- Features
- Tutorials and Demos
- Install operator
- Set logging verbosity
- Pull images from private registry
- Configure the SELinux type
- Restrict the allowed syscalls in seccomp profiles
- Constrain spod scheduling
- Create a seccomp profile
- Create a SELinux Profile
- Restricting to a Single Namespace
- Using metrics
- Using the log enricher
- Configuring webhooks
- Troubleshooting
- Notes on OpenShift and SCCs
- Uninstalling
The feature scope of the security-profiles-operator is right now limited to:
- Adds a
SeccompProfileCRD (alpha) to store seccomp profiles. - Adds a
ProfileBindingCRD (alpha) to bind security profiles to pods. - Adds a
ProfileRecordingCRD (alpha) to record security profiles from workloads. - Synchronize seccomp profiles across all worker nodes.
- Validates if a node supports seccomp and do not synchronize if not.
- Providing metrics endpoints
- Introduction to Seccomp and the Kubernetes Seccomp Operator (@saschagrunert and @hasheddan)
- Enhancing Kubernetes with the Security Profiles Operator (@cmurphy and @saschagrunert)
- Securing Kubernetes Applications by Crafting Custom Seccomp Profiles (@saschagrunert)
The operator container image consists of an image manifest which supports the
architectures amd64 and arm64 for now. To deploy the operator, first install
cert-manager via kubectl, if you're not running on
OpenShift:
$ kubectl apply -f https://github.com/cert-manager/cert-manager/releases/download/v1.9.1/cert-manager.yaml
$ kubectl --namespace cert-manager wait --for condition=ready pod -l app.kubernetes.io/instance=cert-managerOpenShift ships it's own CA injector which means we can skip installing cert-manager. After this step, apply the operator manifest:
$ kubectl apply -f https://raw.githubusercontent.com/kubernetes-sigs/security-profiles-operator/main/deploy/operator.yamlIt is also possible to install packages from operatorhub.io using OLM.
To be able to use the OperatorHub.io resources in OpenShift, create a new
CatalogResource like this:
apiVersion: operators.coreos.com/v1alpha1
kind: CatalogSource
metadata:
name: operatorhubio
namespace: openshift-marketplace
spec:
displayName: Community Operators
image: quay.io/operator-framework/upstream-community-operators:latest
publisher: OperatorHub.io
sourceType: grpcAfter that, the Security Profiles Operator should then be installable via OperatorHub.
To install SPO, first make sure that OLM itself is installed. Then install SPO using the provided manifest:
$ kubectl apply -f https://raw.githubusercontent.com/kubernetes-sigs/security-profiles-operator/main/examples/olm/operatorhub-io.yamlSPO would be then installed in the security-profiles-operator namespace. To troubleshoot the installation,
check the state of the Subscription, CSV and InstallPlan objects in the security-profiles-operator namespace:
$ kubectl get ip,csv,sub -nsecurity-profiles-operatorThe SPO upstream also creates bundles and catalogs for both released versions
and after every commit to the main branch. Provided that your cluster uses OLM
(see above) you can install SPO using:
$ kubectl apply -f https://raw.githubusercontent.com/kubernetes-sigs/security-profiles-operator/main/examples/olm/install-resources.yamlNote that on OpenShift, the OLM catalogs are deployed into the openshift-marketplace namespace, so you'd
need to replace the namespaces before deploying:
manifest=https://raw.githubusercontent.com/kubernetes-sigs/security-profiles-operator/main/examples/olm/install-resources.yaml
$ curl $manifest | sed "s#olm#openshift-marketplace#g" | oc apply -f -A helm chart is also available for installation. The chart is attached to each GitHub release as an artifact, and can be installed by executing the following shell commands:
# Install cert-manager if it is not already installed (TODO: The helm
# chart might do this one day - see issue 1062 for details):
kubectl apply -f https://github.com/cert-manager/cert-manager/releases/download/v1.8.0/cert-manager.yaml
kubectl --namespace cert-manager wait --for condition=ready pod -l app.kubernetes.io/instance=cert-manager
# Install the chart from a release URL (note: helm also allows users to
# specify a file path instead of a URL, if desired):
helm install security-profiles-operator https://github.com/kubernetes-sigs/security-profiles-operator/releases/download/v0.5.1-dev/security-profiles-operator-0.5.1-dev.tgzIn case you installed SPO on an AKS cluster, it is recommended to configure webhook to respect the control-plane label as follows:
$ kubectl -nsecurity-profiles-operator patch spod spod --type=merge \
-p='{"spec":{"webhookOptions":[{"name":"binding.spo.io","namespaceSelector":{"matchExpressions":[{"key":"control-plane","operator":"DoesNotExist"}]}},{"name":"recording.spo.io","namespaceSelector":{"matchExpressions":[{"key":"control-plane","operator":"DoesNotExist"}]}}]}}'Afterwards, validate spod has been patched successfully by ensuring the RUNNING state:
$ kubectl -nsecurity-profiles-operator get spod spod
NAME STATE
spod RUNNINGThe operator supports the default logging verbosity of 0 and an enhanced 1.
To switch to the enhanced logging verbosity, patch the spod config by adjusting
the value:
> kubectl -n security-profiles-operator patch spod spod --type=merge -p '{"spec":{"verbosity":1}}'
securityprofilesoperatordaemon.security-profiles-operator.x-k8s.io/spod patched
The daemon should now indicate that it's using the new logging verbosity:
> k logs --selector name=spod security-profiles-operator | head -n1
I1111 15:13:16.942837 1 main.go:182] "msg"="Set logging verbosity to 1"
The container images from spod pod can be pulled from a private registry. This can be achived by defining the imagePullSecrets
inside of the SPOD configuration.
The operator uses by default the spc_t SELinux type in the security context of the daemon pod. This can be easily
changed to a different SELinux type by patching the spod config as follows:
> kubectl -n security-profiles-operator patch spod spod --type=merge -p '{"spec":{"selinuxTypeTag":"unconfined_t"}}'
securityprofilesoperatordaemon.security-profiles-operator.x-k8s.io/spod patched
The ds/spod should now be updated by the manager with the new SELinux type, and all daemon pods recreated:
kubectl get ds spod -o yaml | grep unconfined_t -B2
runAsUser: 65535
seLinuxOptions:
type: unconfined_t
--
runAsUser: 0
seLinuxOptions:
type: unconfined_t
--
runAsUser: 0
seLinuxOptions:
type: unconfined_t
The operator doesn't restrict by default the allowed syscalls in the seccomp profiles. This means that any syscall can be allowed in a seccomp profile installed via the operator. This can be changed by defining the list of allowed syscalls in the spod configuration as follows:
kubectl -n security-profiles-operator patch spod spod --type merge -p
'{"spec":{"allowedSyscalls": ["exit", "exit_group", "futex", "nanosleep"]}}'
From now on, the operator will only install the seccomp profiles which have only a subset of syscalls defined into the allowed list. All profiles not complying with this rule, it will be rejected.
Also every time when the list of allowed syscalls is modified in the spod configuration, the operator will automatically identify the already installed profiles which are not compliant and remove them.
