Anchore Kubernetes Inventory

anchore-k8s-inventory polls the Kubernetes API on an interval to retrieve which images are currently in use.

It can be run inside a cluster (under a Service Account) or outside (via any provided kubeconfig).

Getting Started

Install the binary or Download the Docker image

Installation

anchore-k8s-inventory can be run as a CLI, Docker Container, or Helm Chart

By default, anchore-k8s-inventory will look for a kubeconfig in the home directory to use to authenticate (when run as a CLI).

CLI

$ anchore-k8s-inventory --verbose-inventory-reports
{
  "cluster_name": "docker-desktop",
  "containers": [
    {
      "id": "docker://911d2cf6351cbafc349f131aeef1b1fb295a889504d38c89a065da1a91d828b9",
      "image_digest": "sha256:76049887f07a0476dc93efc2d3569b9529bf982b22d29f356092ce206e98765c",
      "image_tag": "docker.io/kubernetesui/metrics-scraper:v1.0.8",
      "name": "dashboard-metrics-scraper",
      "pod_uid": "c5b40099-20a5-4b46-8062-cf84f9d6ac23"
    },
    {
      "id": "docker://a9cd75ad99dd4363bbd882b40e753b58c62bfd7b03cabeb764c1dac97568ad26",
      "image_digest": "sha256:2e500d29e9d5f4a086b908eb8dfe7ecac57d2ab09d65b24f588b1d449841ef93",
      "image_tag": "docker.io/kubernetesui/dashboard:v2.7.0",
      "name": "kubernetes-dashboard",
      "pod_uid": "72ba7e4e-6e35-48c0-bff7-558a525074d5"
    },
	.....
  ],
  "namespaces": [
    {
      "labels": {
        "kubernetes.io/metadata.name": "kube-public"
      },
      "name": "kube-public",
      "uid": "dd561bf1-11ff-4381-8a1f-f156c206fe13"
    },
    {
      "labels": {
        "kubernetes.io/metadata.name": "kube-system"
      },
      "name": "kube-system",
      "uid": "012ebe67-dd49-4fd9-b604-258385df3957"
    },
	.....
  ],
  "nodes": [
    {
      "annotations": {
        "kubeadm.alpha.kubernetes.io/cri-socket": "unix:///var/run/cri-dockerd.sock",
        "node.alpha.kubernetes.io/ttl": "0",
        "volumes.kubernetes.io/controller-managed-attach-detach": "true"
      },
      "arch": "arm64",
      "container_runtime_version": "docker://20.10.23",
      "kernel_version": "5.15.49-linuxkit",
      "kube_proxy_version": "v1.26.1",
      "kubelet_version": "v1.26.1",
      "labels": {
        "beta.kubernetes.io/arch": "arm64",
        "beta.kubernetes.io/os": "linux",
        "kubernetes.io/arch": "arm64",
        "kubernetes.io/hostname": "minikube",
        "kubernetes.io/os": "linux",
        "minikube.k8s.io/commit": "ddac20b4b34a9c8c857fc602203b6ba2679794d3",
        "minikube.k8s.io/name": "minikube",
        "minikube.k8s.io/primary": "true",
        "minikube.k8s.io/updated_at": "2023_04_11T11_20_54_0700",
        "minikube.k8s.io/version": "v1.29.0",
        "node-role.kubernetes.io/control-plane": "",
        "node.kubernetes.io/exclude-from-external-load-balancers": ""
      },
      "name": "minikube",
      "operating_system": "linux",
      "uid": "b8334e25-68a5-4cbc-bf7a-fc188f2c6023"
    }
  ],
  "pods": [
    {
      "annotations": {
        "seccomp.security.alpha.kubernetes.io/pod": "runtime/default"
      },
      "labels": {
        "k8s-app": "dashboard-metrics-scraper",
        "pod-template-hash": "5c6664855"
      },
      "name": "dashboard-metrics-scraper-5c6664855-s8lpc",
      "namespace_uid": "c1d98ff5-6689-4016-aef3-8802790c3b10",
      "node_uid": "b8334e25-68a5-4cbc-bf7a-fc188f2c6023",
      "uid": "c5b40099-20a5-4b46-8062-cf84f9d6ac23"
    },
    {
      "labels": {
        "gcp-auth-skip-secret": "true",
        "k8s-app": "kubernetes-dashboard",
        "pod-template-hash": "55c4cbbc7c"
      },
      "name": "kubernetes-dashboard-55c4cbbc7c-6p28m",
      "namespace_uid": "c1d98ff5-6689-4016-aef3-8802790c3b10",
      "node_uid": "b8334e25-68a5-4cbc-bf7a-fc188f2c6023",
      "uid": "72ba7e4e-6e35-48c0-bff7-558a525074d5"
    },
	.....
  ],
  "serverVersionMetadata": {
    "major": "1",
    "minor": "26",
    "gitVersion": "v1.26.1",
    "gitCommit": "8f94681cd294aa8cfd3407b8191f6c70214973a4",
    "gitTreeState": "clean",
    "buildDate": "2023-01-18T15:51:25Z",
    "goVersion": "go1.19.5",
    "compiler": "gc",
    "platform": "linux/arm64"
  },
  "timestamp": "2023-05-03T12:34:13Z"
}

