sbom signing (#303)

Signed-off-by: Fabian Kammel <fk@edgeless.systems>

.github/actions/build_micro_service/action.yml

@@ -17,6 +17,15 @@ inputs:
   githubToken:
     description: "GitHub authorization token"
     required: true
+  cosignPublicKey:
+    description: "Cosign public key"
+    required: false
+  cosignPrivateKey:
+    description: "Cosign private key"
+    required: false
+  cosignPassword:
+    description: "Password for Cosign private key"
+    required: false
 
 # Linux runner only (Docker required)
 runs:
@@ -56,3 +65,12 @@ runs:
         tags: ${{ steps.meta.outputs.tags }}
         build-args: |
           PROJECT_VERSION=${{ inputs.projectVersion }}
+
+    - name: Generate SBOM
+      uses: ./.github/actions/container_sbom
+      with:
+        containerReference: ghcr.io/${{ github.repository }}/${{ inputs.name }}@${{ steps.build-micro-service.outputs.digest }}
+        cosignPublicKey: ${{ inputs.cosignPublicKey }}
+        cosignPrivateKey: ${{ inputs.cosignPrivateKey }}
+        cosignPassword: ${{ inputs.cosignPassword }}
+      if: ${{ inputs.cosignPublicKey != '' && inputs.cosignPrivateKey != '' && inputs.cosignPassword != '' }}

.github/actions/build_operator/action.yml

@@ -13,6 +13,15 @@ inputs:
   githubToken:
     description: "GitHub authorization token"
     required: true
+  cosignPublicKey:
+    description: "Cosign public key"
+    required: false
+  cosignPrivateKey:
+    description: "Cosign private key"
+    required: false
+  cosignPassword:
+    description: "Password for Cosign private key"
+    required: false
 
 # Linux runner only (Docker required)
 runs:
@@ -48,6 +57,7 @@ runs:
           type=ref,event=branch
 
     - name: Build and push container image
+      id: build-image
       uses: docker/build-push-action@c56af957549030174b10d6867f20e78cfd7debc5 # tag=v3.2.0
       with:
         context: ${{ inputs.sourceDir }}
@@ -55,6 +65,15 @@ runs:
         push: true
         tags: ${{ steps.meta.outputs.tags }}
 
+    - name: Generate SBOM
+      uses: ./.github/actions/container_sbom
+      with:
+        containerReference: ghcr.io/${{ github.repository }}/${{ inputs.name }}@${{ steps.build-image.outputs.digest }}
+        cosignPublicKey: ${{ inputs.cosignPublicKey }}
+        cosignPrivateKey: ${{ inputs.cosignPrivateKey }}
+        cosignPassword: ${{ inputs.cosignPassword }}
+      if: ${{ inputs.cosignPublicKey != '' && inputs.cosignPrivateKey != '' && inputs.cosignPassword != '' }}
+
     - name: Bundle for pseudo version
       if: ${{ steps.pseudo-version.outputs.pseudoVersion != '' && inputs.pushTag == '' }}
       shell: bash
@@ -84,6 +103,7 @@ runs:
           type=ref,event=branch
 
     - name: Build and push bundle image
+      id: build-image-bundle
       uses: docker/build-push-action@c56af957549030174b10d6867f20e78cfd7debc5 # tag=v3.2.0
       with:
         context: ${{ inputs.sourceDir }}
@@ -91,6 +111,16 @@ runs:
         push: true
         tags: ${{ steps.bundle-meta.outputs.tags }}
 
+    - name: Generate Bundle SBOM
+      uses: ./.github/actions/container_sbom
+      with:
+        containerReference: ghcr.io/${{ github.repository }}/${{ inputs.name }}-bundle@${{ steps.build-image-bundle.outputs.digest }}
+        cosignPublicKey: ${{ inputs.cosignPublicKey }}
+        cosignPrivateKey: ${{ inputs.cosignPrivateKey }}
+        cosignPassword: ${{ inputs.cosignPassword }}
+      if: ${{ inputs.cosignPublicKey != '' && inputs.cosignPrivateKey != '' && inputs.cosignPassword != '' }}
+
+
     - name: Build and push catalog for pseudo versions
       if: ${{ steps.pseudo-version.outputs.pseudoVersion != '' && inputs.pushTag == '' }}
       shell: bash

