Sysdig Falco

Sysdig Falco is a behavioral activity monitor designed to detect anomalous activity in your applications. You can use Falco to monitor run-time security of your Kubernetes applications and internal components.

To know more about Sysdig Falco have a look at:

• Kubernetes security logging with Falco & Fluentd
• Active Kubernetes security with Sysdig Falco, NATS, and kubeless
• Detecting cryptojacking with Sysdig’s Falco

Introduction

This chart adds Falco to all nodes in your cluster using a DaemonSet.

Also provides a Deployment for generating Falco alerts. This is useful for testing purposes.

Installing the Chart

To install the chart with the release name my-release run:

$ helm install --name my-release stable/falco

After a few seconds, Falco should be running.

Tip: List all releases using helm list, a release is a name used to track a specific deployment

Uninstalling the Chart

To uninstall/delete the my-release deployment:

$ helm delete my-release

Tip: Use helm delete --purge my-release to completely remove the release from Helm internal storage

The command removes all the Kubernetes components associated with the chart and deletes the release.

Configuration

The following table lists the configurable parameters of the Falco chart and their default values.

Parameter	Description	Default
image.registry	The image registry to pull from	docker.io
image.repository	The image repository to pull from	falcosecurity/falco
image.tag	The image tag to pull	0.14.0
image.pullPolicy	The image pull policy	IfNotPresent
resources.requests.cpu	CPU requested for being run in a node	100m
resources.requests.memory	Memory requested for being run in a node	512Mi
resources.limits.cpu	CPU limit	200m
resources.limits.memory	Memory limit	1024Mi
extraArgs	Specify additional container args	[]
rbac.create	If true, create & use RBAC resources	true
serviceAccount.create	Create serviceAccount	true
serviceAccount.name	Use this value as serviceAccountName
fakeEventGenerator.enabled	Run falco-event-generator for sample events	false
fakeEventGenerator.replicas	How many replicas of falco-event-generator to run	1
daemonset.updateStrategy.type	The updateStrategy for updating the daemonset	RollingUpdate
proxy.httpProxy	Set the Proxy server if is behind a firewall	``
proxy.httpsProxy	Set the Proxy server if is behind a firewall	``
proxy.noProxy	Set the Proxy server if is behind a firewall	``
ebpf.enabled	Enable eBPF support for Falco instead of falco-probe kernel module	false
ebpf.settings.hostNetwork	Needed to enable eBPF JIT at runtime for performance reasons	true
ebpf.settings.mountEtcVolume	Needed to detect which kernel version are running in Google COS	true
falco.rulesFile	The location of the rules files	[/etc/falco/falco_rules.yaml, /etc/falco/falco_rules.local.yaml, /etc/falco/rules.d]
falco.jsonOutput	Output events in json or text	false
falco.jsonIncludeOutputProperty	Include output property in json output	true
falco.logStderr	Send Falco debugging information logs to stderr	true
falco.logSyslog	Send Falco debugging information logs to syslog	true
falco.logLevel	The minimum level of Falco debugging information to include in logs	info
falco.priority	The minimum rule priority level to load and run	debug
falco.bufferedOutputs	Use buffered outputs to channels	false
falco.outputs.rate	Number of tokens gained per second	1
falco.outputs.maxBurst	Maximum number of tokens outstanding	1000
falco.syslogOutput.enabled	Enable syslog output for security notifications	true
falco.fileOutput.enabled	Enable file output for security notifications	false
falco.fileOutput.keepAlive	Open file once or every time a new notification arrives	false
falco.fileOutput.filename	The filename for logging notifications	./events.txt
falco.stdoutOutput.enabled	Enable stdout output for security notifications	true
falco.programOutput.enabled	Enable program output for security notifications	false
falco.programOutput.keepAlive	Start the program once or re-spawn when a notification arrives	false
falco.programOutput.program	Command to execute for program output	mail -s "Falco Notification" [email protected]
customRules	Third party rules enabled for Falco	{}
integrations.gcscc.enabled	Enable Google Cloud Security Command Center integration	false
integrations.gcscc.webhookUrl	The URL where sysdig-gcscc-connector webhook is listening	http://sysdig-gcscc-connector.default.svc.cluster.local:8080/events
integrations.gcscc.webhookAuthenticationToken	Token used for authentication and webhook	b27511f86e911f20b9e0f9c8104b4ec4
integrations.natsOutput.enabled	Enable NATS Output integration	false
integrations.natsOutput.natsUrl	The NATS' URL where Falco is going to publish security alerts	nats://nats.nats-io.svc.cluster.local:4222
integrations.pubsubOutput.credentialsData	Contents retrieved from `cat $HOME/.config/gcloud/legacy_credentials//adc.json	jq -c .`
integrations.pubsubOutput.enabled	Enable GCloud PubSub Output Integration	false
integrations.pubsubOutput.projectID	GCloud Project ID where the Pub/Sub will be created
integrations.snsOutput.enabled	Enable Amazon SNS Output integration	false
integrations.snsOutput.topic	The SNS topic where Falco is going to publish security alerts
integrations.snsOutput.aws_access_key_id	The AWS Access Key Id credentials for access to SNS n
integrations.snsOutput.aws_secret_access_key	The AWS Secret Access Key credential to access to SNS
integrations.snsOutput.aws_default_region	The AWS region where SNS is deployed
tolerations	The tolerations for scheduling	node-role.kubernetes.io/master:NoSchedule

