Merge 5a8856350d into ca9f644bcc

backend/docs/docs.go

@@ -370,7 +370,7 @@ const docTemplate = `{
         },
         "/rescan": {
             "get": {
-                "description": "Manually trigger rescan",
+                "description": "Manually trigger rescan and wait until the DB is updated",
                 "produces": [
                     "application/json"
                 ],

backend/docs/swagger.json

@@ -363,7 +363,7 @@
         },
         "/rescan": {
             "get": {
-                "description": "Manually trigger rescan",
+                "description": "Manually trigger rescan and wait until the DB is updated",
                 "produces": [
                     "application/json"
                 ],

backend/docs/swagger.yaml

@@ -345,7 +345,7 @@ paths:
       - network
   /rescan:
     get:
-      description: Manually trigger rescan
+      description: Manually trigger rescan and wait until the DB is updated
       produces:
       - application/json
       responses:

backend/internal/api/api-system.go

@@ -25,14 +25,14 @@ func getVersion(c *gin.Context) {
 
 // triggerRescan godoc
 // @Summary      Rescan all interfaces now
-// @Description  Manually trigger rescan
+// @Description  Manually trigger rescan and wait until the DB is updated
 // @Tags         system
 // @Produce      json
 // @Success      200  {string}  string  "OK"
 // @Router       /rescan [get]
 func triggerRescan(c *gin.Context) {
-	routines.ScanRestart()
-	c.Status(http.StatusOK)
+	routines.ScanNow()
+	c.IndentedJSON(http.StatusOK, "OK")
 }
 
 // getConfig godoc

backend/internal/arp/arpscan.go

@@ -2,7 +2,11 @@ package arp
 
 import (
 	"log/slog"
+	"net"
+	"os"
 	"os/exec"
+	"sort"
+	"strconv"
 	"strings"
 	"time"
 
@@ -72,17 +76,13 @@ func Scan(ifaces, args string, strs []string) []models.Host {
 	var foundHosts = []models.Host{}
 	arpArgs = args
 
-	if ifaces != "" {
+	p = resolveScanInterfaces(ifaces)
+	for _, iface := range p {
+		slog.Debug("Scanning interface " + iface)
+		text = scanIface(iface)
+		slog.Debug("Found IPs: \n" + text)
 
-		p = strings.Split(ifaces, " ")
-
-		for _, iface := range p {
-			slog.Debug("Scanning interface " + iface)
-			text = scanIface(iface)
-			slog.Debug("Found IPs: \n" + text)
-
-			foundHosts = append(foundHosts, parseOutput(text, iface)...)
-		}
+		foundHosts = append(foundHosts, parseOutput(text, iface)...)
 	}
 
 	for _, s := range strs {
@@ -96,3 +96,192 @@ func Scan(ifaces, args string, strs []string) []models.Host {
 