Container

In order to run anchore-k8s-inventory as a container, it needs a kubeconfig

~ docker run -it --rm -v ~/.kube/config:/.kube/config anchore/k8s-inventory:latest --verbose-inventory-reports

Helm Chart

Anchore-k8s-inventory is the foundation of Anchore Enterprise's Runtime Inventory feature. Running anchore-k8s-inventory via Helm is a great way to retrieve your Kubernetes Image inventory without providing Cluster Credentials to Anchore.

Anchore-k8s-inventory runs as a read-only service account in the cluster it's deployed to.

In order to report the inventory to Anchore, anchore-k8s-inventory does require authentication material for your Anchore Enterprise deployment. anchore-k8s-inventory's helm chart automatically creates a kubernetes secret for the Anchore Password based on the values file you use, Ex.:

anchore-k8s-inventory:
  anchore:
    password: foobar

It will set the following environment variable based on this: ANCHORE_K8S_INVENTORY_ANCHORE_PASSWORD=foobar.

If you don't want to store your Anchore password in the values file, you can create your own secret to do this:

apiVersion: v1
kind: Secret
metadata:
  name: anchore-k8s-inventory-anchore-password
type: Opaque
stringData:
  ANCHORE_K8S_INVENTORY_ANCHORE_PASSWORD: foobar

and then provide it to the helm chart via the values file:

anchore-k8s-inventory:
  existingSecret: anchore-k8s-inventory-anchore-password

anchore-k8s-inventory's helm chart is part of the charts.anchore.io repo. You can install it via:

helm repo add anchore https://charts.anchore.io
helm install <release-name> -f <values.yaml> anchore/k8s-inventory

A basic values file can always be found here

The anchore-k8s-inventory agent as an Enterprise Integration

In the Enterprise v5.11.0 release, Enterprise provides the ability for k8s-inventory to register and provide health reporting. This allows Enterprise to track the status of the agents and expose that information to administrators. In the API that Enterprise provides for this feature, the entities are referred to as Integrations. Hence, the anchore-k8s-inventory agent is a type of Integration.

Before an agent can start sending health reports, it needs to register with Enterprise. This is a handshake whereby the agent presents itself to Enterprise. The registration contains information such as type of integration, its name, when it was started, uptime, how often it will send health reports etc. Some of the properties are optional such as the 'description' property.

When the agent registers it is assigned an integration uuid by Enterprise. This uuid is then used for all API operations that target that particular integration instance. Hence, when the agent sends its health reports to Enterprise, it makes a REST API call to a URL that includes the integration uuid.