.github/actions/container_sbom/action.yml

@@ -0,0 +1,51 @@
+name: Container SBOM
+description: Create, vuln-check, sign and upload SBOMs for container images.
+inputs:
+  containerReference:
+    description: "Full reference to container image, e.g., ghcr.io/org/repo/img:tag"
+    required: true
+  cosignPublicKey:
+    description: "Cosign public key"
+    required: true
+  cosignPrivateKey:
+    description: "Cosign private key"
+    required: true
+  cosignPassword:
+    description: "Password for Cosign private key"
+    required: true
+
+runs:
+  using: "composite"
+  steps:
+    - name: Install Cosign
+      uses: sigstore/cosign-installer@7cc35d7fdbe70d4278a0c96779081e6fac665f88 # tag=v2.8.0
+      if: ${{ inputs.cosignPublicKey != '' && inputs.cosignPrivateKey != '' && inputs.cosignPassword != '' }}
+    - name: Download syft & grype
+      run: |
+        SYFT_VERSION=0.59.0
+        GRYPE_VERSION=0.51.0
+        curl -LO https://github.com/anchore/syft/releases/download/v${SYFT_VERSION}/syft_${SYFT_VERSION}_linux_amd64.tar.gz
+        tar -xzf syft_${SYFT_VERSION}_linux_amd64.tar.gz
+        ./syft version
+        curl -LO https://github.com/anchore/grype/releases/download/v${GRYPE_VERSION}/grype_${GRYPE_VERSION}_linux_amd64.tar.gz
+        tar -xzf grype_${GRYPE_VERSION}_linux_amd64.tar.gz
+        ./grype version
+        echo $(pwd) >> $GITHUB_PATH
+      shell: bash
+
+    - name: Generate SBOM
+      run: |
+        set -ex
+        echo "$COSIGN_PRIVATE_KEY" > cosign.key
+        syft attest --key cosign.key ${{ inputs.containerReference }} -o cyclonedx-json > container-image.att.json
+        cosign attach attestation ${{ inputs.containerReference }} --attestation container-image.att.json
+        # TODO: type should be auto-discovered after issue is resolved:
+        # https://github.com/sigstore/cosign/issues/2264
+        cosign verify-attestation ${{ inputs.containerReference }} --type 'https://cyclonedx.org/bom' --key env://COSIGN_PUBLIC_KEY
+        grype ${{ inputs.containerReference }} --fail-on high --only-fixed
+      shell: bash
+      env:
+        # COSIGN_EXPERIMENTAL: 1 # This breaks verification with HTTP 404
+        COSIGN_PUBLIC_KEY: ${{ inputs.cosignPublicKey }}
+        COSIGN_PRIVATE_KEY: ${{ inputs.cosignPrivateKey }}
+        COSIGN_PASSWORD: ${{ inputs.cosignPassword }}

.github/workflows/build-access-manager-image.yml

@@ -37,3 +37,6 @@ jobs:
           projectVersion: "0.0.0"
           dockerfile: access_manager/Dockerfile
           githubToken: ${{ secrets.GITHUB_TOKEN }}
+          cosignPublicKey: ${{ startsWith(github.ref, 'refs/heads/release/v') && secrets.COSIGN_PUBLIC_KEY || secrets.COSIGN_DEV_PUBLIC_KEY }}
+          cosignPrivateKey: ${{ startsWith(github.ref, 'refs/heads/release/v') && secrets.COSIGN_PRIVATE_KEY || secrets.COSIGN_DEV_PRIVATE_KEY }}
+          cosignPassword: ${{ startsWith(github.ref, 'refs/heads/release/v') && secrets.COSIGN_PASSWORD || secrets.COSIGN_DEV_PASSWORD }}

.github/workflows/build-constellation-node-operator.yml

@@ -31,3 +31,6 @@ jobs:
           name: node-operator
           sourceDir: operators/constellation-node-operator
           githubToken: ${{ secrets.GITHUB_TOKEN }}
+          cosignPublicKey: ${{ startsWith(github.ref, 'refs/heads/release/v') && secrets.COSIGN_PUBLIC_KEY || secrets.COSIGN_DEV_PUBLIC_KEY }}
+          cosignPrivateKey: ${{ startsWith(github.ref, 'refs/heads/release/v') && secrets.COSIGN_PRIVATE_KEY || secrets.COSIGN_DEV_PRIVATE_KEY }}
+          cosignPassword: ${{ startsWith(github.ref, 'refs/heads/release/v') && secrets.COSIGN_PASSWORD || secrets.COSIGN_DEV_PASSWORD }}

