122 lines
5.0 KiB
Markdown
122 lines
5.0 KiB
Markdown
---
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reviewers:
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- soltysh
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- sttts
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- ericchiang
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content_template: templates/concept
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title: Auditing with Falco
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---
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{{% capture overview %}}
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### Use Falco to collect audit events
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[Falco](https://falco.org/) is an open source project for intrusion and abnormality detection for Cloud Native platforms.
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This section describes how to set up Falco, how to send audit events to the Kubernetes Audit endpoint exposed by Falco, and how Falco applies a set of rules to automatically detect suspicious behavior.
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{{% /capture %}}
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{{% capture body %}}
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#### Install Falco
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Install Falco by using one of the following methods:
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- [Standalone Falco][falco_installation]
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- [Kubernetes DaemonSet][falco_installation]
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- [Falco Helm Chart][falco_helm_chart]
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Once Falco is installed make sure it is configured to expose the Audit webhook. To do so, use the following configuration:
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```yaml
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webserver:
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enabled: true
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listen_port: 8765
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k8s_audit_endpoint: /k8s_audit
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ssl_enabled: false
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ssl_certificate: /etc/falco/falco.pem
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```
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This configuration is typically found in the `/etc/falco/falco.yaml` file. If Falco is installed as a Kubernetes DaemonSet, edit the `falco-config` ConfigMap and add this configuration.
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#### Configure Kubernetes Audit
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1. Create a [kubeconfig file](/docs/concepts/configuration/organize-cluster-access-kubeconfig/) for the [kube-apiserver][kube-apiserver] webhook audit backend.
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cat <<EOF > /etc/kubernetes/audit-webhook-kubeconfig
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apiVersion: v1
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kind: Config
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clusters:
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- cluster:
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server: http://<ip_of_falco>:8765/k8s_audit
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name: falco
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contexts:
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- context:
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cluster: falco
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user: ""
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name: default-context
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current-context: default-context
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preferences: {}
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users: []
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EOF
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1. Start [kube-apiserver][kube-apiserver] with the following options:
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```shell
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--audit-policy-file=/etc/kubernetes/audit-policy.yaml --audit-webhook-config-file=/etc/kubernetes/audit-webhook-kubeconfig
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```
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#### Audit Rules
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Rules devoted to Kubernetes Audit Events can be found in [k8s_audit_rules.yaml][falco_k8s_audit_rules]. If Audit Rules is installed as a native package or using the official Docker images, Falco copies the rules file to `/etc/falco/`, so they are available for use.
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There are three classes of rules.
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The first class of rules looks for suspicious or exceptional activities, such as:
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- Any activity by an unauthorized or anonymous user.
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- Creating a pod with an unknown or disallowed image.
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- Creating a privileged pod, a pod mounting a sensitive filesystem from the host, or a pod using host networking.
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- Creating a NodePort service.
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- Creating a ConfigMap containing private credentials, such as passwords and cloud provider secrets.
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- Attaching to or executing a command on a running pod.
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- Creating a namespace external to a set of allowed namespaces.
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- Creating a pod or service account in the kube-system or kube-public namespaces.
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- Trying to modify or delete a system ClusterRole.
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- Creating a ClusterRoleBinding to the cluster-admin role.
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- Creating a ClusterRole with wildcarded verbs or resources. For example, overly permissive.
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- Creating a ClusterRole with write permissions or a ClusterRole that can execute commands on pods.
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A second class of rules tracks resources being created or destroyed, including:
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- Deployments
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- Services
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- ConfigMaps
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- Namespaces
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- Service accounts
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- Role/ClusterRoles
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- Role/ClusterRoleBindings
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The final class of rules simply displays any Audit Event received by Falco. This rule is disabled by default, as it can be quite noisy.
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For further details, see [Kubernetes Audit Events][falco_ka_docs] in the Falco documentation.
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[kube-apiserver]: /docs/admin/kube-apiserver
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[auditing-proposal]: https://github.com/kubernetes/community/blob/master/contributors/design-proposals/api-machinery/auditing.md
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[auditing-api]: https://github.com/kubernetes/kubernetes/blob/{{< param "githubbranch" >}}/staging/src/k8s.io/apiserver/pkg/apis/audit/v1/types.go
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[gce-audit-profile]: https://github.com/kubernetes/kubernetes/blob/{{< param "githubbranch" >}}/cluster/gce/gci/configure-helper.sh#L735
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[kubeconfig]: /docs/tasks/access-application-cluster/configure-access-multiple-clusters/
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[fluentd]: http://www.fluentd.org/
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[fluentd_install_doc]: https://docs.fluentd.org/v1.0/articles/quickstart#step-1:-installing-fluentd
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[fluentd_plugin_management_doc]: https://docs.fluentd.org/v1.0/articles/plugin-management
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[logstash]: https://www.elastic.co/products/logstash
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[logstash_install_doc]: https://www.elastic.co/guide/en/logstash/current/installing-logstash.html
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[kube-aggregator]: /docs/concepts/api-extension/apiserver-aggregation
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[falco_website]: https://www.falco.org
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[falco_k8s_audit_rules]: https://github.com/falcosecurity/falco/blob/master/rules/k8s_audit_rules.yaml
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[falco_ka_docs]: https://falco.org/docs/event-sources/kubernetes-audit
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[falco_installation]: https://falco.org/docs/installation
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[falco_helm_chart]: https://github.com/helm/charts/tree/master/stable/falco
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{{% /capture %}}
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