[host-sensor] first integration in kubescape

hostsensorutils/hostsensorgetfrompod.go

@@ -0,0 +1,107 @@
+package hostsensorutils
+
+import (
+	"encoding/json"
+	"fmt"
+	"sync"
+
+	"k8s.io/apimachinery/pkg/runtime/schema"
+	"sigs.k8s.io/yaml"
+)
+
+type HostSensorDataEnvelope struct {
+	schema.GroupVersionKind
+	NodeName string          `json:"nodeName"`
+	Data     json.RawMessage `json:"data"`
+}
+
+func (hsh *HostSensorHandler) getPodList() (res map[string]string, err error) {
+	hsh.podListLock.RLock()
+	jsonBytes, err := json.Marshal(hsh.HostSensorPodNames)
+	hsh.podListLock.RUnlock()
+	if err != nil {
+		return res, fmt.Errorf("failed to marshal pod list: %v", err)
+	}
+	err = json.Unmarshal(jsonBytes, &res)
+	if err != nil {
+		return res, fmt.Errorf("failed to unmarshal pod list: %v", err)
+	}
+	return res, nil
+}
+
+func (hsh *HostSensorHandler) HTTPGetToPod(podName, path string) ([]byte, error) {
+	//  send the request to the port
+
+	restProxy := hsh.k8sObj.KubernetesClient.CoreV1().Pods(hsh.DaemonSet.Namespace).ProxyGet("http", podName, fmt.Sprintf("%d", hsh.HostSensorPort), path, map[string]string{})
+	return restProxy.DoRaw(hsh.k8sObj.Context)
+
+}
+
+func (hsh *HostSensorHandler) ForwardToPod(podName, path string) ([]byte, error) {
+	// NOT IN USE:
+	// ---
+	// spawn port forwarding
+	// req := hsh.k8sObj.KubernetesClient.CoreV1().RESTClient().Post()
+	// req = req.Name(podName)
+	// req = req.Namespace(hsh.DaemonSet.Namespace)
+	// req = req.Resource("pods")
+	// req = req.SubResource("portforward")
+	// ----
+	// https://github.com/gianarb/kube-port-forward
+	// fullPath := fmt.Sprintf("/api/v1/namespaces/%s/pods/%s/portforward",
+	// 	hsh.DaemonSet.Namespace, podName)
+	// transport, upgrader, err := spdy.RoundTripperFor(hsh.k8sObj.KubernetesClient.config)
+	// if err != nil {
+	// 	return nil, err
+	// }
+	// hostIP := strings.TrimLeft(req.RestConfig.Host, "htps:/")
+	// dialer := spdy.NewDialer(upgrader, &http.Client{Transport: transport}, http.MethodPost, &url.URL{Scheme: "http", Path: path, Host: hostIP})
+	return nil, nil
+}
+
+// sendAllPodsHTTPGETRequest fills the raw byte response in the envelope and the node name, but not the GroupVersionKind
+// so the caller is responsible to convert the raw data to some structured data and add the GroupVersionKind details
+func (hsh *HostSensorHandler) sendAllPodsHTTPGETRequest(path string) ([]HostSensorDataEnvelope, error) {
+	podList, err := hsh.getPodList()
+	if err != nil {
+		return nil, fmt.Errorf("failed to sendAllPodsHTTPGETRequest: %v", err)
+	}
+	res := make([]HostSensorDataEnvelope, 0, len(podList))
+	resLock := sync.Mutex{}
+	wg := sync.WaitGroup{}
+	wg.Add(len(podList))
+	for podName := range podList {
+		go func(podName, path string) {
+			defer wg.Done()
+			resBytes, err := hsh.HTTPGetToPod(podName, path)
+			if err != nil {
+				fmt.Printf("In sendAllPodsHTTPGETRequest failed to get data '%s' from pod '%s': %v", path, podName, err)
+			} else {
+				resLock.Lock()
+				defer resLock.Unlock()
+				res = append(res, HostSensorDataEnvelope{NodeName: podList[podName], Data: resBytes})
+			}
+
+		}(podName, path)
+	}
+	wg.Wait()
+	return res, nil
+}
+
+// return list of
+func (hsh *HostSensorHandler) GetKubeletConfigurations() ([]HostSensorDataEnvelope, error) {
+	// loop over pods and port-forward it to each of them
+	res, err := hsh.sendAllPodsHTTPGETRequest("/kubeletConfigurations")
+	for resIdx := range res {
+		jsonBytes, err := yaml.YAMLToJSON(res[resIdx].Data)
+		if err != nil {
+			fmt.Printf("In GetKubeletConfigurations failed to YAMLToJSON: %v;\n%v", err, res[resIdx])
+		}
+		res[resIdx].Data = jsonBytes
+		kindDet := schema.GroupVersionKind{}
+		if err = json.Unmarshal(jsonBytes, &kindDet); err != nil {
+			fmt.Printf("In GetKubeletConfigurations failed to Unmarshal GroupVersionKind: %v;\n%v", err, jsonBytes)
+		}
+	}
+	return res, err
+}