You can constrain the spod scheduling via the spod configuration by setting either the tolerations or affinity.
kubectl -n security-profiles-operator patch spod spod --type merge -p
'{"spec":{"tolerations": [{...}]}}'
kubectl -n security-profiles-operator patch spod spod --type merge -p
'{"spec":{"affinity": {...}}}'
Use the SeccompProfile kind to create profiles. Example:
apiVersion: security-profiles-operator.x-k8s.io/v1beta1
kind: SeccompProfile
metadata:
namespace: my-namespace
name: profile1
spec:
defaultAction: SCMP_ACT_LOGThis seccomp profile will be saved at the path:
/var/lib/kubelet/seccomp/operator/my-namespace/profile1.json.
An init container will set up the root directory of the operator to be able to
run it without root G/UID. This will be done by creating a symlink from the
rootless profile storage /var/lib/security-profiles-operator to the default seccomp root
path inside of the kubelet root /var/lib/kubelet/seccomp/operator.
Create a pod using one of the created profiles. On Kubernetes >= 1.19, the profile can be specified as part of the pod's security context:
apiVersion: v1
kind: Pod
metadata:
name: test-pod
spec:
securityContext:
seccompProfile:
type: Localhost
localhostProfile: operator/my-namespace/profile1.json
containers:
- name: test-container
image: nginxPrior to Kubernetes 1.19, the seccomp profile is controlled by an annotation:
apiVersion: v1
kind: Pod
metadata:
name: test-pod
annotations:
seccomp.security.alpha.kubernetes.io/pod: "localhost/operator/my-namespace/profile1.json"
spec:
containers:
- name: test-container
image: nginxYou can find the profile path of the seccomp profile by checking the
seccompProfile.localhostProfile attribute:
$ kubectl --namespace my-namespace get seccompprofile profile1 --output wide
NAME STATUS AGE SECCOMPPROFILE.LOCALHOSTPROFILE
profile1 Active 14s operator/my-namespace/profile1.jsonYou can apply the profile to an existing application, such as a Deployment or DaemonSet:
kubectl --namespace my-namespace patch deployment myapp --patch '{"spec": {"template": {"spec": {"securityContext": {"seccompProfile": {"type": "Localhost", "localhostProfile": "'$(kubectl --namespace my-namespace get seccompprofile profile1 --output=jsonpath='{.status.seccompProfile\.localhostProfile}')'}}}}}}'
deployment.apps/myapp patchedThe pods in the Deployment will be automatically restarted. Check that the profile was applied correctly:
$ kubectl --namespace my-namespace get deployment myapp --output=jsonpath='{.spec.template.spec.securityContext}' | jq .
{
"seccompProfile": {
"localhostProfile": "operator/my-namespace/profile1.json",
"type": "Localhost"
}
}An example of the minimum required syscalls for a runtime such as runc (tested on version 1.0.0) to launch a container can be found in the examples. You can use this example as a starting point for creating custom profiles for your application. You can also programmatically combine it with your custom profiles in order to build application-specific profiles that only specify syscalls that are required on top of the base calls needed for the container runtime. For example:
apiVersion: security-profiles-operator.x-k8s.io/v1beta1
kind: SeccompProfile
metadata:
namespace: my-namespace
name: profile1
spec:
defaultAction: SCMP_ACT_ERRNO
baseProfileName: runc-v1.0.0
syscalls:
- action: SCMP_ACT_ALLOW
names:
- exit_groupIf you're not using runc but the alternative crun, then you can do the same by using the corresponding example profile (tested with version 0.20.1).
The next two sections describe how to bind a security profile to a container image and how to record a security profile from a running container. Both operations require the one of two SPO's webhooks to take action on the workload and in order for the webhooks to be able to reconcile the workload, the namespaces must be labeled appropriately.
The expected labels are spo.x-k8s.io/enable-binding for the binding
webhook and spo.x-k8s.io/enable-recording for the recording webhook by
default. The labels can be set with a simple kubectl label command:
$ kubectl label ns spo-test spo.x-k8s.io/enable-recording=Note that the labels' values are not important, only their presence matters. In addition, the namespace selector is configurable and the webhook configuration is described in the configuring webhooks section.
If you do not want to directly modify the SecurityContext of a Pod, for instance if you are deploying a public application, you can use the ProfileBinding resource to bind a security profile to a container's securityContext.
To bind a Pod that uses an 'nginx:1.19.1' image to the 'profile-complain' example seccomp profile, create a ProfileBinding in the same namespace as both the Pod and the SeccompProfile:
apiVersion: security-profiles-operator.x-k8s.io/v1alpha1
kind: ProfileBinding
metadata:
name: nginx-binding
spec:
profileRef:
kind: SeccompProfile
name: profile-complain
image: nginx:1.19.1If the Pod is already running, it will need to be restarted in order to pick up the profile binding. Once the binding is created and the Pod is created or recreated, the SeccompProfile should be applied to the container whose image name matches the binding:
$ kubectl get pod test-pod -o jsonpath='{.spec.containers[*].securityContext.seccompProfile}'
{"localhostProfile":"operator/default/generic/profile-complain-unsafe.json","type":"Localhost"}Binding a SELinux profile works in the same way, except you'd use the SelinuxProfile kind.
RawSelinuxProfiles are currently not supported.
The operator is capable of recording seccomp or SELinux profiles by the usage of the built-in eBPF recorder or by evaluating the audit or syslog files. Each method has its pros and cons as well as separate technical requirements.
Note that SELinux profiles can only be recorded using the log enricher.
When using the log enricher for recording seccomp or SELinux profiles, please ensure that the feature is enabled within the spod configuration resource. The log based recording works in the same way with [containerd][containerd] and [CRI-O][cri-o], while using the node local logs as input source of truth.
To record by using the enricher, create a ProfileRecording which is using
recorder: logs:
apiVersion: security-profiles-operator.x-k8s.io/v1alpha1
kind: ProfileRecording
metadata:
name: test-recording
spec:
kind: SeccompProfile
recorder: logs
podSelector:
matchLabels:
app: my-appThen we can create a workload to be recorded, for example two containers within a single pod:
apiVersion: v1
kind: Pod
metadata:
name: my-pod
labels:
app: my-app
spec:
containers:
- name: nginx
image: quay.io/security-profiles-operator/test-nginx:1.19.1
- name: redis
image: quay.io/security-profiles-operator/redis:6.2.1If the pod is up and running:
> kubectl get pods
NAME READY STATUS RESTARTS AGE
my-pod 2/2 Running 0 18s
Then the enricher should indicate that it receives audit logs for those containers:
> kubectl -n security-profiles-operator logs --since=1m --selector name=spod log-enricher
…
I0705 12:08:18.729660 1843190 enricher.go:136] log-enricher "msg"="audit" "container"="redis" "executable"="/usr/local/bin/redis-server" "namespace"="default" "node"="127.0.0.1" "pid"=1847839 "pod"="my-pod" "syscallID"=232 "syscallName"="epoll_wait" "timestamp"="1625486870.273:187492" "type"="seccomp"
Now, if we remove the pod:
> kubectl delete pod my-pod
Then the operator will reconcile two seccomp profiles:
> kubectl get sp
NAME STATUS AGE
test-recording-nginx Installed 15s
test-recording-redis Installed 15s
Recording a SELinux profile would work the same, except you'd use kind: SelinuxProfile
in the ProfileRecording object.