 	return foundHosts
 }
+
+func resolveScanInterfaces(ifaces string) []string {
+	configured := strings.Fields(ifaces)
+	available := usableInterfaceMap()
+	auto := autoScanInterfaces(available)
+	selected, invalid, usedAuto := selectScanInterfaces(configured, available, auto)
+
+	if len(invalid) > 0 {
+		slog.Warn("Ignoring unavailable scan interfaces", "ifaces", strings.Join(invalid, " "))
+	}
+	if usedAuto && len(selected) > 0 {
+		slog.Warn("Using auto-detected scan interfaces", "ifaces", strings.Join(selected, " "))
+	}
+
+	return selected
+}
+
+func selectScanInterfaces(configured []string, available map[string]bool, auto []string) ([]string, []string, bool) {
+	if len(configured) == 0 {
+		return uniqueStrings(auto), nil, len(auto) > 0
+	}
+
+	var selected []string
+	var invalid []string
+	for _, iface := range configured {
+		if available[iface] {
+			selected = appendUniqueString(selected, iface)
+			continue
+		}
+		invalid = appendUniqueString(invalid, iface)
+	}
+
+	if len(selected) > 0 {
+		return selected, invalid, false
+	}
+
+	return uniqueStrings(auto), invalid, len(auto) > 0
+}
+
+func usableInterfaceMap() map[string]bool {
+	interfaces, err := net.Interfaces()
+	if err != nil {
+		slog.Warn("Cannot list network interfaces", "err", err)
+		return nil
+	}
+
+	available := make(map[string]bool)
+	for _, iface := range interfaces {
+		if isUsableInterface(iface) {
+			available[iface.Name] = true
+		}
+	}
+
+	return available
+}
+
+func isUsableInterface(iface net.Interface) bool {
+	if iface.Flags&net.FlagUp == 0 || iface.Flags&net.FlagLoopback != 0 {
+		return false
+	}
+
+	addrs, err := iface.Addrs()
+	if err != nil {
+		slog.Debug("Cannot list interface addresses", "iface", iface.Name, "err", err)
+		return false
+	}
+
+	for _, addr := range addrs {
+		if hasUsableIPv4(addr) {
+			return true
+		}
+	}
+
+	return false
+}
+
+func hasUsableIPv4(addr net.Addr) bool {
+	ipNet, ok := addr.(*net.IPNet)
+	if !ok {
+		return false
+	}
+
+	ip := ipNet.IP.To4()
+	return ip != nil && !ip.IsLoopback() && !ip.IsLinkLocalUnicast()
+}
+
+func autoScanInterfaces(available map[string]bool) []string {
+	if len(available) == 0 {
+		return nil
+	}
+
+	ifaces := defaultRouteInterfaces(available)
+	if len(ifaces) > 0 {
+		return ifaces
+	}
+
+	for iface := range available {
+		if isVirtualInterface(iface) {
+			continue
+		}
+		ifaces = append(ifaces, iface)
+	}
+	sort.Strings(ifaces)
+	return ifaces
+}
+
+func defaultRouteInterfaces(available map[string]bool) []string {
+	data, err := os.ReadFile("/proc/net/route")
+	if err != nil {
+		slog.Debug("Cannot read default routes", "err", err)
+		return nil
+	}
+
+	var ifaces []string
+	minMetric := -1
+	for _, line := range strings.Split(string(data), "\n")[1:] {
+		fields := strings.Fields(line)
+		if len(fields) < 7 || fields[1] != "00000000" {
+			continue
+		}
+
+		iface := fields[0]
+		if !available[iface] || isVirtualInterface(iface) {
+			continue
+		}
+
+		metric, err := strconv.Atoi(fields[6])
+		if err != nil {
+			metric = 0
+		}
+
+		switch {
+		case minMetric == -1 || metric < minMetric:
+			minMetric = metric
+			ifaces = []string{iface}
+		case metric == minMetric:
+			ifaces = appendUniqueString(ifaces, iface)
+		}
+	}
+
+	sort.Strings(ifaces)
+	return ifaces
+}
+
+func isVirtualInterface(iface string) bool {
+	prefixes := []string{
+		"br-",
+		"docker",
+		"lxc",
+		"tailscale",
+		"tap",
+		"tun",
+		"vboxnet",
+		"veth",
+		"virbr",
+		"vmnet",
+		"wg",
+	}
+
+	for _, prefix := range prefixes {
+		if strings.HasPrefix(iface, prefix) {
+			return true
+		}
+	}
+
+	return false
+}
+
+func uniqueStrings(values []string) []string {
+	var out []string
+	for _, value := range values {
+		out = appendUniqueString(out, value)
+	}
+	return out
+}
+
+func appendUniqueString(values []string, value string) []string {
+	if value == "" {
+		return values
+	}
+
+	for _, item := range values {
+		if item == value {
+			return values
+		}
+	}
+
+	return append(values, value)
+}