.github/workflows/build-joinservice-image.yml

@@ -39,3 +39,6 @@ jobs:
           projectVersion: "0.0.0"
           dockerfile: joinservice/Dockerfile
           githubToken: ${{ secrets.GITHUB_TOKEN }}
+          cosignPublicKey: ${{ startsWith(github.ref, 'refs/heads/release/v') && secrets.COSIGN_PUBLIC_KEY || secrets.COSIGN_DEV_PUBLIC_KEY }}
+          cosignPrivateKey: ${{ startsWith(github.ref, 'refs/heads/release/v') && secrets.COSIGN_PRIVATE_KEY || secrets.COSIGN_DEV_PRIVATE_KEY }}
+          cosignPassword: ${{ startsWith(github.ref, 'refs/heads/release/v') && secrets.COSIGN_PASSWORD || secrets.COSIGN_DEV_PASSWORD }}

.github/workflows/build-kms-image.yml

@@ -38,3 +38,6 @@ jobs:
           projectVersion: "0.0.0"
           dockerfile: kms/Dockerfile
           githubToken: ${{ secrets.GITHUB_TOKEN }}
+          cosignPublicKey: ${{ startsWith(github.ref, 'refs/heads/release/v') && secrets.COSIGN_PUBLIC_KEY || secrets.COSIGN_DEV_PUBLIC_KEY }}
+          cosignPrivateKey: ${{ startsWith(github.ref, 'refs/heads/release/v') && secrets.COSIGN_PRIVATE_KEY || secrets.COSIGN_DEV_PRIVATE_KEY }}
+          cosignPassword: ${{ startsWith(github.ref, 'refs/heads/release/v') && secrets.COSIGN_PASSWORD || secrets.COSIGN_DEV_PASSWORD }}

.github/workflows/build-micro-service-manual.yml

@@ -62,3 +62,6 @@ jobs:
           dockerfile: ${{ env.microServiceDockerfile }}
           pushTag: ${{ inputs.imageTag }}
           githubToken: ${{ secrets.GITHUB_TOKEN }}
+          cosignPublicKey: ${{ startsWith(github.ref, 'refs/heads/release/v') && secrets.COSIGN_PUBLIC_KEY || secrets.COSIGN_DEV_PUBLIC_KEY }}
+          cosignPrivateKey: ${{ startsWith(github.ref, 'refs/heads/release/v') && secrets.COSIGN_PRIVATE_KEY || secrets.COSIGN_DEV_PRIVATE_KEY }}
+          cosignPassword: ${{ startsWith(github.ref, 'refs/heads/release/v') && secrets.COSIGN_PASSWORD || secrets.COSIGN_DEV_PASSWORD }}

.github/workflows/build-operator-manual.yml

@@ -5,6 +5,7 @@ on:
     inputs:
       imageTag:
         description: "Container image tag."
+        required: false
 
 jobs:
   build-operator-manual:
@@ -29,3 +30,6 @@ jobs:
           sourceDir: operators/constellation-node-operator
           githubToken: ${{ secrets.GITHUB_TOKEN }}
           pushTag: ${{ inputs.imageTag }}
+          cosignPublicKey: ${{ startsWith(github.ref, 'refs/heads/release/v') && secrets.COSIGN_PUBLIC_KEY || secrets.COSIGN_DEV_PUBLIC_KEY }}
+          cosignPrivateKey: ${{ startsWith(github.ref, 'refs/heads/release/v') && secrets.COSIGN_PRIVATE_KEY || secrets.COSIGN_DEV_PRIVATE_KEY }}
+          cosignPassword: ${{ startsWith(github.ref, 'refs/heads/release/v') && secrets.COSIGN_PASSWORD || secrets.COSIGN_DEV_PASSWORD }}

.github/workflows/build-verification-service.yml

@@ -35,3 +35,6 @@ jobs:
           projectVersion: "0.0.0"
           dockerfile: verify/Dockerfile
           githubToken: ${{ secrets.GITHUB_TOKEN }}
+          cosignPublicKey: ${{ startsWith(github.ref, 'refs/heads/release/v') && secrets.COSIGN_PUBLIC_KEY || secrets.COSIGN_DEV_PUBLIC_KEY }}
+          cosignPrivateKey: ${{ startsWith(github.ref, 'refs/heads/release/v') && secrets.COSIGN_PRIVATE_KEY || secrets.COSIGN_DEV_PRIVATE_KEY }}
+          cosignPassword: ${{ startsWith(github.ref, 'refs/heads/release/v') && secrets.COSIGN_PASSWORD || secrets.COSIGN_DEV_PASSWORD }}

.github/workflows/release-cli.yml

@@ -71,20 +71,29 @@ jobs:
           AZURE_SUBSCRIPTION_ID=0d202bbb-4fa7-4af8-8125-58c269a05435 go run . > versions-manifest.json
           cat versions-manifest.json
 
