Troubleshoot Supply Chain Security Tools - Scan

This topic describes troubleshooting methods you can use with Supply Chain Security Tools (SCST) - Scan.

Debugging commands

Run these commands to get more logs and details about the errors around scanning. The TaskRuns and pods persist for a predefined amount of seconds before getting deleted. (deleteScanJobsSecondsAfterFinished is the tap pkg variable that defines this)

Debug Tekton TaskRun

To retrieve TaskRun events run:

kubectl describe taskrun TASKRUN-NAME -n DEV-NAMESPACE

Where:

TASKRUN-NAME is the name of the TaskRun.
DEV-NAMESPACE is the name of the developer namespace you want to use.

Debug Scan pods

Run the following to get error logs from a pod when scan pods are in a failing state:

kubectl logs scan-pod-name -n DEV-NAMESPACE

Where DEV-NAMESPACE is the name of the developer namespace you want to use.

For more information, about debugging Kubernetes pods see here

The following is an example of a successful scan run output:

scan:
  cveCount:
    critical: 20
    high: 120
    medium: 114
    low: 9
    unknown: 0
  scanner:
    name: Grype
    vendor: Anchore
    version: v0.37.0
  reports:
  - /workspace/scan.xml
eval:
  violations:
  - CVE node-fetch GHSA-w7rc-rwvf-8q5r Low
store:
  locations:
  - https://metadata-store-app.metadata-store.svc.cluster.local:8443/api/sources?repo=hound&sha=5805c6502976c10f5529e7f7aeb0af0c370c0354&org=houndci

A scan run that has an error means that one of the init containers: scan-plugin, metadata-store-plugin, compliance-plugin, summary, or any other additional containers had a failure.

To inspect for a specific init container in a pod run:

kubectl logs scan-pod-name -n DEV-NAMESPACE -c init-container-name

Where DEV-NAMESPACE is the name of the developer namespace you want to use.

For debug init container tips, see Debug Init Containers in the Kubernetes documentation.

Debug SourceScan and ImageScan

To retrieve status conditions of an SourceScan and an ImageScan, run:

kubectl describe sourcescan SOURCE-SCAN -n DEV-NAMESPACE

Where:

DEV-NAMESPACE is the name of the developer namespace you want to use.
SOURCE-SCAN is the name of the SourceScan you want to use.

kubectl describe imagescan IMAGE-SCAN -n DEV-NAMESPACE

Where:

DEV-NAMESPACE is the name of the developer namespace you want to use.
IMAGE-SCAN is the name of the ImageScan you want to use.

Under Status.Conditions, for a condition look at the Reason, Type, and Message values that use the keyword Error to investigate issues.

Debug Scanning within a SupplyChain

For Tanzu workload commands for tailing build and runtime logs, and getting workload status and details, see Troubleshoot Apps CLI.

View the scan-controller manager logs

To retrieve scan-controller manager logs:

kubectl -n scan-link-system logs -f deployment/scan-link-controller-manager -c manager

Restarting Deployment

If you encounter an issue with the scan-link controller not starting, run the following to restart the deployment to see if it is reproducible or flaking when starting:

kubectl rollout restart deployment scan-link-controller-manager -n scan-link-system

Troubleshoot the scanner to Metadata Store configuration

If you encounter this issue:

✖  Error: Post "https://metadata-store.tap.tanzu.example.com/api/sourceReport?": \
tls: failed to verify certificate: x509: certificate signed by unknown authority

ensure that the caSecret from the scanner DEV-NAMESPACE matches the caSecret from the METADATASTORE-NAMESPACE namespace:

If you provided an ingress connection to the store, delete it. In a single cluster, the connection between the scanning pod and the Metadata Store happens inside the cluster and does not pass through ingress. This is automatically configured. You do not need to provide an ingress connection to the store.
Get the caSecret.name. If you are using a multicluster setup, retrieve grype.metadataStore.caSecret.name from the Grype configuration as in this example:
```
grype:
  metadataStore:
    caSecret:
      name: store-ca-cert
      importFromNamespace: metadata-store-secrets
```
Note
caSecret.name is set to store-ca-cert. For more information, see Set up multicluster Supply Chain Security Tools (SCST) - Scan 1.0.

If you are using a single-cluster setup, the default value for grype.metadataStore.caSecret.name is app-tls-cert. For more information, see Install Supply Chain Security Tools - Scan.
Verify that the CA-SECRET secret exists in the DEV-NAMESPACE by running:
```
kubectl get secret CA-SECRET -n DEV-NAMESPACE
```
If the secret CA-SECRET doesn’t exist in your DEV-NAMESPACE, verify that the CA-SECRET exists in the METADATASTORE-NAMESPACE namespace by running:
```
kubectl get secret CA-SECRET -n METADATASTORE-NAMESPACE
```
Where METADATASTORE-NAMESPACE is the namespace that contains the secret CA-SECRET.

