openfaas output type added

Signed-off-by: Batuhan Apaydın <[email protected]>

config.go

@@ -141,6 +141,15 @@ func getConfig() *types.Configuration {
 	v.SetDefault("Kubeless.Port", 8080)
 	v.SetDefault("Kubeless.Kubeconfig", "")
 	v.SetDefault("Kubeless.MinimumPriority", "")
+
+	v.SetDefault("Openfaas.GatewayNamespace", "openfaas")
+	v.SetDefault("Openfaas.GatewayService", "gateway")
+	v.SetDefault("Openfaas.FunctionName", "")
+	v.SetDefault("Openfaas.FunctionNamespace", "openfaas-fn")
+	v.SetDefault("Openfaas.GatewayPort", 8080)
+	v.SetDefault("Openfaas.Kubeconfig", "")
+	v.SetDefault("Openfaas.MinimumPriority", "")
+
 	v.SetDefault("Webui.URL", "")
 
 	v.SetEnvKeyReplacer(strings.NewReplacer(".", "_"))
@@ -227,6 +236,7 @@ func getConfig() *types.Configuration {
 	c.Kafka.MinimumPriority = checkPriority(c.Kafka.MinimumPriority)
 	c.Pagerduty.MinimumPriority = checkPriority(c.Pagerduty.MinimumPriority)
 	c.Kubeless.MinimumPriority = checkPriority(c.Kubeless.MinimumPriority)
+	c.Openfaas.MinimumPriority = checkPriority(c.Openfaas.MinimumPriority)
 
 	c.Slack.MessageFormatTemplate = getMessageFormatTemplate("Slack", c.Slack.MessageFormat)
 	c.Rocketchat.MessageFormatTemplate = getMessageFormatTemplate("Rocketchat", c.Rocketchat.MessageFormat)

config_example.yaml

@@ -166,5 +166,14 @@ kubeless:
   kubeconfig: "~/.kube/config" # Kubeconfig file to use (only if falcoside is running outside the cluster)
   # minimumpriority: "debug" # minimum priority of event for using this output, order is emergency|alert|critical|error|warning|notice|informational|debug or "" (default)
 
+openfaas:
+  gatewaynamespace: "" # Namespace of OpenFaaS Gateway, "openfaas" (default)
+  gatewayservice: "" # Service of OpenFaaS Gateway, "gateway" (default)
+  functionname: "" # Name of OpenFaaS function, if not empty, OpenFaaS is enabled
+  functionnamespace: "" # Namespace of OpenFaaS function, "openfaas-fn" (default)
+  gatewayport: 8080 # Port of service of OpenFaaS Gateway
+  kubeconfig: "~/.kube/config" # Kubeconfig file to use (only if falcosidekick is running outside the cluster)
+  # minimumpriority: "debug" # minimum priority of event for using this output, order is emergency|alert|critical|error|warning|notice|informational|debug or "" (default)
+
 webui:
   url: "" # WebUI URL, if not empty, WebUI output is enabled

handlers.go

@@ -225,6 +225,10 @@ func forwardEvent(falcopayload types.FalcoPayload) {
 		go kubelessClient.KubelessCall(falcopayload)
 	}
 
+	if config.Openfaas.FunctionName != "" && (falcopayload.Priority >= types.Priority(config.Openfaas.MinimumPriority) || falcopayload.Rule == testRule) {
+		go openfaasClient.OpenfaasCall(falcopayload)
+	}
+
 	if config.WebUI.URL != "" {
 		go webUIClient.WebUIPost(falcopayload)
 	}

main.go

@@ -40,6 +40,7 @@ var (
 	kafkaClient         *outputs.Client
 	pagerdutyClient     *outputs.Client
 	kubelessClient      *outputs.Client
+	openfaasClient      *outputs.Client
 	webUIClient         *outputs.Client
 
 	statsdClient, dogstatsdClient *statsd.Client
@@ -369,6 +370,16 @@ func init() {
 		}
 	}
 
+	if config.Openfaas.FunctionName != "" {
+		var err error
+		openfaasClient, err = outputs.NewOpenfaasClient(config, stats, promStats, statsdClient, dogstatsdClient)
+		if err != nil {
+			log.Printf("[ERROR] : OpenFaaS - %v\n", err)
+		} else {
+			outputs.EnabledOutputs = append(outputs.EnabledOutputs, "OpenFaaS")
+		}
+	}
+
 	log.Printf("[INFO]  : Enabled Outputs : %s\n", outputs.EnabledOutputs)
 }
 

outputs/constants.go

@@ -37,4 +37,5 @@ const (
 	Orange    string = "#ff5400"
 
