 writes the classic sha256-<digest>.sig tag format that the
+    # installed base of cosign clients can verify; v3's bundle format cannot be
+    # verified by v2 clients yet, so stay on v2 until v3 verification is common.
+    - uses: sigstore/cosign-installer@v4.1.2
+      with:
+        cosign-release: "v2.6.5"
+
+    - name: Cosign keyless sign (index + per-arch manifests)
+      shell: bash
+      env:
+        IMAGE: ${{ inputs.image }}
+        DIGEST: ${{ inputs.digest }}
+      run: cosign sign --yes --recursive "${IMAGE}@${DIGEST}"
+
+    - name: SLSA provenance (GitHub artifact attestation)
+      uses: actions/attest-build-provenance@v4
+      with:
+        subject-name: ${{ inputs.image }}
+        subject-digest: ${{ inputs.digest }}
+        push-to-registry: true
@@ -13,9 +13,13 @@ permissions:
  contents: read
  id-token: write
  packages: write
+  attestations: write

 jobs:
  publish_cli:
+    # a tag-targeted dispatch would republish the release tags unsigned,
+    # un-verifying the release; to republish a release, re-push its tag
+    if: github.event_name == 'push' || !startsWith(github.ref, 'refs/tags/')
    runs-on: ubicloud
    steps:
      - uses: actions/checkout@v4
@@ -42,14 +46,23 @@ jobs:
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Build and push publicly
+        id: docker_build
        uses: depot/build-push-action@v1
        with:
          file: "./docker/DockerfileCli"
          platforms: linux/amd64,linux/arm64
          push: true
+          sbom: ${{ startsWith(github.ref, 'refs/tags/v') && github.event_name == 'push' }}
          tags: |
            ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}:latest
            ${{ steps.meta.outputs.tags }}
          labels: |
            ${{ steps.meta.outputs.labels }}
            org.opencontainers.image.licenses=AGPLv3
+
+      - name: Sign and attest release image
+        if: startsWith(github.ref, 'refs/tags/v') && github.event_name == 'push'
+        uses: ./.github/actions/sign-attest-image
+        with:
+          image: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
+          digest: ${{ steps.docker_build.outputs.digest }}
@@ -86,11 +86,13 @@ jobs:
            type=semver,pattern={{major}}.{{minor}}

      - name: Build and push publicly
+        id: docker_build
        uses: depot/build-push-action@v1
        with:
          context: .
          platforms: linux/amd64,linux/arm64
          push: true
+          sbom: ${{ startsWith(github.ref, 'refs/tags/v') && github.event_name == 'push' }}
          build-args: |
            features=ce
            WM_BUILD_VERSION=${{ github.sha }}
@@ -100,6 +102,13 @@ jobs:
          labels: |
            ${{ steps.meta-public.outputs.labels }}

+      - name: Sign and attest release image
+        if: startsWith(github.ref, 'refs/tags/v') && github.event_name == 'push'
+        uses: ./.github/actions/sign-attest-image
+        with:
+          image: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
+          digest: ${{ steps.docker_build.outputs.digest }}
+
  build_ee:
    runs-on: ubicloud
    if: (github.event_name != 'workflow_dispatch') || github.event.inputs.ee
@@ -149,11 +158,13 @@ jobs:
          ./backend/substitute_ee_code.sh --copy --dir ./windmill-ee-private

      - name: Build and push publicly ee
+        id: docker_build
        uses: depot/build-push-action@v1
        with:
          context: .
          platforms: linux/amd64,linux/arm64
          push: true
+          sbom: ${{ startsWith(github.ref, 'refs/tags/v') && github.event_name == 'push' }}
          build-args: |
            features=ee
            WM_BUILD_VERSION=${{ github.sha }}
@@ -164,6 +175,13 @@ jobs:
            ${{ steps.meta-ee-public.outputs.labels }}
            org.opencontainers.image.licenses=Windmill-Enterprise-License

+      - name: Sign and attest release image
+        if: startsWith(github.ref, 'refs/tags/v') && github.event_name == 'push'
+        uses: ./.github/actions/sign-attest-image
+        with:
+          image: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}-ee
+          digest: ${{ steps.docker_build.outputs.digest }}
+
  attach_amd64_binary_to_release:
    needs: [build, build_ee]
    runs-on: ubicloud
@@ -358,6 +376,21 @@ jobs:
          docker buildx imagetools create ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}:${{ env.DEV_SHA }} --tag ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}:latest
          docker buildx imagetools create ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}:${{ env.DEV_SHA }} --tag ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}:main