If you are using a single cluster, it is configured by using the metadata-store namespace. If multicluster, it is configured by using metadata-store-secrets.

If CA-SECRET does not exist in the Metadata Store namespace, see Custom certificate configuration to configure the certificate.
Verify that the secretexport and secretimport exist and are reconciling successfully by running:
```
kubectl get secretexports.secretgen.carvel.dev -n `METADATASTORE-NAMESPACE`
kubectl get secretimports.secretgen.carvel.dev -n `DEV-NAMESPACE`
```
SCST - Store creates the single-cluster secretexport by default. For more information, see Deployment details and configuration. For information about creating the multicluster secretexport, see Set up multicluster SCST - Scan 1.0.
Verify that the ca.crt field in both secrets from METADATASTORE-NAMESPACE and DEV-NAMESPACE match, or that the ca.crt field of the secret in the METADATASTORE-NAMESPACE includes the ca.crt field of the DEV-NAMESPACE secret.

To do so, base64-decode both secrets and verify that there is a match by running:
```
kubectl get secret CA-SECRET -n DEV-NAMESPACE -o json | jq -r '.data."ca.crt"' | base64 -d
kubectl get secret CA-SECRET -n METADATASTORE-NAMESPACE -o json | jq -r '.data."ca.crt"' | base64 -d
```
The certificates in the METADATASTORE-NAMESPACE and DEV-NAMESPACE must have a match for the scanner to connect to metadata-store.

Troubleshooting issues

See the following sections for troubleshooting specific known issues.

Source scan missing in supply chain

The source scan step is opt-in in Tanzu Application Platform v1.6 and later to better support languages that resolve dependencies at build time. For more information and how to opt in to source scanning in the out-of-the-box test and scan supply chain, see Scan Types for Supply Chain Security Tools - Scan.

Troubleshoot Grype in air-gapped environments

For information about issues with Grype in air-gapped environments, see Use vulnerability scanning in offline and air-gapped environments.

Missing target SSH secret

Scanning source code from a private source repository requires an SSH secret in the namespace and referenced as grype.targetSourceSshSecret in tap-values.yaml. For more information, see Installing the Tanzu Application Platform Package and Profiles.

If a private source scan is triggered and the secret cannot be found, the scan pod includes a FailedMount warning in Events with the message:

MountVolume.SetUp failed for volume "ssh-secret" : secret "secret-ssh-auth" not found

Where secret-ssh-auth is the value specified in grype.targetSourceSshSecret

Missing target image pull secret

Scanning an image from a private registry requires an image pull secret to exist in the Scan CRs namespace and to be referenced as grype.targetImagePullSecret in tap-values.yaml. For more information, see Installing the Tanzu Application Platform Package and Profiles.

If a private image scan is triggered and the secret is not configured, the scan TaskRun pod’s step-scan-plugin container fails with the following error:

Error: GET https://tanzu.packages.broadcom.com/v2/vse-dev/spring-petclinic/manifests/sha256:128e38c1d3f10401a595c253743bee343967c81e8f22b94e30b2ab8292b3973f: \
UNAUTHORIZED: unauthorized to access repository: vse-dev/spring-petclinic, action: pull: unauthorized to access repository: vse-dev/spring-petclinic, action: pull

Deactivate SCST - Store

SCST - Store is required to install SCST - Scan:

If you install without SCST - Store, edit the configuration to deactivate the Store as follows:
```
---
metadataStore:
  url: ""
```

Install the package with the edited configuration by running:

tanzu package install scan-controller \
 --package scanning.apps.tanzu.vmware.com \
 --version VERSION \
 --namespace tap-install \
 --values-file tap-values.yaml

Resolve incompatible Syft Schema Version

You might encounter the following error:

The provided SBOM has a Syft Schema Version which doesn't match the version that is supported by Grype...

This means that the Syft Schema Version from the provided SBOM does not match the version supported by the installed grype-scanner. There are two different methods to resolve this incompatibility issue:

(Recommended) Install a version of Tanzu Build Service that provides an SBOM with a compatible Syft Schema Version.
Deactivate failOnSchemaErrors in grype-values.yaml as follows:
```
syft:
  failOnSchemaErrors: false
```
For more information, see Install Supply Chain Security Tools - Scan. Although this change bypasses the check on Syft Schema Version, it does not resolve the incompatibility issue and produces a partial scanning result.

Resolve incompatible scan policy

If your scan policy appears to not be enforced, it might be because the Rego file defined in the scan policy is incompatible with the scanner that is being used. For example, the Grype Scanner outputs in the CycloneDX XML format while the Snyk Scanner outputs SPDX JSON.