Specify each parameter using the --set key=value[,key=value] argument to helm install. For example,

$ helm install --name my-release --set falco.jsonOutput=true stable/falco

Alternatively, a YAML file that specifies the values for the parameters can be provided while installing the chart. For example,

$ helm install --name my-release -f values.yaml stable/falco

Tip: You can use the default values.yaml

Loading custom rules

Falco ships with a nice default ruleset. Is a good starting point but sooner or later we are going to need to add custom rules which fits our needs.

A few days ago we published several rules for well known container images.

So the question is: How we can load custom rules in our Falco deployment?

We are going to create a file which contains custom rules so that we can keep it in a Git repository.

$ cat custom-rules.yaml

And the file looks like this one:

customRules:
  rules-traefik.yaml: |-
    - macro: traefik_consider_syscalls
      condition: (evt.num < 0)

    - macro: app_traefik
      condition: container and container.image startswith "traefik"

    # Restricting listening ports to selected set

    - list: traefik_allowed_inbound_ports_tcp
      items: [443, 80, 8080]

    - rule: Unexpected inbound tcp connection traefik
      desc: Detect inbound traffic to traefik using tcp on a port outside of expected set
      condition: inbound and evt.rawres >= 0 and not fd.sport in (traefik_allowed_inbound_ports_tcp) and app_traefik
      output: Inbound network connection to traefik on unexpected port (command=%proc.cmdline pid=%proc.pid connection=%fd.name sport=%fd.sport user=%user.name %container.info image=%container.image)
      priority: NOTICE

    # Restricting spawned processes to selected set

    - list: traefik_allowed_processes
      items: ["traefik"]

    - rule: Unexpected spawned process traefik
      desc: Detect a process started in a traefik container outside of an expected set
      condition: spawned_process and not proc.name in (traefik_allowed_processes) and app_traefik
      output: Unexpected process spawned in traefik container (command=%proc.cmdline pid=%proc.pid user=%user.name %container.info image=%container.image)
      priority: NOTICE

So next step is to use the custom-rules.yaml file for installing the Falco Helm chart.

$ helm install --name falco -f custom-rules.yaml stable/falco

And we will see in our logs something like:

Tue Jun  5 15:08:57 2018: Loading rules from file /etc/falco/rules.d/rules-traefik.yaml:

And this means that our Falco installation has loaded the rules and is ready to help us.

Automating the generation of custom-rules.yaml file

Sometimes edit YAML files with multistrings is a bit error prone, so we added a script for automating this step and make your life easier.

This script lives in falco-extras repository in the scripts directory.

Imagine that you would like to add rules for your Redis, MongoDB and Traefik containers, you have to:

$ git clone https://github.com/draios/falco-extras.git
$ cd falco-extras
$ ./scripts/rules2helm rules/rules-mongo.yaml rules/rules-redis.yaml rules/rules-traefik.yaml > custom-rules.yaml
$ helm install --name falco -f custom-rules.yaml stable/falco

And that's all, in a few seconds you will see your pods up and running with MongoDB, Redis and Traefik rules enabled.