+      - uses: sigstore/cosign-installer@v4.1.2
+        if: startsWith(github.ref, 'refs/tags/v')
+        with:
+          cosign-release: "v2.6.5"
+      # end-to-end release guard: the version tag pushed by this run must
+      # verify against this exact run's identity (the mutable :latest/:dev
+      # tags race with concurrent main builds, so they are not asserted here)
+      - name: Verify release image is signed
+        if: startsWith(github.ref, 'refs/tags/v')
+        run: |
+          cosign verify \
+            --certificate-oidc-issuer https://token.actions.githubusercontent.com \
+            --certificate-identity "https://github.com/windmill-labs/windmill/.github/workflows/docker-image.yml@${GITHUB_REF}" \
+            "${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}:${GITHUB_REF_NAME#v}"
+
  tag_latest_ee:
    runs-on: ubicloud
    needs: [run_integration_test, build_ee]
@@ -379,6 +412,21 @@ jobs:
          docker buildx imagetools create ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}-ee:${{ env.DEV_SHA }} --tag ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}-ee:latest
          docker buildx imagetools create ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}-ee:${{ env.DEV_SHA }} --tag ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}-ee:main

+      - uses: sigstore/cosign-installer@v4.1.2
+        if: startsWith(github.ref, 'refs/tags/v')
+        with:
+          cosign-release: "v2.6.5"
+      # end-to-end release guard: the version tag pushed by this run must
+      # verify against this exact run's identity (the mutable :latest/:dev
+      # tags race with concurrent main builds, so they are not asserted here)
+      - name: Verify release ee image is signed
+        if: startsWith(github.ref, 'refs/tags/v')
+        run: |
+          cosign verify \
+            --certificate-oidc-issuer https://token.actions.githubusercontent.com \
+            --certificate-identity "https://github.com/windmill-labs/windmill/.github/workflows/docker-image.yml@${GITHUB_REF}" \
+            "${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}-ee:${GITHUB_REF_NAME#v}"
+
  verify_ee_image_vulnerabilities:
    runs-on: ubicloud
    needs: [tag_latest_ee]
@@ -493,11 +541,13 @@ jobs:
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Build and push publicly ee
+        id: docker_build
        uses: depot/build-push-action@v1
        with:
          context: .
          platforms: linux/amd64
          push: true
+          sbom: ${{ startsWith(github.ref, 'refs/tags/v') && github.event_name == 'push' }}
          file: "./docker/DockerfileCuda"
          tags: |
            ${{ steps.meta-ee-public.outputs.tags }}
@@ -505,6 +555,13 @@ jobs:
            ${{ steps.meta-ee-public.outputs.labels }}
            org.opencontainers.image.licenses=Windmill-Enterprise-License

+      - name: Sign and attest release image
+        if: startsWith(github.ref, 'refs/tags/v') && github.event_name == 'push'
+        uses: ./.github/actions/sign-attest-image
+        with:
+          image: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}-ee-cuda
+          digest: ${{ steps.docker_build.outputs.digest }}
+
  build_slim:
    if: ${{ startsWith(github.ref, 'refs/tags/v') }}
    needs: [build]
@@ -537,17 +594,26 @@ jobs:
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Build and push publicly ee
+        id: docker_build
        uses: depot/build-push-action@v1
        with:
          context: .
          platforms: linux/amd64
          push: true
+          sbom: ${{ startsWith(github.ref, 'refs/tags/v') && github.event_name == 'push' }}
          file: "./docker/DockerfileSlim"
          tags: |
            ${{ steps.meta-ee-public.outputs.tags }}
          labels: |
            ${{ steps.meta-ee-public.outputs.labels }}

