#1 implemented mac to ip feature

Makefile

@@ -0,0 +1,38 @@
+.DEFAULT_GOAL := help
+
+.PHONY: setup
+setup: ## Resolve dependencies using Go Modules
+	go mod download
+
+.PHONY: clean
+clean: ## Remove build artifact directory
+	-rm -rfv arping-gui*
+
+.PHONY: lint
+lint: ## Run static code analysis
+	command -v golint >/dev/null 2>&1 || { go get -u golang.org/x/lint/golint; }
+	golint -set_exit_status ./...
+
+.PHONY: run
+run: ## Run app locally
+	go run . -d
+
+.PHONY: build-linux
+build-linux: ## Build linux package
+	command -v fyne >/dev/null 2>&1 || { go get -u fyne.io/fyne/cmd/fyne; }
+	fyne package -os linux -icon icon.png -release
+
+.PHONY: build-mac
+build-mac: ## Build mac package
+	command -v fyne >/dev/null 2>&1 || { go get -u fyne.io/fyne/cmd/fyne; }
+	fyne package -os darwin -icon icon.png -release
+	zip -r arping-gui_macos.zip arping-gui.app
+
+.PHONY: build-win
+build-win: ## Build windows package
+	command -v fyne >/dev/null 2>&1 || { go get -u fyne.io/fyne/cmd/fyne; }
+	fyne package -os windows -icon icon.png -release
+
+.PHONY: help
+help:
+	@grep -E '^[a-zA-Z_-]+:.*?## .*$$' $(MAKEFILE_LIST) | awk 'BEGIN {FS = ":.*?## "}; {printf "\033[36m%-20s\033[0m %s\n", $$1, $$2}'

README.md

@@ -5,13 +5,38 @@ A simple arping-like GUI tool written in Go programming language.
 
 ![screenshot](screenshot.png)
 
+## Key features
+
+- Resolve MAC address from IP address
+- Resolve IP address from MAC address
+- Works on Windows, macOS and Linux
+
 ## Download
 
 See [releases](https://github.com/mikan/arping-gui/releases) page.
 
+## How it works
+
+### IP to MAC
+
+1. Check available network adapter information (e.g. eth0)
+2. Send ICMP ping to the target using native `ping` command
+3. Lookup ARP table using native `arp` command
+
+### IP to MAC
+
+1. Check available network adapter information (e.g. eth0)
+2. Send ICMP ping to the broadcast address using native `ping` command
+3. Lookup ARP table using native `arp` command
+
+## Limitations
+
+- Works only within a local area network
+- IPv6 is not supported
+
 ## License
 
-arping-gui licensed under the BSD 3-Clause License.
+arping-gui licensed under the [BSD 3-Clause License](LICENSE).
 
 ## Author
 

adapter.go

@@ -0,0 +1,70 @@
+package main
+
+import (
+	"encoding/binary"
+	"errors"
+	"fmt"
+	"net"
+	"strings"
+)
+
+type adapter struct {
+	name      string
+	ip        string
+	broadcast string
+}
+
+func adapters() ([]adapter, error) {
+	var adapters []adapter
+	interfaces, err := net.Interfaces()
+	if err != nil {
+		return nil, fmt.Errorf("failed to collect network interface: %w", err)
+	}
+	for _, ifEntry := range interfaces {
+		if ifEntry.HardwareAddr == nil || !strings.Contains(ifEntry.Flags.String(), "up") {
+			continue // ignore odd or down adapters
+		}
+		addresses, err := ifEntry.Addrs()
+		if err != nil || len(addresses) == 0 {
+			continue // ignore unassigned adapters
+		}
+		for _, address := range addresses {
+			if !strings.Contains(address.String(), ".") {
+				continue
+			}
+			ip, n, err := net.ParseCIDR(address.String())
+			if err != nil {
+				continue
+			}
+			broadcast := broadcast(n)
+			adapters = append(adapters, adapter{ifEntry.Name, ip.String(), broadcast})
+		}
+	}
+	if len(adapters) == 0 {
+		return nil, errors.New("no adapters available")
+	}
+	return adapters, nil
+}
+
+func broadcast(n *net.IPNet) string {
+	bc := make(net.IP, len(n.IP.To4()))
+	binary.BigEndian.PutUint32(bc, binary.BigEndian.Uint32(n.IP.To4())|^binary.BigEndian.Uint32(net.IP(n.Mask).To4()))
+	return bc.String()
+}
+
+func adapterNames(adapters []adapter) []string {
+	s := make([]string, len(adapters))
+	for i, a := range adapters {
+		s[i] = fmt.Sprintf("%s [%s]", a.name, a.ip)
+	}
+	return s
+}
+
+func findAdapter(adapters []adapter, name string) adapter {
+	for _, a := range adapters {
+		if strings.HasPrefix(name, a.name) {
+			return a
+		}
+	}
+	return adapter{}
+}