backend/internal/arp/arpscan_test.go

@@ -0,0 +1,69 @@
+package arp
+
+import (
+	"reflect"
+	"testing"
+)
+
+func TestSelectScanInterfacesKeepsValidConfiguredInterfaces(t *testing.T) {
+	available := map[string]bool{
+		"enp6s0": true,
+		"wlo1":   true,
+	}
+
+	selected, invalid, usedAuto := selectScanInterfaces(
+		[]string{"enp6s0", "missing0"},
+		available,
+		[]string{"wlo1"},
+	)
+
+	if !reflect.DeepEqual(selected, []string{"enp6s0"}) {
+		t.Fatalf("selected = %#v, want enp6s0", selected)
+	}
+	if !reflect.DeepEqual(invalid, []string{"missing0"}) {
+		t.Fatalf("invalid = %#v, want missing0", invalid)
+	}
+	if usedAuto {
+		t.Fatal("usedAuto = true, want false")
+	}
+}
+
+func TestSelectScanInterfacesFallsBackWhenAllConfiguredInterfacesAreInvalid(t *testing.T) {
+	available := map[string]bool{
+		"enp6s0": true,
+	}
+
+	selected, invalid, usedAuto := selectScanInterfaces(
+		[]string{"enP8p1s0"},
+		available,
+		[]string{"enp6s0"},
+	)
+
+	if !reflect.DeepEqual(selected, []string{"enp6s0"}) {
+		t.Fatalf("selected = %#v, want enp6s0", selected)
+	}
+	if !reflect.DeepEqual(invalid, []string{"enP8p1s0"}) {
+		t.Fatalf("invalid = %#v, want enP8p1s0", invalid)
+	}
+	if !usedAuto {
+		t.Fatal("usedAuto = false, want true")
+	}
+}
+
+func TestSelectScanInterfacesUsesAutoWhenConfigIsBlank(t *testing.T) {
+	selected, invalid, usedAuto := selectScanInterfaces(
+		nil,
+		map[string]bool{"enp6s0": true},
+		[]string{"enp6s0"},
+	)
+
+	if !reflect.DeepEqual(selected, []string{"enp6s0"}) {
+		t.Fatalf("selected = %#v, want enp6s0", selected)
+	}
+	if len(invalid) != 0 {
+		t.Fatalf("invalid = %#v, want empty", invalid)
+	}
+	if !usedAuto {
+		t.Fatal("usedAuto = false, want true")
+	}
+}

backend/internal/check/network.go

@@ -1,21 +1,385 @@
 package check
 
 import (
+	"bytes"
+	"context"
+	"encoding/xml"
+	"io"
+	"log/slog"
 	"net"
+	"net/http"
+	"net/url"
+	"os/exec"
 	"strings"
+	"time"
 
 	"github.com/aceberg/WatchYourLAN/internal/models"
 )
 
 // DNS - returns DNS names of a host
 func DNS(host models.Host) (name, dns string) {
+	names := lookupHostNames(host.IP)
 
-	dnsNames, _ := net.LookupAddr(host.IP)
-
-	if len(dnsNames) > 0 {
-		name = dnsNames[0]
-		dns = strings.Join(dnsNames, " ")
+	if len(names) > 0 {
+		name = names[0]
+		dns = strings.Join(names, " ")
 	}
 