Registering as integration

When the agent registers with Enterprise, the registration will include a registration_id and a registration_instance_id. These are used by Enterprise to look up the integration uuid for the agent. If it is the first time the agent registers, no integration uuid will exist so Enterprise will create one and store the association between the integration uuid and <registration_id, registration_instance_id> in its database. For subsequent re-registrations (e.g., if the agent pod is restarted), the association will allow Enterprise to return the integration uuid created in the earlier registration. Hence, as long as the <registration_id, registration_instance_id> pair remains the same, Enterprise will consider it to be the same integration instance. The reason a value pair is needed is that integrations like the anchore_k8s_inventory agent can be deployed as multiple replicas (in the case of K8s Deployment). Enterprise must be able to differentiate between the agent replica instances. A value pair with sensibly chosen values makes that possible.

The registration_id can be set via configuration (see the Configuration section below).

Only the agent itself can set the registration_instance_id value. It will set it to the hostname where the agent runs (or if its empty, generate a uuid and use that value).

Backwards compatibility

If the agent interacts with an Enterprise deployment that does not support Integration registration and health reporting (i.e., Enterprise releases < v5.11.0), it will skip registration, disable health reporting and then let inventory reporting continue like in pre-v1.7.0 releases. The agent will periodically check if Enterprise has been upgraded to v5.11.0 or later and perform registration and enable health reporting in such cases. No restart of the agent is required for this to happen.

Configuration

# same as -q ; suppress all output (except for the inventory results)
quiet: false

log:
  # use structured logging
  structured: false

  # the log level; note: detailed logging suppress the ETUI
  level: "debug"

  # location to write the log file (default is not to have a log file)
  file: "./anchore-k8s-inventory.log"

# enable/disable checking for application updates on startup
check-for-app-update: true

kubeconfig:
  path:
  cluster: docker-desktop
  cluster-cert:
  server:  # ex. https://kubernetes.docker.internal:6443
  user:
    type:  # valid: [private_key, token]
    client-cert:
    private-key:
    token:

# enable/disable printing inventory reports to stdout
verbose-inventory-reports: false

Integration registration

Configure values for the registration of the agent as an Integration. The registration_id can preferably be left empty if the Anchore helm chartsk8s-inventory v0.5.0 or later are used. If explicitly set in the configuration it is advisable to use some tool that can generate uuids to ensure uniqueness.

anchore-registration:
  # The id to register the agent as with Enterprise, so Enterprise can map the agent to its integration uuid.
  # If left unspecified, the agent will attempt to set registration-id to the uid of the K8s Deployment for the agent.
  # If that fails (e.g., if the agent is not deployed on K8s), the agent will generate a UUID to use as registration-id.
  registration-id:
  # The name that the agent should have. If left unspecified, the agent will attempt to set it to the name of the K8s
  # Deployment for the agent. If that fails it will be empty.
  integration-name:
  # A short description for the agent
  integration-description:

Namespace selection

Configure which namespaces anchore-k8s-inventory should search.

• include section
  • A list of explicit strings that will detail the list of namespaces to capture image data from.
  • If left as an empty list [] all namespaces will be searched
  • Example:

namespace-selectors:
  include:
  - default
  - kube-system
  - prod-app

• exclude section
  • A list of explicit strings and/or regex patterns for namespaces to be excluded.
  • A regex is determined if the string does not match standard DNS name requirements.
  • Example:

namespace-selectors:
  exclude:
  - default
  - ^kube-*
  - ^prod-*

# Which namespaces to search or exclude.
namespace-selectors:
  # Namespaces to include as explicit strings, not regex
  # NOTE: Will search ALL namespaces if left as an empty array
  include: []

  # List of namespaces to exclude, can use explicit strings and/or regexes.
  # For example
  #
  # list:
  # - default
  # - ^kube-*
  #
  # Will exclude the default, kube-system, and kube-public namespaces
  exclude: []

  # If true then namespaces containing 0 pods will be omitted from the report sent to Anchore Enterprise
  ignore-empty: false

Account Routing

The following configuration options can determine which Anchore account inventory reports are sent to. Without any of the following configuration the account set in the anchore section will be used.

If a mixture of static account routing and account routing by namespace label is used then the static account routes configured in k8s-inventory config will take precedence over any account that is specified by namespace label.