go.sum

@@ -11,6 +11,7 @@ github.com/go-gl/gl v0.0.0-20190320180904-bf2b1f2f34d7 h1:SCYMcCJ89LjRGwEa0tRluN
 github.com/go-gl/gl v0.0.0-20190320180904-bf2b1f2f34d7/go.mod h1:482civXOzJJCPzJ4ZOX/pwvXBWSnzD4OKMdH4ClKGbk=
 github.com/go-gl/glfw/v3.3/glfw v0.0.0-20200222043503-6f7a984d4dc4 h1:WtGNWLvXpe6ZudgnXrq0barxBImvnnJoMEhXAzcbM0I=
 github.com/go-gl/glfw/v3.3/glfw v0.0.0-20200222043503-6f7a984d4dc4/go.mod h1:tQ2UAYgL5IevRw8kRxooKSPJfGvJ9fJQFa0TUsXzTg8=
+github.com/godbus/dbus/v5 v5.0.3 h1:ZqHaoEF7TBzh4jzPmqVhE/5A1z9of6orkAe5uHoAeME=
 github.com/godbus/dbus/v5 v5.0.3/go.mod h1:xhWf0FNVPg57R7Z0UbKHbJfkEywrmjJnf7w5xrFpKfA=
 github.com/goki/freetype v0.0.0-20181231101311-fa8a33aabaff h1:W71vTCKoxtdXgnm1ECDFkfQnpdqAO00zzGXLA5yaEX8=
 github.com/goki/freetype v0.0.0-20181231101311-fa8a33aabaff/go.mod h1:wfqRWLHRBsRgkp5dmbG56SA0DmVtwrF5N3oPdI8t+Aw=

main.go

@@ -1,116 +1,31 @@
 package main
 
 import (
-	"errors"
-	"os/exec"
 	"regexp"
-	"runtime"
-	"strings"
 
-	"fyne.io/fyne"
 	"fyne.io/fyne/app"
+	"fyne.io/fyne/dialog"
 	"fyne.io/fyne/widget"
 )
 
-var macPattern = regexp.MustCompile("([0-9A-Fa-f]{2}[:-]){5}([0-9A-Fa-f]{2})")
-
-type enterEntry struct {
-	widget.Entry
-	tapped func()
-}
-
-func (e *enterEntry) setOnEnter(tapped func()) {
-	e.tapped = tapped
-}
-
-func newEnterEntry() *enterEntry {
-	entry := &enterEntry{}
-	entry.ExtendBaseWidget(entry)
-	return entry
-}
-
-func (e *enterEntry) KeyDown(key *fyne.KeyEvent) {
-	switch key.Name {
-	case fyne.KeyReturn:
-		e.tapped()
-	default:
-		e.Entry.KeyDown(key)
-	}
-}
+var (
+	macPattern = regexp.MustCompile("([0-9A-Fa-f]{2}[:-]){5}([0-9A-Fa-f]{2})")
+	ipPattern  = regexp.MustCompile("(?:[0-9]{1,3}\\.){3}[0-9]{1,3}")
+)
 
