ARP live rescan timeout option

README.md

@@ -69,10 +69,10 @@ wait 5 seconds before exiting to receive delayed reply packets, by default `sx`
 ./sx arp --exit-delay 5s 192.168.0.1/24
 ```
 
-Live scan mode that rescans network every second:
+Live scan mode that rescans network every 10 seconds:
 
 ```
-./sx arp 192.168.0.1/24 --live
+./sx arp 192.168.0.1/24 --live 10s
 ```
 
 ### TCP scan
@@ -286,13 +286,13 @@ As an example of scan composition, you can combine ARP and TCP SYN scans to crea
 Start live ARP scan and save results to `arp.cache` file:
 
 ```
-./sx arp 192.168.0.1/24 --live --json | tee arp.cache
+./sx arp 192.168.0.1/24 --live 10s --json | tee arp.cache
 ```
 
 In another terminal start TCP SYN scan:
 
 ```
-while true; do cat arp.cache | ./sx tcp -p 1-65535 192.168.0.1/24 --json 2> /dev/null; sleep 10; done
+while true; do cat arp.cache | ./sx tcp -p 1-65535 192.168.0.1/24 --json 2> /dev/null; sleep 30; done
 ```
 
 ## Usage help

command/arp.go

@@ -15,10 +15,13 @@ import (
 	"github.com/v-byte-cpu/sx/pkg/scan/arp"
 )
 
-var arpLiveModeFlag bool
+var (
+	cliARPLiveTimeoutFlag string
+	cliARPLiveTimeout     time.Duration
+)
 
 func init() {
-	arpCmd.Flags().BoolVar(&arpLiveModeFlag, "live", false, "enable live mode")
+	arpCmd.Flags().StringVar(&cliARPLiveTimeoutFlag, "live", "", "enable live mode")
 	rootCmd.AddCommand(arpCmd)
 }
 
@@ -32,6 +35,12 @@ var arpCmd = &cobra.Command{
 		}
 		return nil
 	},
+	PreRunE: func(cmd *cobra.Command, args []string) (err error) {
+		if len(cliARPLiveTimeoutFlag) > 0 {
+			cliARPLiveTimeout, err = time.ParseDuration(cliARPLiveTimeoutFlag)
+		}
+		return
+	},
 	RunE: func(cmd *cobra.Command, args []string) (err error) {
 		var r *scan.Range
 		if r, err = parseScanRange(args[0]); err != nil {
@@ -45,7 +54,7 @@ var arpCmd = &cobra.Command{
 		if logger, err = getLogger("arp", os.Stdout); err != nil {
 			return err
 		}
-		if arpLiveModeFlag {
+		if cliARPLiveTimeout > 0 {
 			logger = log.NewUniqueLogger(logger)
 		}
 
@@ -61,9 +70,8 @@ var arpCmd = &cobra.Command{
 
 func newARPScanMethod(ctx context.Context) *arp.ScanMethod {
 	var reqgen scan.RequestGenerator = scan.NewIPRequestGenerator(scan.NewIPGenerator())
-	if arpLiveModeFlag {
-		// TODO rescanTimeout option
-		reqgen = scan.NewLiveRequestGenerator(reqgen, 1*time.Second)
+	if cliARPLiveTimeout > 0 {
+		reqgen = scan.NewLiveRequestGenerator(reqgen, cliARPLiveTimeout)
 	}
 	pktgen := scan.NewPacketMultiGenerator(arp.NewPacketFiller(), runtime.NumCPU())
 	psrc := scan.NewPacketSource(reqgen, pktgen)