Please note that log based recording does not have any effect if the recorded container
is privileged, that is, the container's security context sets privileged: true. This
is because privileged containers are not subject to SELinux or seccomp policies at all
and the log based recording makes use of a special seccomp or SELinux profile respectively
to record the syscalls or SELinux events.
The operator also supports an eBPF based recorder. This
recorder only supports seccomp profiles for now. Recording via ebpf works for
kernels which expose the /sys/kernel/btf/vmlinux file per default as well as a
custom list of selected Linux kernels. In addition, this
feature requires new library versions and thus might not be enabled. You
can find out if your SPO build has the eBPF feature disabled by looking at
the build tags:
> kubectl logs --selector name=security-profiles-operator | grep buildTags
If the output contains no_bpf then the feature has been disabled.
To use the recorder, enable it by patching the spod configuration:
> kubectl -n security-profiles-operator patch spod spod --type=merge -p '{"spec":{"enableBpfRecorder":true}}'
securityprofilesoperatordaemon.security-profiles-operator.x-k8s.io/spod patched
We can verify that the recorder is up and running after the spod rollout has been finished:
> kubectl -n security-profiles-operator logs --selector name=spod -c bpf-recorder
Found 6 pods, using pod/spod-h7dpm
I1115 12:02:45.991786 110307 main.go:182] "msg"="Set logging verbosity to 0"
I1115 12:02:45.991901 110307 deleg.go:130] setup "msg"="starting component: bpf-recorder" "buildDate"="1980-01-01T00:00:00Z" "compiler"="gc" "gitCommit"="unknown" "gitTreeState"="clean" "goVersion"="go1.16.9" "libseccomp"="2.5.1" "platform"="linux/amd64" "version"="0.4.0-dev"
I1115 12:02:45.991955 110307 bpfrecorder.go:105] bpf-recorder "msg"="Setting up caches with expiry of 1h0m0s"
I1115 12:02:45.991973 110307 bpfrecorder.go:121] bpf-recorder "msg"="Starting log-enricher on node: ip-10-0-228-234.us-east-2.compute.internal"
I1115 12:02:45.994232 110307 bpfrecorder.go:152] bpf-recorder "msg"="Connecting to metrics server"
I1115 12:02:48.373469 110307 bpfrecorder.go:168] bpf-recorder "msg"="Got system mount namespace: 4026531840"
I1115 12:02:48.373518 110307 bpfrecorder.go:170] bpf-recorder "msg"="Doing BPF load/unload self-test"
I1115 12:02:48.373529 110307 bpfrecorder.go:336] bpf-recorder "msg"="Loading bpf module"
I1115 12:02:48.373570 110307 bpfrecorder.go:403] bpf-recorder "msg"="Using system btf file"
I1115 12:02:48.373770 110307 bpfrecorder.go:356] bpf-recorder "msg"="Loading bpf object from module"
I1115 12:02:48.403766 110307 bpfrecorder.go:362] bpf-recorder "msg"="Getting bpf program sys_enter"
I1115 12:02:48.403792 110307 bpfrecorder.go:368] bpf-recorder "msg"="Attaching bpf tracepoint"
I1115 12:02:48.406205 110307 bpfrecorder.go:373] bpf-recorder "msg"="Getting syscalls map"
I1115 12:02:48.406287 110307 bpfrecorder.go:379] bpf-recorder "msg"="Getting comms map"
I1115 12:02:48.406862 110307 bpfrecorder.go:396] bpf-recorder "msg"="Module successfully loaded, watching for events"
I1115 12:02:48.406908 110307 bpfrecorder.go:677] bpf-recorder "msg"="Unloading bpf module"
I1115 12:02:48.411636 110307 bpfrecorder.go:176] bpf-recorder "msg"="Starting GRPC API server"
The recorder does a system sanity check on startup to ensure everything works as
expected. This includes a load and unload of the BPF module. If this fails,
please open an issue so that we can find out what went wrong.
To record seccomp profiles by using the BPF recorder, create a
ProfileRecording which is using recorder: bpf:
apiVersion: security-profiles-operator.x-k8s.io/v1alpha1
kind: ProfileRecording
metadata:
name: my-recording
spec:
kind: SeccompProfile
recorder: bpf
podSelector:
matchLabels:
app: my-appThen we can create a workload to be recorded, for example this one:
apiVersion: v1
kind: Pod
metadata:
name: my-pod
labels:
app: my-app
spec:
containers:
- name: nginx
image: quay.io/security-profiles-operator/test-nginx:1.19.1If the pod is up and running:
> kubectl get pods
NAME READY STATUS RESTARTS AGE
my-pod 1/1 Running 0 10s
Then the BPF recorder should indicate that it found the container:
> kubectl -n security-profiles-operator logs --since=1m --selector name=spod -c log-enricher
…
I1115 12:12:30.029216 66106 bpfrecorder.go:654] bpf-recorder "msg"="Found container ID in cluster" "containerID"="c2e10af47011f6a61cd7e92073db2711796f174af35b34486967588ef7f95fbc" "containerName"="nginx"
I1115 12:12:30.029264 66106 bpfrecorder.go:539] bpf-recorder "msg"="Saving PID for profile" "mntns"=4026533352 "pid"=74384 "profile"="my-recording-nginx-1636978341"
I1115 12:12:30.029428 66106 bpfrecorder.go:512] bpf-recorder "msg"="Using short path via tracked mount namespace" "mntns"=4026533352 "pid"=74403 "profile"="my-recording-nginx-1636978341"
I1115 12:12:30.029575 66106 bpfrecorder.go:512] bpf-recorder "msg"="Using short path via tracked mount namespace" "mntns"=4026533352 "pid"=74402 "profile"="my-recording-nginx-1636978341"
…
Now, if we remove the pod:
> kubectl delete pod my-pod
Then the operator will reconcile the seccomp profile:
> kubectl get sp
NAME STATUS AGE
my-recording-nginx Installed 15s
By default, each container instance will be recorded into a separate profile. This is mostly visible when recording pods managed by a replicating controller (Deployment, DaemonSet, etc.). A realistic example might be a workload being recorded in a test environment where the recorded Deployment consists of several replicas, only one of which is receiving the test traffic. After the recording is complete, only the container that was receiving the traffic would have container all the syscalls that were actually used.
In this case, it might be useful to merge the per-container profiles
into a single profile. This can be done by setting the mergeStrategy
attribute to containers in the ProfileRecording. Note that the following
example uses a SeccompProfile as the kind but the same applies to
SelinuxProfile as well.
apiVersion: security-profiles-operator.x-k8s.io/v1alpha1
kind: ProfileRecording
metadata:
# The name of the Recording is the same as the resulting `SeccompProfile` CRD
# after reconciliation.
name: test-recording
spec:
kind: SeccompProfile
recorder: logs
mergeStrategy: containers
podSelector:
matchLabels:
app: sp-recordCreate your workload:
apiVersion: apps/v1
kind: Deployment
metadata:
name: nginx-deploy
spec:
replicas: 3
selector:
matchLabels:
app: sp-record
template:
metadata:
labels:
app: sp-record
spec:
serviceAccountName: spo-record-sa
containers:
- name: nginx-record
image: quay.io/security-profiles-operator/test-nginx-unprivileged:1.21
ports:
- containerPort: 8080You'll see that the deployment spawns three replicas. To test the merging feature, you can perform an action in one of the pods, for example:
> kubectl exec nginx-deploy-65bcbb956f-gmbrj -- bash -c "mknod /tmp/foo p"Note that this is a silly example, but shows the feature in action.