 	return name, dns
 }
+
+type hostIdentity struct {
+	names    []string
+	hardware string
+}
+
+// EnrichHosts fills host names from local DNS, mDNS and SSDP/UPnP discovery.
+func EnrichHosts(hosts []models.Host) []models.Host {
+	ipSet := make(map[string]struct{})
+
+	for _, host := range hosts {
+		if net.ParseIP(host.IP) != nil {
+			ipSet[host.IP] = struct{}{}
+		}
+	}
+
+	avahi := discoverAvahiBrowse(ipSet)
+	ssdp := discoverSSDP(ipSet)
+
+	for i := range hosts {
+		names := lookupHostNames(hosts[i].IP)
+
+		if identity, ok := avahi[hosts[i].IP]; ok {
+			names = appendUnique(names, identity.names...)
+		}
+
+		if identity, ok := ssdp[hosts[i].IP]; ok {
+			names = appendUnique(names, identity.names...)
+
+			if isUnknownHardware(hosts[i].Hw) && identity.hardware != "" {
+				hosts[i].Hw = identity.hardware
+			}
+		}
+
+		if len(names) > 0 {
+			hosts[i].Name = names[0]
+			hosts[i].DNS = strings.Join(names, " ")
+		}
+	}
+
+	return hosts
+}
+
+func lookupHostNames(ip string) []string {
+	names := []string{}
+
+	dnsNames, _ := net.LookupAddr(ip)
+	names = appendUnique(names, dnsNames...)
+	names = appendUnique(names, getentNames(ip)...)
+	names = appendUnique(names, avahiNames(ip)...)
+
+	return names
+}
+
+func getentNames(ip string) []string {
+	out, ok := runOutput(700*time.Millisecond, "getent", "hosts", ip)
+	if !ok {
+		return nil
+	}
+
+	fields := strings.Fields(out)
+	if len(fields) < 2 {
+		return nil
+	}
+
+	return fields[1:]
+}
+
+func avahiNames(ip string) []string {
+	out, ok := runOutput(900*time.Millisecond, "avahi-resolve-address", ip)
+	if !ok {
+		return nil
+	}
+
+	fields := strings.Fields(out)
+	if len(fields) < 2 {
+		return nil
+	}
+
+	return fields[1:]
+}
+
+func runOutput(timeout time.Duration, name string, args ...string) (string, bool) {
+	ctx, cancel := context.WithTimeout(context.Background(), timeout)
+	defer cancel()
+
+	out, err := exec.CommandContext(ctx, name, args...).Output()
+	if err != nil {
+		return "", false
+	}
+
+	return string(out), true
+}
+
+func discoverAvahiBrowse(targetIPs map[string]struct{}) map[string]hostIdentity {
+	identities := make(map[string]hostIdentity)
+	if len(targetIPs) == 0 {
+		return identities
+	}
+
+	out, ok := runOutput(8*time.Second, "avahi-browse", "-artp")
+	if !ok {
+		return identities
+	}
+
+	for _, line := range strings.Split(out, "\n") {
+		if !strings.HasPrefix(line, "=") {
+			continue
+		}
+
+		parts := strings.Split(line, ";")
+		if len(parts) < 9 {
+			continue
+		}
+
+		ip := strings.TrimSpace(parts[7])
+		if _, ok := targetIPs[ip]; !ok {
+			continue
+		}
+
+		identity := identities[ip]
+		identity.names = appendUnique(identity.names, parts[3], parts[6])
+		identities[ip] = identity
+	}
+
+	return identities
+}
+
+func discoverSSDP(targetIPs map[string]struct{}) map[string]hostIdentity {
+	identities := make(map[string]hostIdentity)
+	if len(targetIPs) == 0 {
+		return identities
+	}
+
+	addr, err := net.ResolveUDPAddr("udp4", "239.255.255.250:1900")
+	if err != nil {
+		return identities
+	}
+
+	conn, err := net.ListenPacket("udp4", ":0")
+	if err != nil {
+		slog.Debug("SSDP listen failed", "err", err)
+		return identities
+	}
+	defer conn.Close()
+
+	message := strings.Join([]string{
+		"M-SEARCH * HTTP/1.1",
+		"HOST:239.255.255.250:1900",
+		`MAN:"ssdp:discover"`,
+		"MX:1",
+		"ST:ssdp:all",
+		"",
+		"",
+	}, "\r\n")
+
+	for i := 0; i < 2; i++ {
+		_, _ = conn.WriteTo([]byte(message), addr)
+	}
+
+	_ = conn.SetDeadline(time.Now().Add(3 * time.Second))
+	seenLocations := make(map[string]struct{})
+
+	for {
+		buffer := make([]byte, 65535)
+		n, remote, err := conn.ReadFrom(buffer)
+		if err != nil {
+			break
+		}
+
+		responseIP, _, err := net.SplitHostPort(remote.String())
+		if err != nil {
+			responseIP = remote.String()
+		}
+
+		headers := parseSSDPHeaders(buffer[:n])
+		location := strings.TrimSpace(headers["location"])