For an example of a ScanPolicy formatted for SPDX JSON, see Sample ScanPolicy for Snyk in SPDX JSON format

Could not find CA in secret

If you encounter the following issue, it might be because of not exporting app-tls-cert to the correct namespace:

{"level":"error","ts":"2022-06-08T15:20:48.43237873Z","logger":"setup","msg":"Could not find CA in Secret","err":"unable to set up connection to Supply Chain Security Tools - Store"}

Configure ns_for_export_app_cert in your tap-values.yaml file as follows:

metadata_store:
  ns_for_export_app_cert: "DEV-NAMESPACE"

Where DEV-NAMESPACE is the name of the developer namespace you want to use.

If there are multiple developer namespaces, use ns_for_export_app_cert: "*".

Blob Source Scan is reporting the wrong source URL

A Source Scan for a blob artifact can cause reporting the wrong URL for the resource in status.artifact and status.compliantArtifact, passing the remote SSH URL instead of the cluster local fluxcd URL. One symptom of this issue is image-builder failing with a ssh:// is an unsupported protocol error message.

Verify that this is the problem by running: kubectl describe in the affected resource and

kubectl describe sourcescan SOURCE-SCAN-NAME -n DEV-NAMESPACE

Where:

SOURCE-SCAN-NAME is the name of the source scan you want to configure.
DEV-NAMESPACE is the name of the developer namespace you want to use.

Compare spec.blob.url value and status.artifact.blob.url to see if they are different URLs. For example:

...
spec:
  blob:
    ...
    url: http://source-controller.flux-system.svc.cluster.local./gitrepository/sample/repo/8d4cea98b0fa9e0112d58414099d0229f190f7f1.tar.gz
    ...
status:
  artifact:
    blob:
      ...
      url: ssh://[email protected]:sample/repo.git
  compliantArtifact:
    blob:
      ...
      url: ssh://[email protected]:sample/repo.git

This problem happens in SCST - Scan v1.2.0 when you use a Grype Scanner ScanTemplates resource earlier than v1.2.0 because this is a deprecated path. To fix this problem, upgrade your Grype Scanner deployment to v1.2.0 or later. For instructions, see Upgrade to Version v1.2.0

Resolving failing scans that block a Supply Chain

If the Supply Chain is not progressing because of CVEs found in either the SourceScan or ImageScan, see the CVE triage workflow in Triaging and Remediating CVEs.

Policy not defined in Tanzu Developer Portal

If you encounter No policy has been defined, it might be because Tanzu Developer Portal is unable to view the Scan Policy resource. For example, the scanPolicy in the scan matches the name of the Scan Policy.

Confirm that the Scan Policy associated with a SourceScan or ImageScan exists by running:

kubectl describe sourcescan NAME -n DEV-NAMESPACE
kubectl describe imagescan NAME -n DEV-NAMESPACE
kubectl get scanpolicy NAME -n DEV-NAMESPACE

Where DEV-NAMESPACE is the name of the developer namespace you want to use.

Add the app.kubernetes.io/part-of label to the Scan Policy. For more information, see Enable Tanzu Developer Portal to view the ScanPolicy resource.

Lookup error when connecting to SCST - Store

If your scan pod is failing, you might see the following connection error in the logs:

dial tcp: lookup metadata-store-app.metadata-store.svc.cluster.local on 10.100.0.10:53: no such host

A connection error while attempting to connect to the local cluster URL causes this error. If this is a multicluster deployment, set the grype.metadataStore.url property in your Build profile values.yaml file. You must set the ingress domain of SCST - Store, which is deployed in the View cluster. For information about this configuration, see Configure Grype in the Build profile values file.

SourceScan error with SCST - Store endpoint without a prefix

If your SourceScan resource is failing, the status might show this error:

Error: endpoint require 'http://' or 'https://' prefix

This is because the grype.metadataStore.url value in the Tanzu Application Platform profile values.yaml file was not configured with the correct prefix. Verify that the URL starts with http:// or https://.

Deprecated pre-v1.2 templates

If the scan phase is in Error and the status condition message is:

Summary logs could not be retrieved: . error opening stream pod logs reader: container summary is \
not valid for pod scan-grypeimagescan-sample-public-zmj2g-hqv5g

this error might be a consequence of using Grype Scanner ScanTemplates shipped with SCST - Scan v1.1 or earlier. These ScanTemplates are deprecated and are not supported in Tanzu Application Platform v1.4.0 and later.

There are two options to resolve this issue:

Option 1: Upgrade to the latest Grype Scanner version. This automatically replaces the old ScanTemplates with the upgraded ScanTemplates.
Option 2: Create a ScanTemplate by following the steps in Create a scan template.

Incorrectly configured self-signed certificate

The following error in the pod logs indicate that the self-signed certificate might be incorrectly configured:

x509: certificate signed by unknown authority

To resolve this issue, ensure that shared.ca_cert_data contains the required certificate. For an example of setting up the shared self-signed certificate, see Build profile.