+      - name: Sign and attest release image
+        if: startsWith(github.ref, 'refs/tags/v') && github.event_name == 'push'
+        uses: ./.github/actions/sign-attest-image
+        with:
+          image: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}-slim
+          digest: ${{ steps.docker_build.outputs.digest }}
+
  build_ee_slim:
    needs: [build_ee]
    runs-on: ubicloud
@@ -582,11 +648,13 @@ jobs:
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Build and push publicly ee
+        id: docker_build
        uses: depot/build-push-action@v1
        with:
          context: .
          platforms: linux/amd64,linux/arm64
          push: true
+          sbom: ${{ startsWith(github.ref, 'refs/tags/v') && github.event_name == 'push' }}
          file: "./docker/DockerfileSlimEe"
          tags: |
            ${{ steps.meta-ee-public.outputs.tags }}
@@ -594,6 +662,13 @@ jobs:
            ${{ steps.meta-ee-public.outputs.labels }}
            org.opencontainers.image.licenses=Windmill-Enterprise-License

+      - name: Sign and attest release image
+        if: startsWith(github.ref, 'refs/tags/v') && github.event_name == 'push'
+        uses: ./.github/actions/sign-attest-image
+        with:
+          image: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}-ee-slim
+          digest: ${{ steps.docker_build.outputs.digest }}
+
  build_full:
    if: ${{ startsWith(github.ref, 'refs/tags/v') }}
    needs: [build]
@@ -626,17 +701,26 @@ jobs:
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Build and push publicly
+        id: docker_build
        uses: depot/build-push-action@v1
        with:
          context: .
          platforms: linux/amd64,linux/arm64
          push: true
+          sbom: ${{ startsWith(github.ref, 'refs/tags/v') && github.event_name == 'push' }}
          file: "./docker/DockerfileFull"
          tags: |
            ${{ steps.meta-public.outputs.tags }}
          labels: |
            ${{ steps.meta-public.outputs.labels }}

+      - name: Sign and attest release image
+        if: startsWith(github.ref, 'refs/tags/v') && github.event_name == 'push'
+        uses: ./.github/actions/sign-attest-image
+        with:
+          image: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}-full
+          digest: ${{ steps.docker_build.outputs.digest }}
+
  build_ee_full:
    if: ${{ startsWith(github.ref, 'refs/tags/v') }}
    needs: [build_ee]
@@ -669,14 +753,23 @@ jobs:
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Build and push publicly ee
+        id: docker_build
        uses: depot/build-push-action@v1
        with:
          context: .
          platforms: linux/amd64,linux/arm64
          push: true
+          sbom: ${{ startsWith(github.ref, 'refs/tags/v') && github.event_name == 'push' }}
          file: "./docker/DockerfileFullEe"
          tags: |
            ${{ steps.meta-ee-public.outputs.tags }}
          labels: |
            ${{ steps.meta-ee-public.outputs.labels }}
            org.opencontainers.image.licenses=Windmill-Enterprise-License
+
+      - name: Sign and attest release image
+        if: startsWith(github.ref, 'refs/tags/v') && github.event_name == 'push'
+        uses: ./.github/actions/sign-attest-image
+        with:
+          image: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}-ee-full
+          digest: ${{ steps.docker_build.outputs.digest }}
@@ -84,6 +84,9 @@ jobs:

  publish_extra:
    needs: [sleep, test_extra]
+    # a tag-targeted dispatch would republish the release tags unsigned,
+    # un-verifying the release; to republish a release, re-push its tag
+    if: github.event_name == 'push' || !startsWith(github.ref, 'refs/tags/')
    runs-on: ubicloud-standard-8
    steps:
      - uses: actions/checkout@v4
@@ -112,15 +115,24 @@ jobs:
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Build and push publicly
+        id: docker_build
        uses: depot/build-push-action@v1
        with:
          context: .
          file: ./docker/DockerfileExtra
          platforms: linux/amd64,linux/arm64
          push: true
+          sbom: ${{ startsWith(github.ref, 'refs/tags/v') && github.event_name == 'push' }}
          tags: |
            ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}:latest
            ${{ steps.meta.outputs.tags }}
          labels: |
            ${{ steps.meta.outputs.labels }}
            org.opencontainers.image.licenses=AGPLv3
+
+      - name: Sign and attest release image
+        if: startsWith(github.ref, 'refs/tags/v') && github.event_name == 'push'
+        uses: ./.github/actions/sign-attest-image
+        with:
+          image: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
+          digest: ${{ steps.docker_build.outputs.digest }}