+		if location == "" {
+			continue
+		}
+		if _, seen := seenLocations[location]; seen {
+			continue
+		}
+		seenLocations[location] = struct{}{}
+
+		ip := matchingLocationIP(location, responseIP, targetIPs)
+		if ip == "" {
+			continue
+		}
+
+		identity := identities[ip]
+		desc := fetchSSDPDescription(location)
+		identity.names = appendUnique(identity.names, desc["friendlyName"])
+		identity.hardware = joinNonEmpty(desc["manufacturer"], desc["modelName"], desc["modelNumber"])
+		identities[ip] = identity
+	}
+
+	return identities
+}
+
+func parseSSDPHeaders(payload []byte) map[string]string {
+	headers := make(map[string]string)
+
+	for _, line := range strings.Split(string(payload), "\n") {
+		key, value, ok := strings.Cut(line, ":")
+		if !ok {
+			continue
+		}
+		headers[strings.ToLower(strings.TrimSpace(key))] = strings.TrimSpace(value)
+	}
+
+	return headers
+}
+
+func matchingLocationIP(location, responseIP string, targetIPs map[string]struct{}) string {
+	if _, ok := targetIPs[responseIP]; ok {
+		return responseIP
+	}
+
+	parsed, err := url.Parse(location)
+	if err != nil || parsed.Hostname() == "" {
+		return ""
+	}
+
+	locationIP := net.ParseIP(parsed.Hostname())
+	if locationIP != nil {
+		ip := locationIP.String()
+		if _, ok := targetIPs[ip]; ok {
+			return ip
+		}
+		return ""
+	}
+
+	ips, err := net.LookupHost(parsed.Hostname())
+	if err != nil {
+		return ""
+	}
+	for _, ip := range ips {
+		if _, ok := targetIPs[ip]; ok {
+			return ip
+		}
+	}
+
+	return ""
+}
+
+func fetchSSDPDescription(location string) map[string]string {
+	result := make(map[string]string)
+
+	ctx, cancel := context.WithTimeout(context.Background(), 2*time.Second)
+	defer cancel()
+
+	req, err := http.NewRequestWithContext(ctx, http.MethodGet, location, nil)
+	if err != nil {
+		return result
+	}
+	req.Header.Set("User-Agent", "WatchYourLAN/2.1.4")
+
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		return result
+	}
+	defer resp.Body.Close()
+
+	body, err := io.ReadAll(io.LimitReader(resp.Body, 256*1024))
+	if err != nil {
+		return result
+	}
+
+	return parseSSDPDescription(body)
+}
+
+func parseSSDPDescription(body []byte) map[string]string {
+	result := make(map[string]string)
+	wanted := map[string]struct{}{
+		"friendlyName": {},
+		"manufacturer": {},
+		"modelName":    {},
+		"modelNumber":  {},
+	}
+
+	decoder := xml.NewDecoder(bytes.NewReader(body))
+	current := ""
+
+	for {
+		token, err := decoder.Token()
+		if err != nil {
+			break
+		}
+
+		switch item := token.(type) {
+		case xml.StartElement:
+			if _, ok := wanted[item.Name.Local]; ok {
+				current = item.Name.Local
+			}
+		case xml.CharData:
+			if current != "" {
+				result[current] = cleanName(string(item))
+			}
+		case xml.EndElement:
+			if item.Name.Local == current {
+				current = ""
+			}
+		}
+	}
+
+	return result
+}
+
+func appendUnique(items []string, more ...string) []string {
+	seen := make(map[string]struct{}, len(items)+len(more))
+	out := make([]string, 0, len(items)+len(more))
+
+	for _, item := range append(items, more...) {
+		item = cleanName(item)
+		if item == "" {
+			continue
+		}
+		if _, ok := seen[item]; ok {
+			continue
+		}
+		seen[item] = struct{}{}
+		out = append(out, item)
+	}
+
+	return out
+}
+
+func cleanName(value string) string {
+	value = strings.TrimSpace(value)
+	value = strings.TrimSuffix(value, ".")
+	value = strings.Join(strings.Fields(value), " ")
+
+	if value == "" || net.ParseIP(value) != nil {
+		return ""
+	}
+
+	return value
+}
+
+func isUnknownHardware(value string) bool {
+	value = strings.TrimSpace(value)
+	return value == "" || strings.HasPrefix(value, "(Unknown")
+}
+
+func joinNonEmpty(parts ...string) string {
+	out := []string{}
+	for _, part := range parts {
+		part = cleanName(part)
+		if part != "" {
+			out = append(out, part)
+		}
+	}
+
+	return strings.Join(out, " ")
+}