Static account routing config

Set a list of accounts and which namespaces inventory should be sent to that account. You can override the default credentials on a per account basis, if not set then the global credentials set in the anchore section will be used.

account-routes:
   # <Anchore Account Name>: # (this is the name of the anchore account e.g. admin)
   #   user: <username> <OPTIONAL>
   #   password: <password> <OPTIONAL>
   #   namespaces: # Can be a list of explicit namespaces matches or regex patterns
   #     - <namespace>
   #     - <regex pattern>
   #
   # Example
   # admin:
   #   user: username
   #   password: password
   #   namespaces:
   #     - default
   #     - ^kube-*

Account routing by namespace label

In this mode use a label set on a kubernetes namespace to determine which Anchore account inventory data for that namespace should be sent to. It is assumed that the credentials set in the anchore section can post to all accounts.

# Route namespaces to anchore accounts by a label on the namespace
account-route-by-namespace-label:
  # The name of the namespace label that will be used to route the contents of
  # that namespace to the Anchore account matching the value of the label
  key:  # e.g anchore.io/account.name
  # The name of the account to route inventory to for a namespace that is
  # missing the label or if the anchore account is not found.
  # If not set then it will default to the account specified in the anchore credentials
  default-account:  # e.g. admin
  # If true will exclude inventorying namespaces that are missing the specified label
  ignore-namespace-missing-label: false

Kubernetes API Parameters

This section will allow users to tune the way anchore-k8s-inventory interacts with the kubernetes API server.

# Kubernetes API configuration parameters (should not need tuning)
kubernetes:
  # Sets the request timeout for kubernetes API requests
  request-timeout-seconds: 60

  # Sets the number of objects to iteratively return when listing resources
  request-batch-size: 100

  # Worker pool size for collecting pods from namespaces. Adjust this if the api-server gets overwhelmed
  worker-pool-size: 100

anchore-k8s-inventory mode of operation

# Can be one of adhoc, periodic (defaults to adhoc)
mode: adhoc

# Only respected if mode is periodic
polling-interval-seconds: 300

Missing Tag Policy

There are cases where images in Kubernetes do not have an associated tag - for example when an image is deployed using the digest.

kubectl run python --image=python@sha256:f0a210a37565286ecaaac0529a6749917e8ea58d3dfc72c84acfbfbe1a64a20a

Anchore Enterprise will use the image digest to process an image but it still requires a tag to be associated with the image. The missing-tag-policy lets you configure the best way to handle the missing tag edge case in your environment.

digest will use the image digest as a dummy tag.

{
  "tag": "alpine:4ed1812024ed78962a34727137627e8854a3b414d19e2c35a1dc727a47e16fba",
  "repoDigest": "sha256:4ed1812024ed78962a34727137627e8854a3b414d19e2c35a1dc727a47e16fba"
}

insert will use a dummy tag configured by missing-tag-policy.tag

{
  "tag": "alpine:UNKNOWN",
  "repoDigest": "sha256:4ed1812024ed78962a34727137627e8854a3b414d19e2c35a1dc727a47e16fba"
}

drop will simply ignore the images that don't have tags.

# Handle cases where a tag is missing. For example - images designated by digest
missing-tag-policy:
  # One of the following options [digest, insert, drop]. Default is 'digest'
  #
  # [digest] will use the image's digest as a dummy tag.
  #
  # [insert] will insert a default tag in as a dummy tag. The dummy tag is
  #          customizable under missing-tag-policy.tag
  #
  # [drop] will drop images that do not have tags associated with them. Not
  #        recommended.
  policy: digest

  # Dummy tag to use. Only applicable if policy is 'insert'. Defaults to UNKNOWN
  tag: UNKNOWN

Ignore images that are not yet in a Running state

# Ignore images out of pods that are not in a Running state
ignore-not-running: true

Batching Inventory Report Posting

Set upper limits for the content that can be contained in a single inventory report POST to Anchore Enterprise. If the inventory data is greater than the limit then the inventory report will be broken into smaller requests up to the limit size specified.