-      - name: Build SBOMs
+      - name: Download syft & grype
         run: |
-          SYFT_VERSION=0.55.0
+          SYFT_VERSION=0.59.0
+          GRYPE_VERSION=0.50.2
           curl -LO https://github.com/anchore/syft/releases/download/v${SYFT_VERSION}/syft_${SYFT_VERSION}_linux_amd64.tar.gz
           tar -xzf syft_${SYFT_VERSION}_linux_amd64.tar.gz
           ./syft version
-          ./syft . --catalogers go-module --file constellation.spdx.sbom -o spdx-json
+          curl -LO https://github.com/anchore/grype/releases/download/v${GRYPE_VERSION}/grype_${GRYPE_VERSION}_linux_amd64.tar.gz
-          CONTAINER_VERSION=${GITHUB_REF##*/}
+          tar -xzf grype_${GRYPE_VERSION}_linux_amd64.tar.gz
-          ./syft ghcr.io/edgelesssys/constellation/verification-service:${CONTAINER_VERSION} --file verification-service.spdx.sbom -o spdx-json
+          ./grype version
-          ./syft ghcr.io/edgelesssys/constellation/access-manager:${CONTAINER_VERSION} --file access-manager.spdx.sbom -o spdx-json
+          echo $(pwd) >> $GITHUB_PATH
-          ./syft ghcr.io/edgelesssys/constellation/join-service:${CONTAINER_VERSION} --file join-service.spdx.sbom -o spdx-json
+        shell: bash
-          ./syft ghcr.io/edgelesssys/constellation/kmsserver:${CONTAINER_VERSION} --file kmsserver.spdx.sbom -o spdx-json
+
-          ./syft ghcr.io/edgelesssys/constellation/node-operator:${CONTAINER_VERSION} --file node-operator.spdx.sbom -o spdx-json
+      - name: Build signed SBOMs
-        if: startsWith(github.ref, 'refs/tags/v')
+        run: |
+          syft . --catalogers go-module --file constellation.spdx.sbom -o spdx-json
+          cosign sign-blob --key env://COSIGN_PRIVATE_KEY constellation.spdx.sbom > constellation.spdx.sbom.sig
+          grype constellation.spdx.sbom --fail-on high --only-fixed
+        env:
+          COSIGN_EXPERIMENTAL: 1
+          cosignPublicKey: ${{ startsWith(github.ref, 'refs/tags/v') && secrets.COSIGN_PUBLIC_KEY || secrets.COSIGN_DEV_PUBLIC_KEY }}
+          cosignPrivateKey: ${{ startsWith(github.ref, 'refs/tags/v') && secrets.COSIGN_PRIVATE_KEY || secrets.COSIGN_DEV_PRIVATE_KEY }}
+          cosignPassword: ${{ startsWith(github.ref, 'refs/tags/v') && secrets.COSIGN_PASSWORD || secrets.COSIGN_DEV_PASSWORD }}
 
       - name: Create release with artifacts
         # GitHub endorsed release project. See: https://github.com/actions/create-release
@@ -96,4 +105,5 @@ jobs:
             build/constellation-*
             build/cosign.pub
             hack/build-manifest/versions-manifest.json
-            *.spdx.sbom
+            constellation.spdx.sbom
+            constellation.spdx.sbom.sig

CHANGELOG.md

@@ -21,6 +21,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ## [Unreleased]
 