backend/internal/routines/scan-routine.go

@@ -1,6 +1,9 @@
 package routines
 
 import (
+	"sort"
+	"strings"
+	"sync"
 	"time"
 
 	"github.com/aceberg/WatchYourLAN/internal/arp"
@@ -13,9 +16,21 @@ import (
 	"github.com/aceberg/WatchYourLAN/internal/prometheus"
 )
 
+var scanMu sync.Mutex
+
+// ScanNow runs one scan immediately and waits until DB state is updated.
+func ScanNow() {
+	scanMu.Lock()
+	defer scanMu.Unlock()
+
+	foundHosts := arp.Scan(conf.AppConfig.Ifaces, conf.AppConfig.ArpArgs, conf.AppConfig.ArpStrs)
+	foundHosts = check.EnrichHosts(foundHosts)
+
+	compareHosts(newFoundHostIndex(foundHosts))
+}
+
 func startScan(quit chan bool) {
 	var lastDate, nowDate, plusDate time.Time
-	var foundHosts []models.Host
 
 	for {
 		select {
@@ -27,42 +42,56 @@ func startScan(quit chan bool) {
 
 			if nowDate.After(plusDate) {
 
-				foundHosts = arp.Scan(conf.AppConfig.Ifaces, conf.AppConfig.ArpArgs, conf.AppConfig.ArpStrs)
-
-				// Make map of found hosts
-				foundHostsMap := make(map[string]models.Host)
-				for _, fHost := range foundHosts {
-					foundHostsMap[fHost.Mac] = fHost
-				}
-
-				compareHosts(foundHostsMap)
+				ScanNow()
 
 				lastDate = time.Now()
 			}
 
-			time.Sleep(time.Duration(1) * time.Minute)
+			select {
+			case <-quit:
+				return
+			case <-time.After(time.Duration(1) * time.Minute):
+			}
 		}
 	}
 }
 
-func compareHosts(foundHostsMap map[string]models.Host) {
+func compareHosts(foundHosts *foundHostIndex) {
 
 	allHosts, ok := gdb.Select("now")
 	if !ok {
 		return
 	}
 
+	existingMACCounts := make(map[string]int)
+	for _, aHost := range allHosts {
+		mac := normalizeMAC(aHost.Mac)
+		if mac != "" {
+			existingMACCounts[mac]++
+		}
+	}
+
 	for _, aHost := range allHosts {
 
-		fHost, exists := foundHostsMap[aHost.Mac]
+		mac := normalizeMAC(aHost.Mac)
+		fHost, exists := foundHosts.match(aHost, existingMACCounts[mac] == 1)
 		if exists {
 
 			aHost.Iface = fHost.Iface
 			aHost.IP = fHost.IP
+			if aHost.Name == "" && fHost.Name != "" {
+				aHost.Name = fHost.Name
+			}
+			if aHost.DNS == "" && fHost.DNS != "" {
+				aHost.DNS = fHost.DNS
+			}
+			if isUnknownHardware(aHost.Hw) && fHost.Hw != "" {
+				aHost.Hw = fHost.Hw
+			}
 			aHost.Date = fHost.Date
 			aHost.Now = 1
 
-			delete(foundHostsMap, aHost.Mac)
+			foundHosts.delete(fHost)
 
 		} else {
 			aHost.Now = 0
@@ -81,11 +110,147 @@ func compareHosts(foundHostsMap map[string]models.Host) {
 		}
 	}
 
-	for _, fHost := range foundHostsMap {
+	for _, fHost := range foundHosts.remaining() {
 
