adding gateway routes for peers

netclient/local/routes_darwin.go

@@ -9,6 +9,44 @@ import (
 	"github.com/gravitl/netmaker/netclient/ncutils"
 )
 
+// GetDefaultRoute - Gets the default route (ip and interface) on a mac machine
+func GetDefaultRoute() (string, string, error) {
+	var ipaddr string
+	var iface string
+	var err error
+	var outLine string
+	output, err := ncutils.RunCmd("netstat -nr", false)
+	for _, line := range strings.Split(strings.TrimSuffix(output, "\n"), "\n") {
+		if strings.Contains(line, "default") {
+			outLine = line
+			break
+		}
+	}
+	space := regexp.MustCompile(`\s+`)
+	outFormatted := space.ReplaceAllString(outLine, " ")
+	if err != nil {
+		return ipaddr, iface, err
+	}
+	outputSlice := strings.Split(string(outFormatted), " ")
+	if !strings.Contains(outputSlice[0], "default") {
+		return ipaddr, iface, fmt.Errorf("could not find default gateway")
+	}
+	ipaddr = outputSlice[1]
+	if err = checkIPAddress(ipaddr); err != nil {
+		return ipaddr, iface, err
+	}
+	iface = outputSlice[3]
+
+	return ipaddr, iface, err
+}
+
+func checkIPAddress(ip string) error {
+	if net.ParseIP(ip) == nil {
+		return fmt.Errorf("IP Address: %s - Invalid", ip)
+	}
+	return nil
+}
+
 // route -n add -net 10.0.0.0/8 192.168.0.254
 // networksetup -setadditionalroutes Ethernet 192.168.1.0 255.255.255.0 10.0.0.2 persistent
 func setRoute(iface string, addr *net.IPNet, address string) error {