Out of the Box Supply Chain with Testing and Scanning for Supply Chain Choreographer

This topic provides an overview of Out of the Box Supply Chain with Testing and Scanning for Supply Chain Choreographer.

This package contains Cartographer Supply Chains that tie together a series of Kubernetes resources that drive a developer-provided workload from source code to a Kubernetes configuration ready to be deployed to a cluster. It contains supply chains that pass the source code through testing and vulnerability scanning, and also the container image.

This package includes all the capabilities of the Out of the Box Supply Chain With Testing, but adds source and image scanning using Grype.

Workloads that use source code or prebuilt images perform the following:

Building from source code:
1. Watching a Git Repository or local directory for changes
2. Running tests from a developer-provided Tekton pipeline
3. Scanning the source code for known vulnerabilities using Grype
4. Building a container image out of the source code with Buildpacks
5. Scanning the image for known vulnerabilities
6. Applying operator-defined conventions to the container definition
7. Deploying the application to the same cluster
8. Alternatively, outputting a Carvel Package containing the application to a Git repository. See Carvel Package Supply Chains.
Using a prebuilt application image:
1. Scanning the image for known vulnerabilities
2. Applying operator-defined conventions to the container definition
3. Creating a deliverable object for deploying the application to a cluster
4. Alternatively, outputting a Carvel package containing the application to a Git repository. See Carvel Package Supply Chains.

Prerequisites

To use this supply chain, verify that:

Out of the Box Templates is installed.
Out of the Box Supply Chain With Testing is NOT installed.
Out of the Box Supply Chain With Testing and Scanning is installed.
The developer namespace is configured with the objects according to Out of the Box Supply Chain With Testing guidance. This supply chain exists in addition to the Supply Chain with testing.
(Optional) Out of the Box Delivery Basic is installed if you want to deploy the application to the same cluster as the workload and supply chains.

Verify that you have the supply chains with scanning, not with testing, installed by running:

tanzu apps cluster-supply-chain list

NAME                      LABEL SELECTOR
source-test-scan-to-url   apps.tanzu.vmware.com/has-tests=true,apps.tanzu.vmware.com/workload-type=web
source-to-url             apps.tanzu.vmware.com/workload-type=web

If you see source-test-to-url in the list, the setup is wrong. You must not have the source-test-to-url installed at the same time as source-test-scan-to-url.

Developer namespace

This example builds on the previous Out of the Box Supply Chain examples, so only additions are included here.

To ensure that you configured the namespace correctly, it is important that the namespace has the objects that you configured in the other supply chain setups:

registries secrets: Kubernetes secrets of type kubernetes.io/dockerconfigjson that contain credentials for pushing and pulling the container images built by the supply chain and the installation of Tanzu Application Platform.
service account: The identity to be used for any interaction with the Kubernetes API made by the supply chain.
rolebinding: Grant to the identity the necessary roles for creating the resources prescribed by the supply chain.

For more information about the preceding objects, see Out of the Box Supply Chain Basic.
Tekton pipeline: A pipeline runs whenever the supply chain hits the stage of testing the source code.

For more information, see Out of the Box Supply Chain Testing.

And the new objects, that you create here:

scan policy: Defines what to do with the results taken from scanning the source code and image produced. For more information, see ScanPolicy section.
source scan template: A template of how TaskRuns are created for scanning the source code. See ScanTemplate section.
image scan template: A template of how TaskRuns are created for scanning the image produced by the supply chain. See ScanTemplate section.

The following section includes details about the new objects, compared to Out of the Box Supply Chain With Testing.

Updates to the developer namespace

For source and image scans, scan templates and scan policies must exist in the same namespace as the workload. These define:

ScanTemplate: how to run a scan, allowing one to change details about the execution of the scan (either for images or source code)
ScanPolicy: how to evaluate whether the artifacts scanned are compliant. For example, allowing one to be either very strict, or restrictive about particular vulnerabilities found.