-		fHost.Name, fHost.DNS = check.DNS(fHost)
+		if fHost.Name == "" || fHost.DNS == "" {
+			fHost.Name, fHost.DNS = check.DNS(fHost)
+		}
 		notify.Unknown(fHost) // Log and Shoutrrr
 
 		gdb.Update("now", fHost)
 	}
 }
+
+type foundHostIndex struct {
+	hosts     map[string]models.Host
+	keysByIP  map[string][]string
+	keysByMAC map[string][]string
+}
+
+func newFoundHostIndex(hosts []models.Host) *foundHostIndex {
+	index := &foundHostIndex{
+		hosts:     make(map[string]models.Host),
+		keysByIP:  make(map[string][]string),
+		keysByMAC: make(map[string][]string),
+	}
+
+	for _, host := range hosts {
+		key := hostIdentityKey(host)
+		if key == "" {
+			continue
+		}
+
+		index.hosts[key] = host
+
+		if host.IP != "" {
+			index.keysByIP[host.IP] = appendUnique(index.keysByIP[host.IP], key)
+		}
+
+		mac := normalizeMAC(host.Mac)
+		if mac != "" {
+			index.keysByMAC[mac] = appendUnique(index.keysByMAC[mac], key)
+		}
+	}
+
+	return index
+}
+
+func (index *foundHostIndex) match(existing models.Host, allowMACFallback bool) (models.Host, bool) {
+	key := hostIdentityKey(existing)
+	if host, ok := index.hosts[key]; ok {
+		return host, true
+	}
+
+	if existing.IP != "" {
+		if host, ok := index.only(index.keysByIP[existing.IP]); ok {
+			return host, true
+		}
+	}
+
+	mac := normalizeMAC(existing.Mac)
+	if allowMACFallback && mac != "" {
+		if host, ok := index.only(index.keysByMAC[mac]); ok {
+			return host, true
+		}
+	}
+
+	return models.Host{}, false
+}
+
+func (index *foundHostIndex) only(keys []string) (models.Host, bool) {
+	active := make([]string, 0, len(keys))
+	for _, key := range keys {
+		if _, ok := index.hosts[key]; ok {
+			active = append(active, key)
+		}
+	}
+
+	if len(active) != 1 {
+		return models.Host{}, false
+	}
+
+	host, ok := index.hosts[active[0]]
+	return host, ok
+}
+
+func (index *foundHostIndex) delete(host models.Host) {
+	key := hostIdentityKey(host)
+	delete(index.hosts, key)
+}
+
+func (index *foundHostIndex) remaining() []models.Host {
+	keys := make([]string, 0, len(index.hosts))
+	for key := range index.hosts {
+		keys = append(keys, key)
+	}
+	sort.Slice(keys, func(i, j int) bool {
+		return index.hosts[keys[i]].IP < index.hosts[keys[j]].IP
+	})
+
+	hosts := make([]models.Host, 0, len(keys))
+	for _, key := range keys {
+		hosts = append(hosts, index.hosts[key])
+	}
+
+	return hosts
+}
+
+func hostIdentityKey(host models.Host) string {
+	ip := strings.TrimSpace(host.IP)
+	mac := normalizeMAC(host.Mac)
+
+	if mac != "" && ip != "" {
+		return mac + "|" + ip
+	}
+	if mac != "" {
+		return mac
+	}
+	return ip
+}
+
+func normalizeMAC(value string) string {
+	return strings.ToLower(strings.TrimSpace(value))
+}
+
+func appendUnique(items []string, more ...string) []string {
+	seen := make(map[string]struct{}, len(items)+len(more))
+	out := make([]string, 0, len(items)+len(more))
+
+	for _, item := range append(items, more...) {
+		if item == "" {
+			continue
+		}
+		if _, ok := seen[item]; ok {
+			continue
+		}
+		seen[item] = struct{}{}
+		out = append(out, item)
+	}
+
+	return out
+}
+
+func isUnknownHardware(value string) bool {
+	value = strings.TrimSpace(value)
+	return value == "" || strings.HasPrefix(value, "(Unknown")
+}

