feat(security-actions/scan-docker-image): support trivy_db_cache as alternate

.github/workflows/docker-image-scan.yml

@@ -63,7 +63,9 @@ jobs:
       with:
         asset_prefix: kong-gateway-dev-linux-amd64
         image: ${{env.IMAGE}}@${{ steps.image_manifest_metadata.outputs.amd64_sha }}
-        skip_cis_scan: true
+        skip_cis_scan: false
+        trivy_db_cache: Kong/trivy-db-mirror@master
+        trivy_db_cache_token: ${{ secrets.PAT }}
 
     - name: Scan ARM64 Image digest
       if: steps.image_manifest_metadata.outputs.manifest_list_exists == 'true' && steps.image_manifest_metadata.outputs.arm64_sha != ''
@@ -73,7 +75,7 @@ jobs:
         asset_prefix: test.kong-gateway-dev-linux-arm64
         image: ${{env.IMAGE}}@${{ steps.image_manifest_metadata.outputs.arm64_sha }}
         upload-sbom-release-assets: true
-        skip_cis_scan: true
+        skip_cis_scan: false
 
   test-download-sbom:
     if: ${{ github.event_name != 'pull_request' || github.event.pull_request.head.repo.full_name == github.repository }}

security-actions/scan-docker-image/README.md

@@ -5,8 +5,8 @@
 - [Scan Docker Image](./action.yml) is a action for container SCA image scanning and CIS benchmarks. The action produces an SBOM, CVE, and CIS benchmark scanning and reports for a given image.
   - Tools used:
     - [syft](https://github.com/anchore/syft) generates a Software Bill of Materials (SBOM)
-    - [grype](https://github.com/anchore/grype) vulnerability scanner for container images
-    - [trivy](https://github.com/aquasecurity/trivy) compliance scanner for docker-cis 
+    - [grype](https://github.com/anchore/grype) vulnerability scanner for CVEs in container images
+    - [trivy](https://github.com/aquasecurity/trivy)  compliance scanner for docker-cis benchmarks
 
 ### Scan Docker Image
 
@@ -16,7 +16,7 @@
 
 - Leverages the syft action to generate an SBOM based on input parameters and uploads it as a github workflow artifact
 
-#### Vulnerability Scanning Working
+#### Grype Vulnerability Scanning Working
 
 - Action performs a scan of the sbom based on a user provided grype configuration:
   - First iteration:
@@ -32,6 +32,14 @@
     - Additional grype ignore rules and matches are applied and suppressed in console log
     - Helps developers better prioritize cve's by suppressing false positives and bypass cve's during hot fixes using break glass strategy
 
+#### Trivy Compliance Scanner Working
+- By default, trivy scans the docker image against `docker-cis-1.6.0` benchmarks
+- Trivy compliance scanner leverages `trivy-db` for CIS benchmarks
+  - By default, it downloads the latest DB from upstream `mirror.gcr.io/aquasec/trivy-db`  pull through cache mirror
+  - __[_OPTIONAL_]__  For more availability of `trivy-db` (**i.e bypass rate limiting issues**), refer [how to access cached trivy db for running CIS benchmarks](https://github.com/Kong/trivy-db-mirror?tab=readme-ov-file#how-to-consume-cached-trivy-db-when-invoking-public-shared-actions)
+- Trivy complaince scanner  **DOESNOT** scan for any vulnerabilities in the container image. This process is handled by [grype](https://github.com/anchore/grype)
+
+
 #### Input specification
 
 - Global parameters can be used for enforcement by centralized team across all repositories.
@@ -70,10 +78,13 @@ permissions:
 
 #### User provided input parameters
 
-- Inputs **image** is mandatory
+- Input `image` is **MANDATORY**
 
 - OCI tar balls / Docker archives (OCI compatible) are considered as input type  **Image**
 
+- Input `trivy_db_cache` and `trivy_db_cache_token` are **OPTIONAL**
+  - Refer [how access cached trivy db for CIS benchmarks](https://github.com/Kong/trivy-db-mirror?tab=readme-ov-file#how-to-consume-cached-trivy-db-when-invoking-public-shared-actions)
+
 ```yaml
   asset_prefix:
     description: 'prefix for generated scan artifacts'
@@ -116,6 +127,12 @@ permissions:
     options:
     - 'true'
     - 'false'
+  trivy_db_cache:
+    description: 'GitHub repository containing Trivy DB cache (format: owner/repo@ref). Database should be named `db.tar.gz` on the default branch.'
+    required: false
+  trivy_db_cache_token:
+    description: 'Token for accessing `trivy_db_cache`.'
+    required: false
 ```
 
 #### Output specification
@@ -238,6 +255,7 @@ jobs:
       if: steps.image_manifest_metadata.outputs.amd64_sha != ''
       uses: Kong/public-shared-actions/security-actions/scan-docker-image@main
       with:
+        # Leverages trivy DB config from upstream mirror by default
         asset_prefix: kong-gateway-dev-linux-amd64
         image: ${{env.IMAGE}}@${{ steps.image_manifest_metadata.outputs.amd64_sha }}
 