 ### Added
+- Sign generated SBOMs and store container image SBOMs in registry for easier usage.
 
 ### Changed
 <!-- For changes in existing functionality.  -->

docs/docs/workflows/sbom.md

@@ -0,0 +1,87 @@
+# Consume software bill of materials (SBOMs)
+
+Constellation builds produce a [software bill of materials (SBOM)](https://www.ntia.gov/SBOM) for each generated [artifact](../architecture/components.md).
+You can use SBOMs to make informed decisions about dependencies and vulnerabilities in a given application. Enterprises rely on SBOMs to maintain an inventory of used applications, which allows them to take data-driven approaches to managing risks related to vulnerabilities.
+
+SBOMs for Constellation are generated using [Syft](https://github.com/anchore/syft), signed using [Cosign](https://github.com/sigstore/cosign), and stored with the produced artifact.
+
+:::note
+The public key for Edgeless Systems' long-term code-signing key is:
+```
+-----BEGIN PUBLIC KEY-----
+MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAEf8F1hpmwE+YCFXzjGtaQcrL6XZVT
+JmEe5iSLvG1SyQSAew7WdMKF6o9t8e2TFuCkzlOhhlws2OHWbiFZnFWCFw==
+-----END PUBLIC KEY-----
+```
+The public key is also available for download at https://edgeless.systems/es.pub and in the Twitter profile [@EdgelessSystems](https://twitter.com/EdgelessSystems).
+
+Make sure the key is available in a file named `cosign.pub` to execute the following examples.
+:::
+
+## Verify and download SBOMs
+
+The following sections detail how to work with each type of artifact to verify and extract the SBOM.
+
+### Constellation CLI
+
+The SBOM for Constellation CLI is made available on the [GitHub release page](https://github.com/edgelesssys/constellation/releases). The SBOM (`constellation.spdx.sbom`) and corresponding signature (`constellation.spdx.sbom.sig`) are valid for each Constellation CLI for a given version, regardless of architecture and operating system.
+
+```bash
+curl -LO https://github.com/edgelesssys/constellation/releases/download/v2.2.0/constellation.spdx.sbom
+curl -LO https://github.com/edgelesssys/constellation/releases/download/v2.2.0/constellation.spdx.sbom.sig
+cosign verify-blob --key cosign.pub --signature constellation.spdx.sbom.sig constellation.spdx.sbom
+```
+
+### Container Images
+
+SBOMs for container images are [attached to the image using Cosign](https://docs.sigstore.dev/cosign/other_types#sboms-software-bill-of-materials) and uploaded to the same registry.
+
+As a consumer, use cosign to download and verify the SBOM:
+
+```bash
+# Verify and download the attestation statement
+cosign verify-attestation ghcr.io/edgelesssys/constellation/verification-service@v2.2.0 --type 'https://cyclonedx.org/bom' --key cosign.pub --output-file verification-service.att.json
+# Extract SBOM from attestation statement
+jq -r .payload verification-service.att.json | base64 -d > verification-service.cyclonedx.sbom
+```
+
+A successful verification should result in similar output:
+
+```shell-session
+$ cosign verify-attestation ghcr.io/edgelesssys/constellation/verification-service@v2.2.0 --type 'https://cyclonedx.org/bom' --key cosign.pub --output-file verification-service.sbom
+
+Verification for ghcr.io/edgelesssys/constellation/verification-service@v2.2.0 --
+The following checks were performed on each of these signatures:
+  - The cosign claims were validated
+  - The signatures were verified against the specified public key
+$ jq -r .payload verification-service.sbom | base64 -d > verification-service.cyclonedx.sbom
+```
+
+:::note
+
+This example considers only the `verification-service`. The same approach works for all containers in the [Constellation container registry](https://github.com/orgs/edgelesssys/packages?repo_name=constellation).
+
+:::
+
+<!--
+TODO: Once mkosi is implemented
+## Operating System
+-->
+
+## Vulnerability scanning
+
+You can use a plethora of tools to consume SBOMs. This section provides suggestions for tools that are popular and known to produce reliable results, but any tool that consumes [SPDX](https://spdx.dev/) or [CycloneDX](https://cyclonedx.org/) files should work.
+
+Syft is able to [convert between the two formats](https://github.com/anchore/syft#format-conversion-experimental) in case you require a specific type.
+
+### Grype
+
+[Grype](https://github.com/anchore/grype) is a CLI tool that lends itself well for integration into CI/CD systems or local developer machines. It's also able to consume the signed attestation statement directly and does the verification in one go.
+
+```bash
+grype att:verification-service.sbom --key cosign.pub --add-cpes-if-none -q
+```
+
+### Dependency Track
+
+[Dependency Track](https://dependencytrack.org/) is one of the oldest and most mature solutions when it comes to managing software inventory and vulnerabilities. Once imported, it continuously scans SBOMs for new vulnerabilities. It supports the CycloneDX format and provides direct guidance on how to comply with [U.S. Executive Order 14028](https://docs.dependencytrack.org/usage/executive-order-14028/).

docs/sidebars.js

@@ -168,6 +168,11 @@ const sidebars = {
           label: 'Use Azure trusted launch VMs',
           id: 'workflows/trusted-launch',
         },
+        {
+          type: 'doc',
+          label: 'Consume SBOMs',
+          id: 'workflows/sbom',
+        },
         {
           type: 'doc',
           label: 'Troubleshooting',

docs/styles/Vocab/constellation/accept.txt

@@ -18,6 +18,7 @@ Filestore
 Fulcio
 Mbps
 Gbps
+Grype
 iam
 IAM
 initramfs
@@ -36,6 +37,7 @@ Rekor
 resizable
 rollout
 sigstore
+Syft
 systemd
 [Uu]nencrypted
 unspoofable