For information about shared.ca_cert_data, see View possible configuration settings for your package.

Unable to pull scan controller and scanner images from a specified registry

The docker field and related sub-fields by SCST - Scan Controller, Grype Scanner, or Snyk Scanner are deprecated in Tanzu Application Platform v1.4.0 and removed in Tanzu Application Platform v1.12.1. Previously these fields might be used to populate the registry-credentials secret. You might encounter the following error during installation:

UNAUTHORIZED: unauthorized to access repository

The recommended migration path for users setting up their namespaces manually is to add registry credentials to both the developer namespace and the scan-link-system namespace, using these instructions.

Important
This step does not apply to users who used --export-to-all-namespaces when setting up the Tanzu Application Platform package repository.

Grype database not available

Before running a scan, the Grype scanner downloads a copy of its database. If the database fails to download, the following log entry might appear.

Vulnerability DB [no update available] New version of grype is available: 0.50.2 [0000] WARN unable \
to check for vulnerability database update 1 error occurred: * failed to load vulnerability db: \
vulnerability database is corrupt (run db update to correct): database metadata not found: \
~/Library/Caches/grype/db/3

To resolve this issue, ensure that Grype has access to its vulnerability database:

If you set up a mirror of the vulnerability database in Use vulnerability scanning in offline and air-gapped environments, verify that it is populated and reachable.
If you did not set up a mirror, Grype manages its database behind the scenes. Verify that the cluster has access to https://anchore.com/.

This issue is unrelated to SCST – Store.

A Scanner Pod restarts once in SCST - Scan v1.5.0 or later

For SCST - Scan v1.5.0 or later, you see scanner pods restart:

Pods
   NAME                                  READY   STATUS      RESTARTS   AGE
   my-scan-45smk-pod                     0/9     Completed   1          14m

One restart in scanner pods is expected with successful scans. To support Tanzu Service Mesh (TSM) integration, jobs were replaced with TaskRuns. This restart is an artifact of how Tekton cleans up sidecar containers by patching the container specifications.

Reconciliation of SCST - Scan fails when upgrading to v1.12

When upgrading the SCST - Scan from a previous version to v1.12, you might see a reconciliation failure similar to:

NAME                                PACKAGE-NAME                                         PACKAGE-VERSION                STATUS
scanning                            scanning.apps.tanzu.vmware.com                       1.12.1-build.36081392+c072d305  Reconcile failed

If you get the package by running

tanzu package installed get scanning -n tap-install

you might see an error similar to:

STATUS:                  Reconcile failed
CONDITIONS:              - type: ReconcileFailed
  status: "True"
  reason: ""
  message: Error (see .status.usefulErrorMessage for details)
USEFUL-ERROR-MESSAGE:    ytt: Error: Overlaying data values (in following order: additional data values):
One or more data values were invalid
====================================Given data value is not declared in schema
values.yaml:
    |
  2 |   url: ""
    |    = found: url
    = expected: a map item with the key named "exports" (from .ytt/data.yaml:52)

This is because the field scanning.metadataStore.url is removed. If this field is in the tap-values.yaml file provided for the upgrade, the reconciliation fails. To resolve this problem, remove the field from the values file and run the upgrade command again.

Scanning in a cluster with restricted Kubernetes Pod Security Standards

As part of compliance with the restricted profile Kubernetes Pod Security Standards, you must set the securityContext of containers and initContainers. This applies to the prepare initContainers created by Tekton. When a pod does not meet pod Security Standards, it is not created and vulnerability scanning cannot proceed. For more information, see the Kubernetes documentation.

You might see an error message similar to the following when describing the TaskRun:

"scan-source-scan-with-passing-policy-zx46t-pod" is forbidden: violates PodSecurity "restricted:latest": \
allowPrivilegeEscalation != false (container "prepare" must set securityContext.allowPrivilegeEscalation=false), \
unrestricted capabilities (container "prepare" must set securityContext.capabilities.drop=["ALL"]), \
seccompProfile (pod or container "prepare" must set securityContext.seccompProfile.type to \
"RuntimeDefault" or "Localhost"). Maybe invalid TaskSpec. ScanPodError PodNotFound: no pod found

Edit your Tekton Pipelines package configuration in your tap-values.yaml file with the following changes:
```
tekton_pipelines:
    feature_flags:
        set_security_context: "true"
```
By setting the securityContext you resolve the prepare initContainer violation.
Update your Tanzu Application Platform installation by running:
```
tanzu package installed update tap -p tap.tanzu.vmware.com -v TAP-VERSION  --values-file \
tap-values.yaml -n tap-install
```
Where TAP-VERSION is the version of Tanzu Application Platform installed.
Run the scan again.