Skip to content

Commit

Permalink
Add falco service k8s (#496)
Browse files Browse the repository at this point in the history
* Add falco service to k8s install/update labels

Update the instructions for K8s RBAC installation to also create a
service that maps to port 8765 of the falco pod. This allows other
services to access the embedded webserver within falco.

Also clean up the set of labels to use a consistent app: falco-example,
role:security for each object.

* Cange K8s Audit Example to use falco daemonset

Change the K8s Audit Example instructions to use minikube in conjunction
with a falco daemonset running inside of minikube. (We're going to start
prebuilding kernel modules for recent minikube variants to make this
possible).

When running inside of minikube in conjunction with a service, you have
to go through some additional steps to find the ClusterIP associated
with the falco service and use that ip when configuring the k8s audit
webhook. Overall it's still a more self-contained set of instructions,
though.
  • Loading branch information
mstemm authored Jan 17, 2019
1 parent 6863675 commit 889fcc8
Show file tree
Hide file tree
Showing 6 changed files with 58 additions and 13 deletions.
25 changes: 20 additions & 5 deletions examples/k8s_audit_config/README.md
Original file line number Diff line number Diff line change
Expand Up @@ -3,21 +3,36 @@
The files in this directory can be used to configure k8s audit logging. The relevant files are:

* [audit-policy.yaml](./audit-policy.yaml): The k8s audit log configuration we used to create the rules in [k8s_audit_rules.yaml](../../rules/k8s_audit_rules.yaml). You may find it useful as a reference when creating your own K8s Audit Log configuration.
* [webhook-config.yaml](./webhook-config.yaml): A webhook configuration that sends audit events to localhost, port 8765. You may find it useful as a starting point when deciding how to route audit events to the embedded webserver within falco.
* [webhook-config.yaml.in](./webhook-config.yaml.in): A (templated) webhook configuration that sends audit events to an ip associated with the falco service, port 8765. It is templated in that the *actual* ip is defined in an environment variable `FALCO_SERVICE_CLUSTERIP`, which can be plugged in using a program like `envsubst`. You may find it useful as a starting point when deciding how to route audit events to the embedded webserver within falco.

This file is only needed when using Minikube, which doesn't currently
These files are only needed when using Minikube, which doesn't currently
have the ability to provide an audit config/webhook config directly
from the minikube commandline. See [this issue](https://github.com/kubernetes/minikube/issues/2741) for more details.

* [apiserver-config.patch.sh](./apiserver-config.patch.sh): A script that changes the configuration file `/etc/kubernetes/manifests/kube-apiserver.yaml` to add necessary config options and mounts for the kube-apiserver container that runs within the minikube vm.

A way to use these files with minikube to enable audit logging would be to run the following commands, from this directory:
A way to use these files with minikube to run falco and enable audit logging would be the following:

#### Start Minikube with Audit Logging Enabled

Run the following to start minikube with Audit Logging Enabled:

```
minikube start --kubernetes-version v1.11.0 --mount --mount-string $PWD:/tmp/k8s_audit_config --feature-gates AdvancedAuditing=true
```

#### Create a Falco DaemonSet and Supporting Accounts/Services

Follow the [K8s Using Daemonset](../../integrations/k8s-using-daemonset/README.md) instructions to create a falco service account, service, configmap, and daemonset.

#### Configure Audit Logging with a Policy and Webhook

Run the following commands to fill in the template file with the ClusterIP ip address you created with the `falco-service` service above, and configure audit logging to use a policy and webhook that directs the right events to the falco daemonset. Although services like `falco-service.default.svc.cluster.local` can not be resolved from the kube-apiserver container within the minikube vm (they're run as pods but not *really* a part of the cluster), the ClusterIPs associated with those services are routable.

```
FALCO_SERVICE_CLUSTERIP=$(kubectl get service falco-service -o=jsonpath={.spec.clusterIP}) envsubst < webhook-config.yaml.in > webhook-config.yaml
ssh -i $(minikube ssh-key) docker@$(minikube ip) sudo bash /tmp/k8s_audit_config/apiserver-config.patch.sh
ssh -i $(minikube ssh-key) -R 8765:localhost:8765 docker@$(minikube ip)
```

K8s audit events will then be sent to localhost on the host (not minikube vm) machine, port 8765.
K8s audit events will then be routed to the falco daemonset within the cluster, which you can observe via `kubectl logs -f $(kubectl get pods -l app=falco-example -o jsonpath={.items[0].metadata.name})`.