To record the individual profiles, delete the deployment:
> kubectl delete deployment nginx-deployThe profiles will be reconciled, one per container. Note that the profiles are marked as "partial" and the spod deamon instances do not reconcile the profiles.
> kubectl get sp -lspo.x-k8s.io/recording-id=test-recording --show-labels
NAME STATUS AGE LABELS
test-recording-nginx-record-gmbrj Partial 2m50s spo.x-k8s.io/container-id=sp-record,spo.x-k8s.io/partial=true,spo.x-k8s.io/profile-id=SeccompProfile-test-recording-sp-record-gmbrj,spo.x-k8s.io/recording-id=test-recording
test-recording-nginx-record-lclnb Partial 2m50s spo.x-k8s.io/container-id=sp-record,spo.x-k8s.io/partial=true,spo.x-k8s.io/profile-id=SeccompProfile-test-recording-sp-record-lclnb,spo.x-k8s.io/recording-id=test-recording
test-recording-nginx-record-wdv2r Partial 2m50s spo.x-k8s.io/container-id=sp-record,spo.x-k8s.io/partial=true,spo.x-k8s.io/profile-id=SeccompProfile-test-recording-sp-record-wdv2r,spo.x-k8s.io/recording-id=test-recordingInspecting the first partial profile, which corresponds to the pod where we ran the extra command shows that mknod is allowed:
> kubectl get sp test-recording-nginx-record-gmbrj -o yaml | grep mknod
- mknodOn the other hand the others do not:
> kubectl get sp test-recording-nginx-record-lclnb -o yaml | grep mknod
> kubectl get sp test-recording-nginx-record-wdv2r -o yaml | grep mknodTo merge the profiles, delete the profile recording to indicate that
you are finished with recording the workload. This would trigger the
merge operation done by the controller and the resulting profile will be
reconciled by the controller as seen from the Installed state:
> kubectl delete profilerecording test-recording
profilerecording.security-profiles-operator.x-k8s.io "test-recording" deleted
> kubectl get sp -lspo.x-k8s.io/recording-id=test-recording
NAME STATUS AGE
test-recording-nginx-record Installed 17mThe resulting profile will contain all the syscalls that were used by any of the containers,
including the mknod syscall:
> kubectl get sp test-recording-nginx-record -o yaml | grep mknod
- mknodThere are two kinds that can be used to define a SELinux profile - SelinuxProfile and RawSelinuxProfile.
The default one and the one created during workload recording is SelinuxProfile. It is more readable
and has several features that allow for better security hardening and better readability. The RawSelinuxProfile
kind should be used mostly when there's an already existing SELinux policy (perhaps created with udica)
that you wish to use in your cluster.
In particular, the SelinuxProfile kind:
- restricts the profiles to inherit from to the current namespace or a system-wide profile. Because there
are typically many profiles installed on the system, but only a subset should be used by cluster workloads,
the inheritable system profiles are listed in the
spodinstance inspec.selinuxOptions.allowedSystemProfiles. Depending on what distribution your nodes run, the base profile might vary, on RHEL-based systems, you might want to look at what profiles are shipped in thecontainer-selinuxRPM package. - performs basic validation of the permissions, classes and labels
- adds a new keyword
@selfthat describes the process using the policy. This allows to reuse a policy between workloads and namespaces easily, as the "usage" of the policy (see below) is based on the name and namespace.
Below is an example of a policy that can be used with a non-privileged nginx workload:
apiVersion: security-profiles-operator.x-k8s.io/v1alpha2
kind: SelinuxProfile
metadata:
name: nginx-secure
namespace: nginx-deploy
spec:
allow:
'@self':
tcp_socket:
- listen
http_cache_port_t:
tcp_socket:
- name_bind
node_t:
tcp_socket:
- node_bind
inherit:
- kind: System
name: containerAfter the policy is created, we can wait for selinuxd to install it:
$ kubectl wait --for=condition=ready selinuxprofile nginx-secure
selinuxprofile.security-profiles-operator.x-k8s.io/nginx-secure condition metThe CIL-formatted policies are placed into an emptyDir owned by the SPO where you can view
the resulting CIL policy:
$ kubectl exec -it -c selinuxd spod-fm55x -- sh
sh-4.4# cat /etc/selinux.d/nginx-secure_nginx-deploy.cil
(block nginx-secure_nginx-deploy
(blockinherit container)
(allow process nginx-secure_nginx-deploy.process ( tcp_socket ( listen )))
(allow process http_cache_port_t ( tcp_socket ( name_bind )))
(allow process node_t ( tcp_socket ( node_bind )))
)However, the binary policies are installed into the system policy store on the nodes, so you can verify that a policy has been installed:
# semodule -l | grep nginx-secureSELinux profiles are referenced to based on their "usage" string:
kubectl get selinuxprofile.security-profiles-operator.x-k8s.io/nginx-secure -nnginx-deploy -ojsonpath='{.status.usage}'
nginx-secure_nginx-deploy.process%Use this string in the workload manifest in the .spec.containers[].securityContext.seLinuxOptions attribute:
apiVersion: v1
kind: Pod
metadata:
name: nginx-secure
namespace: nginx-deploy
spec:
containers:
- image: nginxinc/nginx-unprivileged:1.21
name: nginx
securityContext:
seLinuxOptions:
# NOTE: This uses an appropriate SELinux type
type: nginx-secure_nginx-deploy.processNote that the SELinux type must exist before creating the workload.
Please refer to the seccomp recording documentation, recording a SELinux
profile would work the same, except you'd use kind: SelinuxProfile. Note
that only the log enricher is capable of recording SELinux profiles.
The security-profiles-operator can optionally be run to watch SeccompProfiles in
a single namespace. This is advantageous because it allows for tightening the
RBAC permissions required by the operator's ServiceAccount. To modify the
operator deployment to run in a single namespace, use the
namespace-operator.yaml manifest with your namespace of choice:
NAMESPACE=<your-namespace>
curl https://raw.githubusercontent.com/kubernetes-sigs/security-profiles-operator/main/deploy/namespace-operator.yaml | sed "s/NS_REPLACE/$NAMESPACE/g" | kubectl apply -f -Since restricting the operator to a single namespace amounts to setting the RESTRICT_TO_NAMESPACE
environment variable, the easiest way to set that (or any other variable for SPO) is by editing the
Subscription object and setting the spec.config.env field:
spec:
config:
env:
- name: RESTRICT_TO_NAMESPACE
value: <your-namespace>OLM would then take care of updating the operator Deployment object with the new environment variable.
Please refer to the OLM documentation
for more details on tuning the operator's configuration with the Subscription objects.