 func main() {
 	a := app.New()
 	w := a.NewWindow("arping-gui")
-	macEntry := widget.NewEntry()
-	var macCopyButton *widget.Button
-	macCopyButton = widget.NewButton("Copy to clipboard", func() {
-		w.Clipboard().SetContent(macEntry.Text)
-		macCopyButton.Disable()
-		macCopyButton.SetText("Copied!")
-	})
-	macResult := widget.NewVBox(
-		widget.NewLabel("MAC address:"),
-		macEntry,
-		macCopyButton,
-	)
-	macResult.Hide()
-	ipEntry := newEnterEntry()
-	ipEntry.SetPlaceHolder("ex. 192.168.1.1")
-	var resolveButton *widget.Button
-	resolveButton = widget.NewButton("Resolve", func() {
-		resolveButton.Disable()
-		resolveButton.SetText("Resolving...")
-		defer func() {
-			resolveButton.Enable()
-			resolveButton.SetText("Resolve")
-		}()
-		mac, err := resolve(ipEntry.Text)
-		if err != nil {
-			macEntry.SetText("ERROR: " + err.Error())
-		} else {
-			macEntry.SetText(mac)
-		}
-		macCopyButton.SetText("Copy to clipboard")
-		macCopyButton.Enable()
-		macResult.Show()
-	})
-	ipEntry.setOnEnter(resolveButton.OnTapped)
-	resolveButton.Disable()
-	ipEntry.OnChanged = func(s string) {
-		if len(s) > 0 {
-			resolveButton.Enable()
-		} else {
-			resolveButton.Disable()
-		}
-	}
-	w.SetContent(widget.NewVBox(
-		widget.NewLabel("Target IP address:"),
-		ipEntry,
-		resolveButton,
-		macResult,
-	))
-	w.ShowAndRun()
-}
-
-func resolve(ip string) (string, error) {
-	var pingCmd, arpCmd *exec.Cmd
-	if runtime.GOOS == "windows" {
-		pingCmd = exec.Command("ping", "-n", "1", ip)
-		arpCmd = exec.Command("arp", "-a", ip)
-	} else {
-		pingCmd = exec.Command("ping", "-c", "1", ip)
-		arpCmd = exec.Command("arp", ip)
-	}
-	if err := pingCmd.Run(); err != nil {
-		return "", err
-	}
-	mac, err := arpCmd.Output()
+	w.SetMainMenu(newMainMenu(a, w))
+	adapters, err := adapters()
 	if err != nil {
-		return "", err
-	}
-	matches := macPattern.FindAll(mac, -1)
-	if len(matches) == 0 {
-		return "", errors.New("no data")
+		dialog.NewError(err, w)
 	}
-	return strings.ToLower(strings.ReplaceAll(string(matches[0]), "-", ":")), nil
+	w.SetContent(
+		widget.NewTabContainer(
+			widget.NewTabItem("MAC to IP", newIP2MACTab(w, adapters)),
+			widget.NewTabItem("IP to MAC", newMAC2IPTab(w, adapters)),
+		),
+	)
+	w.ShowAndRun()
 }

resolver.go

@@ -0,0 +1,75 @@
+package main
+
+import (
+	"bufio"
+	"bytes"
+	"errors"
+	"os/exec"
+	"runtime"
+	"strings"
+)
+
+func ip2mac(ip string, adapter adapter) (string, error) {
+	var pingCmd, arpCmd *exec.Cmd
+	switch runtime.GOOS {
+	case "windows":
+		pingCmd = exec.Command("ping", "-n", "1", ip)
+		arpCmd = exec.Command("arp", "-a", ip, "-N", adapter.ip)
+	case "darwin":
+		pingCmd = exec.Command("ping", "-b", adapter.name, "-c", "1", ip)
+		arpCmd = exec.Command("arp", "-i", adapter.name, ip)
+	default:
+		pingCmd = exec.Command("ping", "-I", adapter.name, "-c", "1", ip)
+		arpCmd = exec.Command("arp", "-i", adapter.name, ip)
+	}
+	if err := pingCmd.Run(); err != nil {
+		return "", err
+	}
+	mac, err := arpCmd.Output()
+	if err != nil {
+		return "", err
+	}
+	matches := macPattern.FindAll(mac, -1)
+	if len(matches) == 0 {
+		return "", errors.New("no data")
+	}
+	return strings.ReplaceAll(strings.ToLower(string(matches[0])), "-", ":"), nil
+}
+
+func mac2ip(mac string, adapter adapter) (string, error) {
+	var pingCmd, arpCmd *exec.Cmd
+	switch runtime.GOOS {
+	case "windows":
+		mac = strings.ReplaceAll(strings.ToLower(mac), ":", "-")
+		pingCmd = exec.Command("ping", "-n", "1", adapter.broadcast)
+		arpCmd = exec.Command("arp", "-a", "-N", adapter.ip)
+	case "darwin":
+		mac = strings.ReplaceAll(strings.ToLower(mac), "-", ":")
+		pingCmd = exec.Command("ping", "-b", adapter.name, "-c", "1", adapter.broadcast)
+		arpCmd = exec.Command("arp", "-a", "-i", adapter.name)
+	default:
+		mac = strings.ReplaceAll(strings.ToLower(mac), "-", ":")
+		pingCmd = exec.Command("ping", "-I", adapter.name, "-c", "1", adapter.broadcast, "-b")
+		arpCmd = exec.Command("arp", "-a", "-i", adapter.name)
+	}
+	if err := pingCmd.Run(); err != nil {
+		return "", err
+	}
+	arpOut, err := arpCmd.Output()
+	if err != nil {
+		return "", err
+	}
+	scanner := bufio.NewScanner(bytes.NewReader(arpOut))
+	for scanner.Scan() {
+		line := scanner.Text()
+		if !strings.Contains(line, mac) {
+			continue
+		}
+		matches := ipPattern.FindAllString(line, -1)
+		if len(matches) == 0 {
+			return "", errors.New("no data")
+		}
+		return matches[0], nil
+	}
+	return "", errors.New("no data")
+}