inventory-report-limits:
    namespaces: 0 # default of 0 means no limit

Metadata configuration

Include only a subset of annotations/labels for each resource type or disable metadata entirely

metadata-collection:
  nodes:
    annotations: [] # List of annotations to include (explicit or regex)
    labels: [] # List of labels to include (explicit or regex)
    disable: false # Remove all optional node metadata from the inventory report
  namespaces:
    annotations: [] # List of annotations to include (explicit or regex)
    labels: [] # List of labels to include (explicit or regex)
    disable: false # Remove all optional namespace metadata from the inventory report
  pods:
    annotations: [] # List of annotations to include (explicit or regex)
    labels: [] # List of labels to include (explicit or regex)
    disable: false # Remove all optional pod metadata from the inventory report

Anchore API configuration

Use this section to configure the Anchore Enterprise API endpoint

anchore:
  url: <your anchore api url>
  user: <anchore-k8s-inventory_inventory_user>
  password: $ANCHORE_K8S_INVENTORY_ANCHORE_PASSWORD
  account: <anchore account to send inventory reports>
  http:
    insecure: true
    timeout-seconds: 10

Support for Integration registration and health reporting (v1.7.0)

From v1.7.0, anchore-k8s-inventory will attempt to register as an integration with Enterprise and send health reports to allow Enterprise to track its status. This requires Enterprise release v5.11.0 or later but the agent will work with older versions of Enterprise. However, it will only perform the inventory reporting with those Enterprise deployments.

Behavior change (v0.5.0) (formerly KAI)

In versions of anchore-k8s-inventory < v0.5.0 the default behavior was to output the inventory report to stdout every time it was generated. anchore-k8s-inventory v0.5.0 changes this so it will not print to stdout unless verbose-inventory-reports: true is set in the config file or anchore-k8s-inventory is called with the --verbose-inventory-reports flag.

Configuration Changes (v0.2.2 -> v0.3.0) (formerly KAI)

There are a few configurations that were changed from v0.2.2 to v0.3.0

kubernetes-request-timeout-seconds

The request timeout for the kubernetes API was changed from

kubernetes-request-timeout-seconds: 60

to

kubernetes:
  request-timeout-seconds: 60

anchore-k8s-inventory will still honor the old configuration. It will prefer the old configuration parameter until it is removed from the config entirely. It is safe to remove the old configuration in favor of the new config.

namespaces

The namespace configuration was changed from

namespaces:
- all

to

namespace-selectors:
  include: []
  exclude: []

namespace-selectors was added to eventually replace namespaces to allow for both include and exclude configs. The old namespaces array will be honored if namespace-selectors.include is empty. It is safe to remove namespaces entirely in favor of namespace-selectors

Developing

Build

Note: This will drop the binary in the ./snapshot/ directory

On Mac

make mac-binary

On Linux

make linux-binary

Testing

The Makefile has testing built into it. For unit tests simply run

make unit

Docker

To build a docker image, you'll need to provide a kubeconfig.

Note: Docker build requires files to be within the docker build context

docker build -t localhost/anchore-k8s-inventory:latest --build-arg KUBECONFIG=./kubeconfig .

Shell Completion

anchore-k8s-inventory comes with shell completion for specifying namespaces, it can be enabled as follows. Run with the --help command to get the instructions for the shell of your choice

anchore-k8s-inventory completion <zsh|bash|fish>

Using Skaffold

You can use skaffold for dev. The 'bootstrap-skaffold' make target will clone the chart into the current directory to wire it up for skaffold to use. To trigger redeployments you'll need to run make linux-binary and skaffold will rebuild the image and update the helm release.

make bootstrap-skaffold
make linux-binary
skaffold dev

Releasing

To create a release of anchore-k8s-inventory, a tag needs to be created that points to a commit in main that we want to release. This tag shall be a semver prefixed with a v, e.g. v0.2.7. This will trigger a GitHub Action that will create the release.

After the release has been successfully created, make sure to specify the updated version in both Enterprise and the anchore-k8s-inventory Helm Chart in anchore-charts.