The security-profiles-operator provides two metrics endpoints, which are secured
by a kube-rbac-proxy sidecar
container. All metrics are exposd via the metrics service within the
security-profiles-operator namespace:
> kubectl get svc/metrics -n security-profiles-operator
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
metrics ClusterIP 10.0.0.228 <none> 443/TCP 43s
The operator ships a cluster role and corresponding binding spo-metrics-client
to retrieve the metrics from within the cluster. There are two metrics paths
available:
metrics.security-profiles-operator/metrics: for controller runtime metricsmetrics.security-profiles-operator/metrics-spod: for the operator daemon metrics
To retrieve the metrics, just query the service endpoint by using the default
serviceaccount token in the security-profiles-operator namespace:
> kubectl run --rm -i --restart=Never --image=registry.fedoraproject.org/fedora-minimal:latest \
-n security-profiles-operator metrics-test -- bash -c \
'curl -ks -H "Authorization: Bearer $(cat /var/run/secrets/kubernetes.io/serviceaccount/token)" https://metrics.security-profiles-operator/metrics-spod'
…
# HELP security_profiles_operator_seccomp_profile_total Counter about seccomp profile operations.
# TYPE security_profiles_operator_seccomp_profile_total counter
security_profiles_operator_seccomp_profile_total{operation="delete"} 1
security_profiles_operator_seccomp_profile_total{operation="update"} 2
…
If the metrics have to be retrieved from a different namespace, just link the
service account to the spo-metrics-client ClusterRoleBinding or create a new
one:
> kubectl get clusterrolebinding spo-metrics-client -o wide
NAME ROLE AGE USERS GROUPS SERVICEACCOUNTS
spo-metrics-client ClusterRole/spo-metrics-client 35m security-profiles-operator/default
Every metrics server pod from the DaemonSet runs with the same set of certificates
(secret metrics-server-cert: tls.crt and tls.key) in the
security-profiles-operator namespace. This means a pod like this can be used
to omit the --insecure/-k flag:
---
apiVersion: v1
kind: Pod
metadata:
name: test-pod
spec:
containers:
- name: test-container
image: registry.fedoraproject.org/fedora-minimal:latest
command:
- bash
- -c
- |
curl -s --cacert /var/run/secrets/metrics/ca.crt \
-H "Authorization: Bearer $(cat /var/run/secrets/kubernetes.io/serviceaccount/token)" \
https://metrics.security-profiles-operator/metrics-spod
volumeMounts:
- mountPath: /var/run/secrets/metrics
name: metrics-cert-volume
readOnly: true
restartPolicy: Never
volumes:
- name: metrics-cert-volume
secret:
defaultMode: 420
secretName: metrics-server-certThe controller-runtime (/metrics) as well as the DaemonSet endpoint
(/metrics-spod) already provide a set of default metrics. Beside that, those
additional metrics are provided by the daemon, which are always prefixed with
security_profiles_operator_:
| Metric Key | Possible Labels | Type | Purpose |
|---|---|---|---|
seccomp_profile_total |
operation={delete,update} |
Counter | Amount of seccomp profile operations. |
seccomp_profile_audit_total |
node, namespace, pod, container, executable, syscall |
Counter | Amount of seccomp profile audit operations. Requires the log-enricher to be enabled. |
seccomp_profile_bpf_total |
node, mount_namespace, profile |
Counter | Amount of seccomp profile bpf operations. Requires the bpf-recorder to be enabled. |
seccomp_profile_error_total |
reason={SeccompNotSupportedOnNode,InvalidSeccompProfile,CannotSaveSeccompProfile,CannotRemoveSeccompProfile,CannotUpdateSeccompProfile,CannotUpdateNodeStatus} |
Counter | Amount of seccomp profile errors. |
selinux_profile_total |
operation={delete,update} |
Counter | Amount of selinux profile operations. |
selinux_profile_audit_total |
node, namespace, pod, container, executable, scontext,tcontext |
Counter | Amount of selinux profile audit operations. Requires the log-enricher to be enabled. |
selinux_profile_error_total |
reason={CannotSaveSelinuxPolicy,CannotUpdatePolicyStatus,CannotRemoveSelinuxPolicy,CannotContactSelinuxd,CannotWritePolicyFile,CannotGetPolicyStatus} |
Counter | Amount of selinux profile errors. |
If the Kubernetes cluster has the Prometheus
Operator deployed,
then the Security Profiles Operator will automatically create a ServiceMonitor
resource within its namespace. This monitor allows automatic metrics discovery
within the cluster, which is pointing to the right service, TLS certificates as
well as bearer token secret.
When running on OpenShift, then the only configuration to be done is enabling user workloads by applying the following config map:
apiVersion: v1
kind: ConfigMap
metadata:
name: cluster-monitoring-config
namespace: openshift-monitoring
data:
config.yaml: |
enableUserWorkload: trueAfter that, the Security Profiles Operator can be deployed or updated, which
will reconcile the ServiceMonitor into the cluster:
> kubectl -n security-profiles-operator logs security-profiles-operator-d7c8cfc86-47qh2 | grep monitor
I0520 09:29:35.578165 1 spod_controller.go:282] spod-config "msg"="Deploying operator service monitor"
> kubectl -n security-profiles-operator get servicemonitor
NAME AGE
security-profiles-operator-monitor 35m
We can now verify in the Prometheus targets that all endpoints are serving the metrics:
> kubectl port-forward -n openshift-user-workload-monitoring pod/prometheus-user-workload-0 9090
Forwarding from 127.0.0.1:9090 -> 9090
Forwarding from [::1]:9090 -> 9090
The OpenShift UI is now able to display the operator metrics, too:
The operator ships with a log enrichment feature, which is disabled per
default. The reason for that is that the log enricher container runs in
privileged mode to be able to read the audit logs from the local node. It is also
required that the enricher is able to read the host processes and therefore runs
within host PID namespace (hostPID).
One of the following requirements to the Kubernetes node have to be fulfilled to use the log enrichment feature:
- auditd needs to run and has to be configured to log into
/var/log/audit/audit.log - syslog can be used as fallback to auditd and needs to log into
/var/log/syslog. Depending on the system configuration, a printk rate limiting may be in place which has direct influence on the log enrichment. To diable the rate limiting, set the following sysctls:> sysctl -w kernel.printk_ratelimit=0 > sysctl -w kernel.printk_ratelimit_burst=0
If all requirements are met, then the feature can be enabled by patching the
spod configuration:
> kubectl -n security-profiles-operator patch spod spod --type=merge -p '{"spec":{"enableLogEnricher":true}}'
securityprofilesoperatordaemon.security-profiles-operator.x-k8s.io/spod patched
Alternatively, make sure the operator deployment sets the ENABLE_LOG_ENRICHER variable,
to true, either by setting the environment variable in the deployment or by enabling
the variable trough a Subscription resource, when installing the operator using OLM
(see Restricting the operator to specific nodes
for an example of setting another variable).