The names of the objects must match the names in the example with default installation configurations. This is overridden either by using the ootb_supply_chain_testing_scanning package configuration in the tap-values.yaml file or by using workload parameters:

To override by using the ootb_supply_chain_testing_scanning package configuration, make the following modification to your tap-values.yaml file and perform a Tanzu Application Platform update.
```
ootb_supply_chain_testing_scanning:
  scanning:
    source:
      policy: SCAN-POLICY
      template: SCAN-TEMPLATE
    image:
      policy: SCAN-POLICY
      template: SCAN-TEMPLATE
```
Where SCAN-POLICY and SCAN-TEMPLATE are the names of the ScanPolicy and ScanTemplate.
To override through workload parameters, use the these commands.
```
tanzu apps workload apply WORKLOAD --param "scanning_source_policy=SCAN-POLICY" -n DEV-NAMESPACE
tanzu apps workload apply WORKLOAD --param "scanning_source_template=SCAN-TEMPLATE" -n DEV-NAMESPACE
```
Where:
- WORKLOAD is the name of the workload.
- SCAN-POLICY and SCAN-TEMPLATE are the names of the ScanPolicy and ScanTemplate.
- DEV-NAMESPACE is the developer namespace.
For more information, see Create or update a workload.

ScanPolicy

The ScanPolicy defines a set of rules to evaluate for a particular scan to consider the artifacts (image or source code) either compliant or not.

When a ImageScan or SourceScan is created to run a scan, those reference a policy whose name must match the following sample scan-policy:

---
apiVersion: scanning.apps.tanzu.vmware.com/v1beta1
kind: ScanPolicy
metadata:
  name: scan-policy
  labels:
    'app.kubernetes.io/part-of': 'enable-in-gui'
spec:
  regoFile: |
    package main

    # Accepted Values: "Critical", "High", "Medium", "Low", "Negligible", "UnknownSeverity"
    notAllowedSeverities := ["Critical", "High", "UnknownSeverity"]
    ignoreCves := []

    contains(array, elem) = true {
      array[_] = elem
    } else = false { true }

    isSafe(match) {
      severities := { e | e := match.ratings.rating.severity } | { e | e := match.ratings.rating[_].severity }
      some i
      fails := contains(notAllowedSeverities, severities[i])
      not fails
    }

    isSafe(match) {
      ignore := contains(ignoreCves, match.id)
      ignore
    }

    deny[msg] {
      comps := { e | e := input.bom.components.component } | { e | e := input.bom.components.component[_] }
      some i
      comp := comps[i]
      vulns := { e | e := comp.vulnerabilities.vulnerability } | { e | e := comp.vulnerabilities.vulnerability[_] }
      some j
      vuln := vulns[j]
      ratings := { e | e := vuln.ratings.rating.severity } | { e | e := vuln.ratings.rating[_].severity }
      not isSafe(vuln)
      msg = sprintf("CVE %s %s %s", [comp.name, vuln.id, ratings])
    }

See Writing Policy Templates.

ScanTemplate

A ScanTemplate defines the PodTemplateSpec used by a TaskRun to run a particular scan (image or source). When the supply chain initiates an ImageScan or SourceScan, they reference these templates which must live in the same namespace as the workload with the names matching the following:

source scanning (blob-source-scan-template)
image scanning (private-image-scan-template)

You can install the Grype ScanTemplates in the namespace that you are writing the workload to with Namespace Provisioner. See Provision developer namespaces in Namespace Provisioner.

Label the namespace that you are writing the workload to, with the default namespace_selector apps.tanzu.vmware.com/tap-ns="", by running:

kubectl label namespaces YOUR-DEV-NAMESPACE apps.tanzu.vmware.com/tap-ns=""

Note
Although you can customize the templates, if you are following the Getting Started guide, VMware recommends that you follow what is provided in the installation of grype.scanning.apps.tanzu.vmware.com. For more information, see About Source and Image Scans.

Enable storing scan results

To enable SCST - Scan to store scan results by using SCST - Store, see Developer namespace setup for exporting the SCST - Store CA certificate and authentication token to the developer namespace.

