✨ Add Custom header usage to find the user IP

bouncer.go

@@ -28,6 +28,7 @@ const (
 	crowdsecLapiStreamRoute = "v1/decisions/stream"
 	cacheBannedValue        = "t"
 	cacheNoBannedValue      = "f"
+	xForwardedFor           = "X-Forwarded-For"
 )
 
 // Config the plugin configuration.
@@ -40,6 +41,7 @@ type Config struct {
 	UpdateIntervalSeconds      int64    `json:"updateIntervalSeconds,omitempty"`
 	DefaultDecisionSeconds     int64    `json:"defaultDecisionSeconds,omitempty"`
 	ForwardedHeadersTrustedIPs []string `json:"forwardedheaderstrustedips,omitempty"`
+	ForwardedHeadersCustomName string   `json:"forwardedheaderscustomheader,omitempty"`
 }
 
 // CreateConfig creates the default plugin configuration.
@@ -53,6 +55,7 @@ func CreateConfig() *Config {
 		UpdateIntervalSeconds:      60,
 		DefaultDecisionSeconds:     60,
 		ForwardedHeadersTrustedIPs: []string{},
+		ForwardedHeadersCustomName: xForwardedFor,
 	}
 }
 
@@ -70,6 +73,7 @@ type Bouncer struct {
 	crowdsecMode           string
 	updateInterval         int64
 	defaultDecisionTimeout int64
+	customHeader           string
 	poolStrategy           *ip.PoolStrategy
 	client                 *http.Client
 	cache                  *ttl_map.Heap
@@ -96,6 +100,7 @@ func New(ctx context.Context, next http.Handler, config *Config, name string) (h
 		crowdsecHost:           config.CrowdsecLapiHost,
 		crowdsecKey:            config.CrowdsecLapiKey,
 		updateInterval:         config.UpdateIntervalSeconds,
+		customHeader:           config.ForwardedHeadersCustomName,
 		defaultDecisionTimeout: config.DefaultDecisionSeconds,
 		poolStrategy: &ip.PoolStrategy{
 			Checker: checker,
@@ -198,7 +203,7 @@ func contains(source []string, target string) bool {
 
 // It returns the first IP that is not in the pool, or the empty string otherwise.
 func getRemoteIP(bouncer *Bouncer, req *http.Request) (string, error) {
-	remoteIP := bouncer.poolStrategy.GetIP(req)
+	remoteIP := bouncer.poolStrategy.GetIP(req, bouncer.customHeader)
 	if len(remoteIP) != 0 {
 		return remoteIP, nil
 	}