added prereq check for ipv4 forwarding and for wireguard

netclient/config/config.go

@@ -203,7 +203,6 @@ func readConfig() *ClientConfig {
 	f, err := os.Open(file)
 	if err != nil {
 		nofile = true
-		fmt.Println("Could not access " + home + "/.netconfig,  proceeding...")
 	}
 	defer f.Close()
 

netclient/main.go

@@ -9,6 +9,7 @@ import (
 	"os"
         "os/exec"
         "strconv"
+	"strings"
 	"log"
 )
 
@@ -36,7 +37,8 @@ func main() {
 	taccesskey := flag.String("k", "badkey", "an access key generated by the server and used for one-time access (install only)")
 	tserver := flag.String("s", "localhost:50051", "The location (including port) of the remote gRPC server.")
 	tgroup := flag.String("g", "badgroup", "The node group you are attempting to join.")
-	tnoauto := flag.Bool("na", false, "No auto mode. If true, netmaker will not be installed as a system service and you will have to retrieve updates manually via checkin command.")
+	tnoauto := flag.Bool("na", false, "No auto mode. If true, netmclient will not be installed as a system service and you will have to retrieve updates manually via checkin command.")
+	tnoforward := flag.Bool("nf", false, "No Forward mode. If true, netclient will not check for IP forwarding. This may break functionality")
 	command := flag.String("c", "required", "The command to run")
 
 
@@ -61,12 +63,35 @@ func main() {
          }
 
 
+	_, err = exec.LookPath("wg")
+	if err != nil {
+		log.Println(err)
+		log.Fatal("WireGuard not installed. Please install WireGuard (wireguard-tools) and try again.")
+	}
+
         switch *command {
 		case "required":
                         fmt.Println("command flag 'c' is required. Pick one of |install|checkin|update|remove|")
                         os.Exit(1)
 			log.Fatal("Exiting")
                 case "install":
+			if !*tnoforward {
+				forward := exec.Command("sysctl", "net.ipv4.ip_forward")
+				out, err := forward.Output()
+
+				if err != nil {
+					log.Fatal(err)
+				}
+				//s := strings.Split(string(out), " ", "\n")
+				s := strings.Fields(string(out))
+				if err != nil {
+					log.Fatal(err)
+				}
+				if s[2] != "1" {
+					log.Fatal("It is recommended to enable IP Forwarding. Current status is: " +  s[2] + ", but should be 1. if you would like to run without IP Forwarding, re-run with flag '-nf true'")
+				}
+			}
+
 			fmt.Println("Beginning agent installation.")
 			err := functions.Install(*taccesskey, *tpassword, *tserver, *tgroup, *tnoauto)
 			if err != nil {