Original file line number Diff line number Diff line change
Expand Up @@ -3,7 +3,7 @@ kind: Config
clusters:
- name: falco
cluster:
server: http://127.0.0.1:8765/k8s_audit
server: http://$FALCO_SERVICE_CLUSTERIP:8765/k8s_audit
contexts:
- context:
cluster: falco
Expand Down
13 changes: 11 additions & 2 deletions integrations/k8s-using-daemonset/README.md
Original file line number Diff line number Diff line change
Expand Up @@ -4,7 +4,7 @@ This directory gives you the required YAML files to stand up Sysdig Falco on Kub

The two options are provided to deploy a Daemon Set:
- `k8s-with-rbac` - This directory provides a definition to deploy a Daemon Set on Kubernetes with RBAC enabled.
- `k8s-without-rbac` - This directory provides a definition to deploy a Daemon Set on Kubernetes without RBAC enabled.
- `k8s-without-rbac` - This directory provides a definition to deploy a Daemon Set on Kubernetes without RBAC enabled. **This method is deprecated in favor of RBAC-based installs, and won't be updated going forward.**

Also provided:
- `falco-event-generator-deployment.yaml` - A Kubernetes Deployment to generate sample events. This is useful for testing, but note it will generate a large number of events.
Expand All @@ -21,11 +21,20 @@ clusterrolebinding "falco-cluster-role-binding" created
k8s-using-daemonset$
```

We also create a service that allows other services to reach the embedded webserver in falco, which listens on https port 8765:

```
k8s-using-daemonset$ kubectl create -f k8s-with-rbac/falco-service.yaml
service/falco-service created
k8s-using-daemonset$
```

The Daemon Set also relies on a Kubernetes ConfigMap to store the Falco configuration and make the configuration available to the Falco Pods. This allows you to manage custom configuration without rebuilding and redeploying the underlying Pods. In order to create the ConfigMap you'll need to first need to copy the required configuration from their location in this GitHub repo to the `k8s-with-rbac/falco-config/` directory. Any modification of the configuration should be performed on these copies rather than the original files.

```
k8s-using-daemonset$ cp ../../falco.yaml k8s-with-rbac/falco-config/
k8s-using-daemonset$ cp ../../rules/falco_rules.* k8s-with-rbac/falco-config/
k8s-using-daemonset$ cp ../../rules/k8s_audit_rules.yaml k8s-with-rbac/falco-config/
```

If you want to send Falco alerts to a Slack channel, you'll want to modify the `falco.yaml` file to point to your Slack webhook. For more information on getting a webhook URL for your Slack team, refer to the [Slack documentation](https://api.slack.com/incoming-webhooks). Add the below to the bottom of the `falco.yaml` config file you just copied to enable Slack messages.
Expand Down Expand Up @@ -54,7 +63,7 @@ k8s-using-daemonset$
```


## Deploying to Kubernetes without RBAC enabled
## Deploying to Kubernetes without RBAC enabled (**Deprecated**)

If you are running Kubernetes with Legacy Authorization enabled, you can use `kubectl` to deploy the Daemon Set provided in the `k8s-without-rbac` directory. The example provides the ability to post messages to a Slack channel via a webhook. For more information on getting a webhook URL for your Slack team, refer to the [Slack documentation](https://api.slack.com/incoming-webhooks). Modify the [`args`](https://github.com/draios/falco/blob/dev/examples/k8s-using-daemonset/falco-daemonset.yaml#L21) passed to the Falco container to point to the appropriate URL for your webhook.

Expand Down
Original file line number Diff line number Diff line change
Expand Up @@ -2,11 +2,17 @@ apiVersion: v1
kind: ServiceAccount
metadata:
name: falco-account
labels:
app: falco-example
role: security
---
kind: ClusterRole
apiVersion: rbac.authorization.k8s.io/v1beta1
metadata:
name: falco-cluster-role
labels:
app: falco-example
role: security
rules:
- apiGroups: ["extensions",""]
resources: ["nodes","namespaces","pods","replicationcontrollers","services","events","configmaps"]
Expand All @@ -19,6 +25,9 @@ apiVersion: rbac.authorization.k8s.io/v1beta1
metadata:
name: falco-cluster-role-binding
namespace: default
labels:
app: falco-example
role: security
subjects:
- kind: ServiceAccount
name: falco-account
Expand Down
Original file line number Diff line number Diff line change
@@ -1,16 +1,15 @@
apiVersion: extensions/v1beta1
kind: DaemonSet
metadata:
name: falco
name: falco-daemonset
labels:
name: falco-daemonset
app: demo
app: falco-example
role: security
spec:
template:
metadata:
labels:
name: falco
app: demo
app: falco-example
role: security
spec:
serviceAccount: falco-account
Expand Down
13 changes: 13 additions & 0 deletions integrations/k8s-using-daemonset/k8s-with-rbac/falco-service.yaml
Original file line number Diff line number Diff line change
@@ -0,0 +1,13 @@
kind: Service
apiVersion: v1
metadata:
name: falco-service
labels:
app: falco-example
role: security
spec:
selector:
app: falco-example
ports:
- protocol: TCP
port: 8765

0 comments on commit 889fcc8

Please sign in to comment.