Now the operator will take care of re-deploying the spod DaemonSet and the
enricher should listening on new changes to the audit logs:
> kubectl -n security-profiles-operator logs -f ds/spod log-enricher
I0623 12:51:04.257814 1854764 deleg.go:130] setup "msg"="starting component: log-enricher" "buildDate"="1980-01-01T00:00:00Z" "compiler"="gc" "gitCommit"="unknown" "gitTreeState"="clean" "goVersion"="go1.16.2" "platform"="linux/amd64" "version"="0.4.0-dev"
I0623 12:51:04.257890 1854764 enricher.go:44] log-enricher "msg"="Starting log-enricher on node: 127.0.0.1"
I0623 12:51:04.257898 1854764 enricher.go:46] log-enricher "msg"="Connecting to local GRPC server"
I0623 12:51:04.258061 1854764 enricher.go:69] log-enricher "msg"="Reading from file /var/log/audit/audit.log"
2021/06/23 12:51:04 Seeked /var/log/audit/audit.log - &{Offset:0 Whence:2}
To be able to trace an application, we have to create a logging profile like this:
apiVersion: security-profiles-operator.x-k8s.io/v1beta1
kind: SeccompProfile
metadata:
name: log
namespace: default
spec:
defaultAction: SCMP_ACT_LOGAfter the profile has been created, a corresponding workload can be started to use the profile:
apiVersion: v1
kind: Pod
metadata:
name: log-pod
spec:
securityContext:
seccompProfile:
type: Localhost
localhostProfile: operator/default/log.json
containers:
- name: log-container
image: nginxIf the pod is running, then we can examine the log enricher output:
> kubectl -n security-profiles-operator logs -f ds/spod log-enricher
…
I0623 12:59:10.220291 1854764 container.go:77] log-enricher "msg"="container ID is still empty, retrying" "containerName"="log-container"
I0623 12:59:10.724938 1854764 container.go:77] log-enricher "msg"="container ID is still empty, retrying" "containerName"="log-container"
I0623 12:59:11.479869 1854764 enricher.go:111] log-enricher "msg"="audit" "container"="log-container" "executable"="/" "namespace"="default" "node"="127.0.0.1" "pid"=1905792 "pod"="log-pod" "syscallID"=3 "syscallName"="close" "timestamp"="1624453150.205:1061" "type"="seccomp"
I0623 12:59:11.487323 1854764 enricher.go:111] log-enricher "msg"="audit" "container"="log-container" "executable"="/" "namespace"="default" "node"="127.0.0.1" "pid"=1905792 "pod"="log-pod" "syscallID"=157 "syscallName"="prctl" "timestamp"="1624453150.205:1062" "type"="seccomp"
I0623 12:59:11.492157 1854764 enricher.go:111] log-enricher "msg"="audit" "container"="log-container" "executable"="/" "namespace"="default" "node"="127.0.0.1" "pid"=1905792 "pod"="log-pod" "syscallID"=157 "syscallName"="prctl" "timestamp"="1624453150.205:1063" "type"="seccomp"
…
I0623 12:59:20.258523 1854764 enricher.go:111] log-enricher "msg"="audit" "container"="log-container" "executable"="/usr/sbin/nginx" "namespace"="default" "node"="127.0.0.1" "pid"=1905792 "pod"="log-pod" "syscallID"=12 "syscallName"="brk" "timestamp"="1624453150.235:2873" "type"="seccomp"
I0623 12:59:20.263349 1854764 enricher.go:111] log-enricher "msg"="audit" "container"="log-container" "executable"="/usr/sbin/nginx" "namespace"="default" "node"="127.0.0.1" "pid"=1905792 "pod"="log-pod" "syscallID"=21 "syscallName"="access" "timestamp"="1624453150.235:2874" "type"="seccomp"
I0623 12:59:20.354091 1854764 enricher.go:111] log-enricher "msg"="audit" "container"="log-container" "executable"="/usr/sbin/nginx" "namespace"="default" "node"="127.0.0.1" "pid"=1905792 "pod"="log-pod" "syscallID"=257 "syscallName"="openat" "timestamp"="1624453150.235:2875" "type"="seccomp"
I0623 12:59:20.358844 1854764 enricher.go:111] log-enricher "msg"="audit" "container"="log-container" "executable"="/usr/sbin/nginx" "namespace"="default" "node"="127.0.0.1" "pid"=1905792 "pod"="log-pod" "syscallID"=5 "syscallName"="fstat" "timestamp"="1624453150.235:2876" "type"="seccomp"
I0623 12:59:20.363510 1854764 enricher.go:111] log-enricher "msg"="audit" "container"="log-container" "executable"="/usr/sbin/nginx" "namespace"="default" "node"="127.0.0.1" "pid"=1905792 "pod"="log-pod" "syscallID"=9 "syscallName"="mmap" "timestamp"="1624453150.235:2877" "type"="seccomp"
I0623 12:59:20.454127 1854764 enricher.go:111] log-enricher "msg"="audit" "container"="log-container" "executable"="/usr/sbin/nginx" "namespace"="default" "node"="127.0.0.1" "pid"=1905792 "pod"="log-pod" "syscallID"=3 "syscallName"="close" "timestamp"="1624453150.235:2878" "type"="seccomp"
I0623 12:59:20.458654 1854764 enricher.go:111] log-enricher "msg"="audit" "container"="log-container" "executable"="/usr/sbin/nginx" "namespace"="default" "node"="127.0.0.1" "pid"=1905792 "pod"="log-pod" "syscallID"=257 "syscallName"="openat" "timestamp"="1624453150.235:2879" "type"="seccomp"
…
The startup of the nginx container already invokes a huge amount of syscalls, which are now all available within a human readable way within the log enricher.
The metrics endpoint of the Security Profiles Operator can be used to examine
the log enricher data in a more structured way. This means that each syscall
invocation will create a new metric entry
security_profiles_operator_seccomp_profile_audit_total containing the
corresponding metadata as labels:
# HELP security_profiles_operator_seccomp_profile_audit_total Counter about seccomp profile audits, requires the log enricher to be enabled.
