a bunch more dns stuff

Signed-off-by: Jeff Carr <jcarr@wit.com>

Makefile

@@ -11,3 +11,6 @@ build:
 
 update:
 	GO111MODULE="off" go get -v -u -x .
+
+clean:
+	rm control-panel-dns

gui.go

@@ -3,8 +3,11 @@ package main
 
 import 	(
 	"os"
+	"os/user"
 	"log"
+	"net"
 	"git.wit.org/wit/gui"
+	"github.com/davecgh/go-spew/spew"
 )
 
 // This initializes the first window
@@ -31,6 +34,8 @@ func initGUI() {
 
 func addDemoTab(window *gui.Node, title string) {
 	var newNode, g, g2, tb *gui.Node
+	var err error
+	var name string
 
 	newNode = window.NewTab(title)
         log.Println("addDemoTab() newNode.Dump")
@@ -53,6 +58,32 @@ func addDemoTab(window *gui.Node, title string) {
 		s := tb.GetText()
 		log.Println("text =", s)
 	}
+	g2.NewButton("hello", func () {
+		log.Println("world")
+		scanInterfaces()
+	})
+	g2.NewButton("os.Hostname()", func () {
+		name, err = os.Hostname()
+		log.Println("name =", name, err)
+	})
+	g2.NewButton("os.User()", func () {
+		user, _ := user.Current()
+		spew.Dump(user)
+		log.Println("os.Getuid =", os.Getuid())
+	})
+	g2.NewButton("Escalate()", func () {
+		Escalate()
+	})
+	g2.NewButton("LookupAddr(<raw ipv6>) == fire from /etc/hosts", func () {
+		host, err := net.LookupAddr("2600:1700:afd5:6000:b26e:bfff:fe80:3c52")
+		if err != nil {
+			return
+		}
+		log.Println("host =", host)
+	})
+	g2.NewButton("DumpPublicDNSZone(apple.com)", func () {
+		DumpPublicDNSZone("apple.com")
+	})
 }
 
 func myDefaultExit(n *gui.Node) {

main.go

@@ -3,6 +3,8 @@ package main
 
 import 	(
 	"log"
+	"net"
+	"github.com/fsnotify/fsnotify"
 	"git.wit.org/wit/gui"
 	arg "github.com/alexflint/go-arg"
 )
@@ -13,5 +15,72 @@ func main() {
 	log.Println("Toolkit = ", args.Toolkit)
 
 	// gui.InitPlugins([]string{"andlabs"})
+
+	scanInterfaces()
+	watchNetworkInterfaces()
+	go inotifyNetworkInterfaceChanges()
 	gui.Main(initGUI)
 }
+
+func watchNetworkInterfaces() {
+	// Get list of network interfaces
+	interfaces, _ := net.Interfaces()
+
+	// Set up a notification channel
+	notification := make(chan net.Interface)
+
+	// Start goroutine to watch for changes
+	go func() {
+		for {
+			// Check for changes in each interface
+			for _, i := range interfaces {
+				if status := i.Flags & net.FlagUp; status != 0 {
+					notification <- i
+					log.Println("something on i =", i)
+				}
+			}
+		}
+	}()
+}
+
+func inotifyNetworkInterfaceChanges() error {
+	watcher, err := fsnotify.NewWatcher()
+	if err != nil {
+		return err
+	}
+	defer watcher.Close()
+
+	// Watch for network interface changes
+	err = watcher.Add("/sys/class/net")
+	if err != nil {
+		return err
+	}
+	for {
+		select {
+		case event := <-watcher.Events:
+			log.Println("inotifyNetworkInterfaceChanges() event =", event)
+			if event.Op&fsnotify.Create == fsnotify.Create {
+					// Do something on network interface creation
+			}
+		case err := <-watcher.Errors:
+			return err
+		}
+	}
+}
+
+func scanInterfaces() {
+	ifaces, _ := net.Interfaces()
+	for _, i := range ifaces {
+		log.Println(i)
+		addrs, _ := i.Addrs()
+		for _, addr := range addrs {
+			log.Println("\taddr =", addr)
+			switch v := addr.(type) {
+			case *net.IPNet:
+				log.Println("\t\taddr.(type) = *net.IPNet")
+			default:
+				log.Println("\t\taddr.(type) =", v)
+			}
+		}
+	}
+}

unix.go

@@ -0,0 +1,41 @@
+// This creates a simple hello world window
+package main
+
+import 	(
+	"os"
+	"os/exec"
+	"log"
+	"net"
+//	"git.wit.org/wit/gui"
+//	"github.com/davecgh/go-spew/spew"
+)
+
+func CheckSuperuser() bool {
+	return os.Getuid() == 0
+}
+
+func Escalate() {
+	if os.Getuid() != 0 {
+		cmd := exec.Command("sudo", "./control-panel-dns")
+		cmd.Stdin = os.Stdin
+		cmd.Stdout = os.Stdout
+		cmd.Stderr = os.Stderr
+		err := cmd.Run()
+		if err != nil {
+			log.Fatal(err)
+		}
+	}
+}
+
+// You need permission to do a zone transfer. Otherwise:
+// dig +noall +answer +multiline lab.wit.org any 
+// dig +all +multiline fire.lab.wit.org # gives the zonefile header (ttl vals)
+func DumpPublicDNSZone(zone string) {
+	entries, err := net.LookupHost(zone)
+	if err != nil {
+		panic(err)
+	}
+	for _, entry := range entries {
+		log.Println(entry)
+	}
+}