Allow multiple Tekton pipelines in a namespace

You can configure your developer namespace to include more than one pipeline using either of the following methods:

Use a single pipeline running on a container image that includes testing tools and runs a common script to execute tests. This allows you to accommodate multiple workloads based in different languages in the same namespace that use a common make test script, as shown in the following example:

apiVersion: tekton.dev/v1beta1
kind: Pipeline
metadata:
  name: developer-defined-tekton-pipeline
  labels:
    apps.tanzu.vmware.com/pipeline: test
spec:
  #...
        steps:
          - name: test
            image: <image_that_has_JDK_and_Go>
            script: |-
              cd `mktemp -d`
              wget -qO- $(params.source-url) | tar xvz -m
              make test

Update the pipeline resources to include labels that differentiate between the pipelines. For example, differentiate between Java and Go pipelines by adding labels for Java and Go:

apiVersion: tekton.dev/v1beta1
kind: Pipeline
metadata:
  name: java-tests
  labels:
    apps.tanzu.vmware.com/pipeline: test
    apps.tanzu.vmware.com/language: java
spec:
  #...
        steps:
          - name: test
            image: gradle
            script: |-
              # ...
              ./mvnw test
---
apiVersion: tekton.dev/v1beta1
kind: Pipeline
metadata:
  name: go-tests
  labels:
    apps.tanzu.vmware.com/pipeline: test
    apps.tanzu.vmware.com/language: go
spec:
  #...
        steps:
          - name: test
            image: golang
            script: |-
              # ...
              go test -v ./...

To match the correct pipeline, you add a testing_pipeline_matching_labels parameter to the workload. For example, if you want to match to the Java pipeline, you have the following workload.yaml:

apiVersion: carto.run/v1alpha1
kind: Workload
metadata:
  name: sample-java-app
  labels:
    apps.tanzu.vmware.com/has-tests: true
    apps.tanzu.vmware.com/workload-type: web
    app.kubernetes.io/part-of: sample-java-app
spec:
  params:
    - name: testing_pipeline_matching_labels
      value:
        apps.tanzu.vmware.com/pipeline: test
        apps.tanzu.vmware.com/language: java
  ...

This matches the workload to the pipeline with the apps.tanzu.vmware.com/language: java label.

Developer workload

With the ScanPolicy and ScanTemplate objects, with the required names set, submitted to the same namespace where the workload is submitted, you are ready to submit your workload.

Regardless of the workflow being targeted, such as local development or GitOps, the workload configuration details are the same as in Out of the Box Supply Chain Basic, except that you mark the workload as having tests enabled.

For example:

tanzu apps workload create tanzu-java-web-app \
  --git-branch main \
  --git-repo https://github.com/vmware-tanzu/application-accelerator-samples \
  --sub-path tanzu-java-web-app \
  --label apps.tanzu.vmware.com/has-tests=true \
  --label app.kubernetes.io/part-of=tanzu-java-web-app \
  --type web

Create workload:
      1 + |---
      2 + |apiVersion: carto.run/v1alpha1
      3 + |kind: Workload
      4 + |metadata:
      5 + |  labels:
      6 + |    apps.tanzu.vmware.com/workload-type: web
      7 + |    apps.tanzu.vmware.com/has-tests: "true"
      8 + |    app.kubernetes.io/part-of: tanzu-java-web-app
      9 + |  name: tanzu-java-web-app
     10 + |  namespace: default
     11 + |spec:
     12 + |  source:
     13 + |    git:
     14 + |      ref:
     15 + |        branch: main
     16 + |      url: https://github.com/vmware-tanzu/application-accelerator-samples
     17 + |    subPath: tanzu-java-web-app

CVE triage workflow

The Supply Chain halts progression if either a SourceScan (sourcescans.scanning.apps.tanzu.vmware.com) or an ImageScan (imagescans.scanning.apps.tanzu.vmware.com) fails policy enforcement through the ScanPolicy (scanpolicies.scanning.apps.tanzu.vmware.com).

This can prevent source code from building or images deploying that contain vulnerabilities that are in violation of the user-defined scan policy. For information about learning how to handle these vulnerabilities and unblock your Supply Chain, see Triaging and Remediating CVEs.

Scan Images using a different scanner

Supply Chain Security Tools - Scan includes additional integrations for running an image scan using Snyk.