# TYPE security_profiles_operator_seccomp_profile_audit_total counter
security_profiles_operator_seccomp_profile_audit_total{container="log-container",executable="/usr/sbin/nginx",namespace="default",node="127.0.0.1",pod="log-pod",syscall="access"} 1
security_profiles_operator_seccomp_profile_audit_total{container="log-container",executable="/usr/sbin/nginx",namespace="default",node="127.0.0.1",pod="log-pod",syscall="arch_prctl"} 1
security_profiles_operator_seccomp_profile_audit_total{container="log-container",executable="/usr/sbin/nginx",namespace="default",node="127.0.0.1",pod="log-pod",syscall="bind"} 2
security_profiles_operator_seccomp_profile_audit_total{container="log-container",executable="/usr/sbin/nginx",namespace="default",node="127.0.0.1",pod="log-pod",syscall="brk"} 18
security_profiles_operator_seccomp_profile_audit_total{container="log-container",executable="/usr/sbin/nginx",namespace="default",node="127.0.0.1",pod="log-pod",syscall="close"} 154
security_profiles_operator_seccomp_profile_audit_total{container="log-container",executable="/usr/sbin/nginx",namespace="default",node="127.0.0.1",pod="log-pod",syscall="pread64"} 4
security_profiles_operator_seccomp_profile_audit_total{container="log-container",executable="/usr/sbin/nginx",namespace="default",node="127.0.0.1",pod="log-pod",syscall="prlimit64"} 3
security_profiles_operator_seccomp_profile_audit_total{container="log-container",executable="/usr/sbin/nginx",namespace="default",node="127.0.0.1",pod="log-pod",syscall="pwrite64"} 1
security_profiles_operator_seccomp_profile_audit_total{container="log-container",executable="/usr/sbin/nginx",namespace="default",node="127.0.0.1",pod="log-pod",syscall="recvmsg"} 120
security_profiles_operator_seccomp_profile_audit_total{container="log-container",executable="/usr/sbin/nginx",namespace="default",node="127.0.0.1",pod="log-pod",syscall="rt_sigaction"} 14
security_profiles_operator_seccomp_profile_audit_total{container="log-container",executable="/usr/sbin/nginx",namespace="default",node="127.0.0.1",pod="log-pod",syscall="rt_sigprocmask"} 14
security_profiles_operator_seccomp_profile_audit_total{container="log-container",executable="/usr/sbin/nginx",namespace="default",node="127.0.0.1",pod="log-pod",syscall="rt_sigsuspend"} 1
security_profiles_operator_seccomp_profile_audit_total{container="log-container",executable="/usr/sbin/nginx",namespace="default",node="127.0.0.1",pod="log-pod",syscall="sendmsg"} 68
security_profiles_operator_seccomp_profile_audit_total{container="log-container",executable="/usr/sbin/nginx",namespace="default",node="127.0.0.1",pod="log-pod",syscall="set_robust_list"} 13
security_profiles_operator_seccomp_profile_audit_total{container="log-container",executable="/usr/sbin/nginx",namespace="default",node="127.0.0.1",pod="log-pod",syscall="set_tid_address"} 1
security_profiles_operator_seccomp_profile_audit_total{container="log-container",executable="/usr/sbin/nginx",namespace="default",node="127.0.0.1",pod="log-pod",syscall="setgid"} 12
security_profiles_operator_seccomp_profile_audit_total{container="log-container",executable="/usr/sbin/nginx",namespace="default",node="127.0.0.1",pod="log-pod",syscall="setgroups"} 12
security_profiles_operator_seccomp_profile_audit_total{container="log-container",executable="/usr/sbin/nginx",namespace="default",node="127.0.0.1",pod="log-pod",syscall="setsockopt"} 3
security_profiles_operator_seccomp_profile_audit_total{container="log-container",executable="/usr/sbin/nginx",namespace="default",node="127.0.0.1",pod="log-pod",syscall="setuid"} 12
security_profiles_operator_seccomp_profile_audit_total{container="log-container",executable="/usr/sbin/nginx",namespace="default",node="127.0.0.1",pod="log-pod",syscall="socket"} 6
security_profiles_operator_seccomp_profile_audit_total{container="log-container",executable="/usr/sbin/nginx",namespace="default",node="127.0.0.1",pod="log-pod",syscall="socketpair"} 24
security_profiles_operator_seccomp_profile_audit_total{container="log-container",executable="/usr/sbin/nginx",namespace="default",node="127.0.0.1",pod="log-pod",syscall="stat"} 6
security_profiles_operator_seccomp_profile_audit_total{container="log-container",executable="/usr/sbin/nginx",namespace="default",node="127.0.0.1",pod="log-pod",syscall="sysinfo"} 1
security_profiles_operator_seccomp_profile_audit_total{container="log-container",executable="/usr/sbin/nginx",namespace="default",node="127.0.0.1",pod="log-pod",syscall="uname"} 2
security_profiles_operator_seccomp_profile_audit_total{container="log-container",executable="/usr/sbin/nginx",namespace="default",node="127.0.0.1",pod="log-pod",syscall="write"} 20
Both profile binding and profile recording make use of webhooks. Their configuration (an instance of
MutatingWebhookConfiguration CR) is managed by SPO itself and not part of the deployed YAML manifests.
While the defaults should be acceptable for the majority of users and the webhooks do nothing unless an
instance of either ProfileBinding or ProfileRecording exists in a namespace and in addition the
namespace must be labeled with either spo.x-k8s.io/enable-binding or spo.x-k8s.io/enable-recording
respectively by default, it might still be useful to configure the webhooks.
In order to change webhook's configuration, the spod CR exposes an object
webhookOptions that allows the failurePolicy, namespaceSelector
and objectSelector to be set. This way you can set the webhooks to
"soft-fail" or restrict them to a subset of a namespaces and inside those namespaces
select only a subset of object matching the objectSelector so that even
if the webhooks had a bug that would prevent them from running at all,
other namespaces or resources wouldn't be affected.
For example, to set the binding.spo.io webhook's configuration to ignore errors as well as restrict it
to a subset of namespaces labeled with spo.x-k8s.io/bind-here=true, create a following patch file:
spec:
webhookOptions:
- name: binding.spo.io
failurePolicy: Ignore
namespaceSelector:
matchExpressions:
- key: spo.x-k8s.io/bind-here
operator: In
values:
- "true"And patch the spod/spod instance:
$ kubectl -nsecurity-profiles-operator patch spod spod -p $(cat /tmp/spod-wh.patch) --type=mergeTo view the resulting MutatingWebhookConfiguration, call:
$ kubectl -nsecurity-profiles-operator get MutatingWebhookConfiguration spo-mutating-webhook-configuration -oyamlConfirm that the profile is being reconciled:
$ kubectl -n security-profiles-operator logs security-profiles-operator-mzw9t
I1019 19:34:14.942464 1 main.go:90] setup "msg"="starting security-profiles-operator" "buildDate"="2020-10-19T19:31:24Z" "compiler"="gc" "gitCommit"="a3ef0e1ea6405092268c18f240b62015c247dd9d" "gitTreeState"="dirty" "goVersion"="go1.15.1" "platform"="linux/amd64" "version"="0.2.0-dev"
I1019 19:34:15.348389 1 listener.go:44] controller-runtime/metrics "msg"="metrics server is starting to listen" "addr"=":8080"
I1019 19:34:15.349076 1 main.go:126] setup "msg"="starting manager"
I1019 19:34:15.349449 1 internal.go:391] controller-runtime/manager "msg"="starting metrics server" "path"="/metrics"
I1019 19:34:15.350201 1 controller.go:142] controller "msg"="Starting EventSource" "controller"="profile" "reconcilerGroup"="security-profiles-operator.x-k8s.io" "reconcilerKind"="SeccompProfile" "source"={"Type":{"metadata":{"creationTimestamp":null},"spec":{"defaultAction":""}}}
I1019 19:34:15.450674 1 controller.go:149] controller "msg"="Starting Controller" "controller"="profile" "reconcilerGroup"="security-profiles-operator.x-k8s.io" "reconcilerKind"="SeccompProfile"
I1019 19:34:15.450757 1 controller.go:176] controller "msg"="Starting workers" "controller"="profile" "reconcilerGroup"="security-profiles-operator.x-k8s.io" "reconcilerKind"="SeccompProfile" "worker count"=1
I1019 19:34:15.453102 1 profile.go:148] profile "msg"="Reconciled profile from SeccompProfile" "namespace"="security-profiles-operator" "profile"="nginx-1.19.1" "name"="nginx-1.19.1" "resource version"="728"
I1019 19:34:15.453618 1 profile.go:148] profile "msg"="Reconciled profile from SeccompProfile" "namespace"="security-profiles-operator" "profile"="security-profiles-operator" "name"="security-profiles-operator" "resource version"="729"Confirm that the seccomp profiles are saved into the correct path:
$ kubectl exec -t -n security-profiles-operator security-profiles-operator-v6p2h -- ls /var/lib/kubelet/seccomp/operator/my-namespace/my-workload
profile-block.json
profile-complain.jsonPlease note corrupted seccomp profiles can disrupt your workloads. Therefore, ensure that the user used cannot be abused by:
- Not creating that user on the actual node.