 	Kubeless string = "Kubeless"
+	Openfaas string = "Openfaas"
 )

outputs/openfaas.go

@@ -0,0 +1,84 @@
+package outputs
+
+import (
+	"context"
+	"encoding/json"
+	"log"
+	"strconv"
+
+	"github.com/DataDog/datadog-go/statsd"
+	"github.com/google/uuid"
+	"k8s.io/client-go/kubernetes"
+	"k8s.io/client-go/tools/clientcmd"
+
+	"github.com/falcosecurity/falcosidekick/types"
+)
+
+// NewOpenfaasClient returns a new output.Client for accessing Kubernetes.
+func NewOpenfaasClient(config *types.Configuration, stats *types.Statistics, promStats *types.PromStatistics, statsdClient, dogstatsdClient *statsd.Client) (*Client, error) {
+	if config.Openfaas.Kubeconfig != "" {
+		restConfig, err := clientcmd.BuildConfigFromFlags("", config.Openfaas.Kubeconfig)
+		if err != nil {
+			return nil, err
+		}
+		clientset, err := kubernetes.NewForConfig(restConfig)
+		if err != nil {
+			return nil, err
+		}
+		return &Client{
+			OutputType:       "OpenFaaS",
+			Config:           config,
+			Stats:            stats,
+			PromStats:        promStats,
+			StatsdClient:     statsdClient,
+			DogstatsdClient:  dogstatsdClient,
+			KubernetesClient: clientset,
+		}, nil
+	}
+	return NewClient(
+		"OpenFaaS",
+		"http://"+config.Openfaas.GatewayService+"."+config.Openfaas.GatewayNamespace+":"+strconv.Itoa(config.Openfaas.GatewayPort)+"/function/"+config.Openfaas.FunctionName+"."+config.Openfaas.FunctionNamespace,
+		config,
+		stats,
+		promStats,
+		statsdClient,
+		dogstatsdClient,
+	)
+}
+
+// OpenfaasCall .
+func (c *Client) OpenfaasCall(falcopayload types.FalcoPayload) {
+	c.Stats.Openfaas.Add(Total, 1)
+
+	if c.Config.Openfaas.Kubeconfig != "" {
+		str, _ := json.Marshal(falcopayload)
+		req := c.KubernetesClient.CoreV1().RESTClient().Post().AbsPath("/api/v1/namespaces/" + c.Config.Openfaas.GatewayNamespace + "/services/" + c.Config.Openfaas.GatewayService + ":" + strconv.Itoa(c.Config.Openfaas.GatewayPort) + "/proxy" + "/function/" + c.Config.Openfaas.FunctionName + "." + c.Config.Openfaas.FunctionNamespace).Body(str)
+		req.SetHeader("event-id", uuid.New().String())
+		req.SetHeader("Content-Type", "application/json")
+		req.SetHeader("User-Agent", "Falcosidekick")
+
+		res := req.Do(context.TODO())
+		rawbody, err := res.Raw()
+		if err != nil {
+			go c.CountMetric(Outputs, 1, []string{"output:OpenFaaS", "status:error"})
+			c.Stats.Openfaas.Add(Error, 1)
+			c.PromStats.Outputs.With(map[string]string{"destination": "OpenFaaS", "status": Error}).Inc()
+			log.Printf("[ERROR] : Openfaas - %v\n", err)
+			return
+		}
+		log.Printf("[INFO]  : OpenFaaS - Function Response : %v\n", string(rawbody))
+	} else {
+		err := c.Post(falcopayload)
+		if err != nil {
+			go c.CountMetric(Outputs, 1, []string{"output:OpenFaaS", "status:error"})
+			c.Stats.Openfaas.Add(Error, 1)
+			c.PromStats.Outputs.With(map[string]string{"destination": "OpenFaaS", "status": Error}).Inc()
+			log.Printf("[ERROR] : OpenFaaS - %v\n", err)
+			return
+		}
+	}
+	log.Printf("[INFO]  : OpenFaaS - Call Function \"%v\" OK\n", c.Config.Openfaas.FunctionName+"."+c.Config.Openfaas.FunctionNamespace)
+	go c.CountMetric(Outputs, 1, []string{"output:OpenFaaS", "status:ok"})
+	c.Stats.Openfaas.Add(OK, 1)
+	c.PromStats.Outputs.With(map[string]string{"destination": "OpenFaaS", "status": OK}).Inc()
+}

stats.go

@@ -51,6 +51,7 @@ func getInitStats() *types.Statistics {
 		Kafka:             getOutputNewMap("kafka"),
 		Pagerduty:         getOutputNewMap("pagerduty"),
 		Kubeless:          getOutputNewMap("kubeless"),
+		Openfaas:          getOutputNewMap("openfaas"),
 		WebUI:             getOutputNewMap("webui"),
 	}
 	stats.Falco.Add(outputs.Emergency, 0)

types/types.go

@@ -50,6 +50,7 @@ type Configuration struct {
 	Kafka         kafkaConfig
 	Pagerduty     PagerdutyConfig
 	Kubeless      kubelessConfig
+	Openfaas      openfaasConfig
 	WebUI         WebUIOutputConfig
 }
 
@@ -274,6 +275,16 @@ type kubelessConfig struct {
 	MinimumPriority string
 }
 
+type openfaasConfig struct {
+	GatewayNamespace  string
+	GatewayService    string
+	FunctionName      string
+	FunctionNamespace string
+	GatewayPort       int
+	Kubeconfig        string
+	MinimumPriority   string
+}
+
 // WebUIOutputConfig represents parameters for WebUI
 type WebUIOutputConfig struct {
 	URL string
@@ -314,6 +325,7 @@ type Statistics struct {
 	Pagerduty         *expvar.Map
 	CloudEvents       *expvar.Map
 	Kubeless          *expvar.Map
+	Openfaas          *expvar.Map
 	WebUI             *expvar.Map
 }