@@ -248,4 +266,6 @@ jobs:
       with:
         asset_prefix: kong-gateway-dev-linux-arm64
         image: ${{env.IMAGE}}@${{ steps.image_manifest_metadata.outputs.arm64_sha }}
+        trivy_db_cache: <owner/repo@ref>
+        trivy_db_cache_token: ${{ secrets.PAT }} 
 ```

security-actions/scan-docker-image/action.yml

@@ -67,6 +67,12 @@ inputs:
     options:
       - 'true'
       - 'false'
+  trivy_db_cache:
+    description: 'GitHub repository containing Trivy DB cache (format: owner/repo@ref). Database should be named `db.tar.gz` on the default branch.'
+    required: false
+  trivy_db_cache_token:
+    description: 'Token for accessing `trivy_db_cache`.'
+    required: false
 
 outputs:
   cis-json-report:
@@ -302,13 +308,60 @@ runs:
       with:
         files: "${{ steps.meta.outputs.scan_image }}"
 
+    - name: Parse Trivy DB cache input
+      if: inputs.trivy_db_cache != ''
+      shell: bash
+      id: parse_cache
+      run: |
+        REPO=$(echo "${{ inputs.trivy_db_cache }}" | cut -d'@' -f1)
+        REF=$(echo "${{ inputs.trivy_db_cache }}" | cut -d'@' -f2)
+        echo "repository=${REPO}" >> $GITHUB_OUTPUT
+        echo "ref=${REF}" >> $GITHUB_OUTPUT
+
+      # Issue: https://github.com/aquasecurity/trivy/issues/7938
+      # Discussion: https://github.com/aquasecurity/trivy/discussions/7668
+      # Fix: Refer https://github.com/aquasecurity/trivy/discussions/7951 usign mirror.gcr.io 
+    - name: Install Trivy
+      shell: bash
+      run: |
+        curl -sfL https://raw.githubusercontent.com/aquasecurity/trivy/main/contrib/install.sh | sh -s -- -b /usr/local/bin v0.57.1
+
+    - name: Checkout Trivy DB cache
+      if: inputs.trivy_db_cache != ''
+      uses: actions/checkout@v4
+      with:
+        repository: ${{ steps.parse_cache.outputs.repository }}
+        ref: ${{ steps.parse_cache.outputs.ref }}
+        path: trivy-db-cache
+        token: ${{ inputs.trivy_db_cache_token }}
+
+    - name: Setup Trivy DB from cache
+      if: inputs.trivy_db_cache != ''
+      shell: bash
+      run: |
+        # Create Trivy cache directory
+        mkdir -p ~/.cache/trivy/db
+
+        # Extract the DB
+        cd trivy-db-cache
+        tar -xvf db.tar.gz -C ~/.cache/trivy/db
+        cd ..
+        rm -rf trivy-db-cache
+
+    # Issue: https://github.com/aquasecurity/trivy/issues/7938
+    # Fix: Refer https://github.com/aquasecurity/trivy/discussions/7951 usign mirror.gcr.io 
     - name: Generate docker-cis JSON report
-      uses: docker://aquasec/trivy:0.55.2
       if: ${{ inputs.skip_cis_scan != 'true' && steps.meta.outputs.scan_image != '' }}
       id: cis_json
-      with:
-        entrypoint: trivy
-        args: "image ${{ env.input }} ${{ steps.meta.outputs.scan_image }} --compliance ${{ env.compliance }} -f json --ignore-unfixed -o ${{ steps.meta.outputs.cis_json_file }}"
+      shell: bash
+      run: |
+        trivy image ${{ env.input }} \
+          ${{ steps.meta.outputs.scan_image }} \
+          --compliance ${{ env.compliance }} \
+          -f json \
+          --ignore-unfixed \
+          -o ${{ steps.meta.outputs.cis_json_file }} \
+          ${{ inputs.trivy_db_cache != '' && '--cache-dir ~/.cache/trivy --skip-db-update' || '' }}
       env:
         compliance: docker-cis-1.6.0
         input: ${{ steps.docker_tar.outputs.files_exists == 'true' && '--input' || '' }}
@@ -324,10 +377,15 @@ runs:
 
     - name: Inspect docker-cis report
       if: ${{ inputs.skip_cis_scan != 'true' && steps.meta.outputs.scan_image != '' }}
-      uses: docker://aquasec/trivy:0.55.2
-      with:
-        entrypoint: trivy
-        args: "image ${{ env.input }} ${{ steps.meta.outputs.scan_image }} --compliance ${{ env.compliance }} -f table --ignore-unfixed --exit-code ${{ env.exit-code }}"
+      shell: bash
+      run: |
+        trivy image ${{ env.input }} \
+          ${{ steps.meta.outputs.scan_image }} \
+          --compliance ${{ env.compliance }} \
+          -f table \
+          --ignore-unfixed \
+          --exit-code ${{ env.exit-code }} \
+          ${{ inputs.trivy_db_cache != '' && '--cache-dir ~/.cache/trivy --skip-db-update' || '' }}
       env:
         exit-code: ${{ (steps.meta.outputs.global_enforce_build_failure == 'true' || inputs.fail_build == 'true') && '1' || '0' }}
         compliance: docker-cis-1.6.0