- Restricting the user ID to only security-profiles-operator (i.e. using PSP).
- Not allowing other workloads to map any part of the path
/var/lib/kubelet/seccomp/operator.
It is possible to enable the CPU and memory profiling endpoints for debugging
purposes. To be able to utilize the profiling support, patch the spod config by
adjusting the enableProfiling value:
> kubectl -n security-profiles-operator patch spod spod --type=merge -p '{"spec":{"enableProfiling":true}}'
securityprofilesoperatordaemon.security-profiles-operator.x-k8s.io/spod patched
The containers of the daemon should now indicate that it's serving the profiling endpoint, where every container is using a different port:
> k logs --selector name=spod -c security-profiles-operator | grep "Starting profiling"
I1202 15:14:40.276363 2185724 main.go:226] "msg"="Starting profiling server" "endpoint"="localhost:6060"
> k logs --selector name=spod -c log-enricher | grep "Starting profiling"
I1202 15:14:40.364046 2185814 main.go:226] "msg"="Starting profiling server" "endpoint"="localhost:6061"
> k logs --selector name=spod -c bpf-recorder | grep "Starting profiling"
I1202 15:14:40.457506 2185914 main.go:226] "msg"="Starting profiling server" "endpoint"="localhost:6062"
Then use the pprof tool to look at the heap profile:
> go tool pprof http://$PODIP:6060/debug/pprof/heap
Or to look at a 30-second CPU profile:
go tool pprof http://$PODIP:6060/debug/pprof/profile?seconds=30
Note that selinuxd, if enabled, doesn't set up a HTTP listener, but only
listens on a UNIX socket shared between selinuxd and the spod DS pod.
Nonetheless, this socket can be used to reach the profiling enpoint as
well:
kubectl exec spod-4pt84 -c selinuxd -- curl --unix-socket /var/run/selinuxd/selinuxd.sock http://localhost/debug/pprof/heap --output - > /tmp/heap.selinuxd
go tool pprof /tmp/heap.selinuxd
For a study of the facility in action, please visit: https://blog.golang.org/2011/06/profiling-go-programs.html
The operator configuration supports specifying a custom /proc location, which
is required for the container ID retrieval of the log-enricher as well as the
bpf-recorder. To use a custom path for /proc, just patch the spod accordingly:
kubectl patch spod spod --type=merge -p '{"spec":{"hostProcVolumePath":"/my-proc"}}'
There are several things particular to OpenShift that are useful to be aware of when deploying and recording security profiles, mostly coming from OpenShift's default use of SCCs.
Recording of SELinux policies is implemented with a webhook that injects a special SELinux
type to the pods being recorded. This type makes the pod run in "permissive" mode, logging
all the AVC denials into audit.log. By default, especially with the more restrictive SCCs,
a workload is not allowed to run with a custom SELinux policy, but uses an autogenerated type.
Therefore in order to record a workload, the workload must use a service account that is allowed
to use an SCC that allows the webhook to inject this permissive type into it. This can be achieved
by using any SCC that uses seLinuxContext: RunAsAny, including the privileged SCC shipped
by default with OpenShift.
When deploying security policies (both SELinux and seccomp) for replicating controllers (deployments,
daemonsets, ...), note that the pods that these controllers spawn are not running with the identity
of the user who creates the workload. Unless a ServiceAccount is selected, this means that the pods
might fall back to using one of the secure but restricted SCCs which don't allow to use a custom security
policy.
One option is to use an SCC with seLinuxContext: RunAsAny and/or seccompProfiles: [*], but it's
more secure to only restrict your workloads to the security profiles they should be using.
Taking the SELinux policy we recorded earlier for an nginx deployment as an
example, we might create the following SCC which is based on the restricted
SCC shipped in OpenShift, just allows our SELinux policy to be used.
Note that we'll be deploying in the nginx-secure namespace, as you can
see from the ServiceAccount name we are putting into the users array.
apiVersion: security.openshift.io/v1
kind: SecurityContextConstraints
metadata:
annotations:
kubernetes.io/description: A special SCC for running nginx with a custom SELinux policy
name: nginx-secure
allowHostIPC: false
allowHostNetwork: false
allowHostPID: false
allowHostPorts: false
allowPrivilegeEscalation: true
allowPrivilegedContainer: false
allowedCapabilities: null
defaultAddCapabilities: null
fsGroup:
type: MustRunAs
priority: null
readOnlyRootFilesystem: false
requiredDropCapabilities:
- KILL
- MKNOD
- SETUID
- SETGID
runAsUser:
type: MustRunAsRange
seLinuxContext:
type: MustRunAs
seLinuxOptions:
type: test-selinux-recording-nginx-0_nginx-secure.process
supplementalGroups:
type: RunAsAny
users:
- system:serviceaccount:nginx-secure:nginx-sa
volumes:
- configMap
- downwardAPI
- emptyDir
- persistentVolumeClaim
- projected
- secretPlease note that a common mistake when creating custom SCCs is to bind them to a wide range of users or SAs
through the group attribute, e.g. the system:authenticated group. Make sure your SCC is only usable by
the serviceAccount it is supposed to be used by. Please refer to the OCP documentation
or this Red Hat blog post for more information
on managing SCCs.
Then we create the appropriate role:
apiVersion: rbac.authorization.k8s.io/v1
kind: Role
metadata:
name: nginx
namespace: nginx-secure
rules:
- apiGroups:
- security.openshift.io
resources:
- securitycontextconstraints
resourceNames:
- nginx-secure
verbs:
- useand finally a role binding and the SA.
With all that set up, we can finally create our deployment:
apiVersion: apps/v1
kind: Deployment
metadata:
name: my-deployment
spec:
selector:
matchLabels:
app: nginx
replicas: 2
template:
metadata:
labels:
app: nginx
spec:
serviceAccountName: nginx-sa
containers:
- name: nginx
image: nginxinc/nginx-unprivileged:1.21Note that we don't specify the SELinux type at all in the workload, that's handled by the SCC instead.
When the pods are created through the deployment and its ReplicaSet, they should be
running with the appropriate profile.
To uninstall, remove the profiles before removing the rest of the operator:
$ kubectl delete seccompprofiles --all --all-namespaces
$ kubectl delete -f https://raw.githubusercontent.com/kubernetes-sigs/security-profiles-operator/main/deploy/operator.yaml