change workflow to allow actionner to also delete standalone pods (#459)

+ refactor GetOwnerKind method

actionners/kubernetes/drain/drain.go

@@ -220,13 +220,7 @@ func (a Actionner) RunWithClient(client k8s.DrainClient, event *events.Event, ac
 		go func(pod corev1.Pod) {
 			defer wg.Done()
 
-			ownerKind, err := k8s.GetOwnerKind(p)
-			if err != nil {
-				utils.PrintLog("warning", utils.LogLine{Message: fmt.Sprintf("error getting pod '%v' owner kind: %v", p.Name, err)})
-				atomic.AddInt32(&otherErrorsCount, 1)
-				return
-			}
-
+			ownerKind := k8s.PodKind(p)
 			switch ownerKind {
 			case utils.DaemonSetStr:
 				if parameters.IgnoreDaemonsets {

actionners/kubernetes/terminate/terminate.go

@@ -50,6 +50,7 @@ rules:
     grace_period_seconds: 5
     ignore_daemonsets: true
     ignore_statefulsets: true
+	ignore_standalone_pods: true
     min_healthy_replicas: 33%
 `
 )
@@ -59,10 +60,11 @@ var (
 )
 
 type Parameters struct {
-	MinHealthyReplicas string `mapstructure:"min_healthy_replicas" validate:"omitempty,is_absolut_or_percent"`
-	IgnoreDaemonsets   bool   `mapstructure:"ignore_daemonsets" validate:"omitempty"`
-	IgnoreStatefulSets bool   `mapstructure:"ignore_statefulsets" validate:"omitempty"`
-	GracePeriodSeconds int    `mapstructure:"grace_period_seconds" validate:"omitempty"`
+	MinHealthyReplicas   string `mapstructure:"min_healthy_replicas" validate:"omitempty,is_absolut_or_percent"`
+	IgnoreDaemonsets     bool   `mapstructure:"ignore_daemonsets" validate:"omitempty"`
+	IgnoreStatefulSets   bool   `mapstructure:"ignore_statefulsets" validate:"omitempty"`
+	IgnoreStandalonePods bool   `mapstructure:"ignore_standalone_pods" validate:"omitempty"`
+	GracePeriodSeconds   int    `mapstructure:"grace_period_seconds" validate:"omitempty"`
 }
 
 type Actionner struct{}
@@ -92,10 +94,11 @@ func (a Actionner) Information() models.Information {
 }
 func (a Actionner) Parameters() models.Parameters {
 	return Parameters{
-		MinHealthyReplicas: "",
-		IgnoreDaemonsets:   false,
-		IgnoreStatefulSets: false,
-		GracePeriodSeconds: 0,
+		MinHealthyReplicas:   "",
+		IgnoreDaemonsets:     false,
+		IgnoreStatefulSets:   false,
+		IgnoreStandalonePods: true,
+		GracePeriodSeconds:   0,
 	}
 }
 
@@ -137,16 +140,7 @@ func (a Actionner) Run(event *events.Event, action *rules.Action) (utils.LogLine
 			err
 	}
 
-	ownerKind, err := k8s.GetOwnerKind(*pod)
-	if err != nil {
-		return utils.LogLine{
-				Objects: objects,
-				Error:   err.Error(),
-				Status:  utils.FailureStr,
-			},
-			nil,
-			err
-	}
+	ownerKind := k8s.PodKind(*pod)
 
 	switch ownerKind {
 	case utils.DaemonSetStr:
@@ -226,6 +220,14 @@ func (a Actionner) Run(event *events.Event, action *rules.Action) (utils.LogLine
 				}
 			}
 		}
+	case utils.StandalonePodStr:
+		if parameters.IgnoreStandalonePods {
+			return utils.LogLine{
+				Objects: objects,
+				Status:  "ignored",
+				Result:  fmt.Sprintf("the pod '%v' in the namespace '%v' is a standalone pod and will be ignored.", podName, namespace),
+			}, nil, nil
+		}
 	}
 
 	err = client.Clientset.CoreV1().Pods(namespace).Delete(context.Background(), podName, metav1.DeleteOptions{GracePeriodSeconds: gracePeriodSeconds})

internal/kubernetes/client/client.go

@@ -541,11 +541,13 @@ func (client Client) EvictPod(pod corev1.Pod) error {
 	return nil
 }
 
-func GetOwnerKind(pod corev1.Pod) (string, error) {
+// PodKind returns the type of the pod
+// if no owner reference is found, the pod is considered as a standalone pod
+func PodKind(pod corev1.Pod) string {
 	if len(pod.OwnerReferences) == 0 {
-		return "", fmt.Errorf("no owner reference found")
+		return utils.StandalonePodStr
 	}
-	return pod.OwnerReferences[0].Kind, nil
+	return pod.OwnerReferences[0].Kind
 }
 
 func GetOwnerName(pod corev1.Pod) (string, error) {

rules.yaml

@@ -1,5 +1,8 @@
 - action: Terminate Pod
   actionner: kubernetes:terminate
+  parameters:
+    grace_period_seconds: 5
+    ignore_standalone_pods: true
 
 - action: Disable outbound connections
   actionner: kubernetes:networkpolicy
@@ -50,7 +53,7 @@
     output_fields:
       - k8s.ns.name!=kube-system, k8s.ns.name!=falco
   actions:
-    - action: Label Pod as Suspicious
+    - action: Terminate Pod
 
 - rule: Test invoke lambda
   match:

utils/utils.go

@@ -42,9 +42,10 @@ const (
 
 	ansiChars string = "[\u001B\u009B][[\\]()#;?]*(?:(?:(?:[a-zA-Z\\d]*(?:;[a-zA-Z\\d]*)*)?\u0007)|(?:(?:\\d{1,4}(?:;\\d{0,4})*)?[\\dA-PRZcf-ntqry=><~]))"
 
-	DaemonSetStr   = "DaemonSet"
-	StatefulSetStr = "StatefulSet"
-	ReplicaSetStr  = "ReplicaSet"
+	DaemonSetStr     = "DaemonSet"
+	StatefulSetStr   = "StatefulSet"
+	ReplicaSetStr    = "ReplicaSet"
+	StandalonePodStr = "StandalonePod"
 )
 
 type LogLine struct {