backend/internal/routines/scan-routine_test.go

@@ -0,0 +1,57 @@
+package routines
+
+import (
+	"testing"
+
+	"github.com/aceberg/WatchYourLAN/internal/models"
+)
+
+func TestFoundHostIndexKeepsSameMACDifferentIPs(t *testing.T) {
+	index := newFoundHostIndex([]models.Host{
+		{IP: "192.168.57.146", Mac: "48:b0:2d:eb:f5:15"},
+		{IP: "192.168.57.209", Mac: "48:b0:2d:eb:f5:15"},
+	})
+
+	host, ok := index.match(models.Host{IP: "192.168.57.209", Mac: "48:b0:2d:eb:f5:15"}, false)
+	if !ok {
+		t.Fatal("expected exact MAC+IP match")
+	}
+	if host.IP != "192.168.57.209" {
+		t.Fatalf("matched wrong IP: %s", host.IP)
+	}
+
+	index.delete(host)
+
+	remaining := index.remaining()
+	if len(remaining) != 1 {
+		t.Fatalf("expected one remaining host, got %d", len(remaining))
+	}
+	if remaining[0].IP != "192.168.57.146" {
+		t.Fatalf("expected 192.168.57.146 to remain, got %s", remaining[0].IP)
+	}
+}
+
+func TestFoundHostIndexUsesMACForSingleAddressChange(t *testing.T) {
+	index := newFoundHostIndex([]models.Host{
+		{IP: "192.168.57.210", Mac: "48:b0:2d:eb:f5:15"},
+	})
+
+	host, ok := index.match(models.Host{IP: "192.168.57.209", Mac: "48:b0:2d:eb:f5:15"}, true)
+	if !ok {
+		t.Fatal("expected single MAC match for address change")
+	}
+	if host.IP != "192.168.57.210" {
+		t.Fatalf("matched wrong IP: %s", host.IP)
+	}
+}
+
+func TestFoundHostIndexDoesNotUseMACFallbackForKnownMultiIPHost(t *testing.T) {
+	index := newFoundHostIndex([]models.Host{
+		{IP: "192.168.57.146", Mac: "48:b0:2d:eb:f5:15"},
+	})
+
+	_, ok := index.match(models.Host{IP: "192.168.57.209", Mac: "48:b0:2d:eb:f5:15"}, false)
+	if ok {
+		t.Fatal("did not expect MAC fallback when same MAC is already known on multiple IPs")
+	}
+}

backend/internal/web/templates/index.html

@@ -8,6 +8,8 @@
   <!--Favicon-->
   <link rel="icon" type="image/x-icon" href="/fs/public/favicon.png">
   <!-- JS & CSS -->
+  <link id="watchyourlan-icons-css" rel="stylesheet" href="/fs/public/vendor/bootstrap-icons/font/bootstrap-icons.min.css">
+  <link id="watchyourlan-theme-css" rel="stylesheet" href="/fs/public/vendor/aceberg-bootswatch-fork/dist/sand/bootstrap.min.css">
   <script type="module" crossorigin src="/fs/public/assets/index.js"></script>
   <link rel="stylesheet" crossorigin href="/fs/public/assets/index.css">
   </head>
@@ -16,4 +18,4 @@
     <div id="root"></div>
   </body>
 </html>
-{{ end }}
+{{ end }}

frontend/package-lock.json

@@ -1,18 +1,21 @@
 {
   "name": "watchyourlan",
-  "version": "2.1.3",
+  "version": "2.1.4",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "watchyourlan",
-      "version": "2.1.3",
+      "version": "2.1.4",
       "dependencies": {
         "@solid-primitives/scheduled": "^1.5.2",
         "@solidjs/router": "^0.15.3",
+        "aceberg-bootswatch-fork": "5.3.3-2",
+        "bootstrap-icons": "1.11.3",
         "solid-js": "^1.9.5"
       },
       "devDependencies": {
+        "@types/node": "22.13.10",
         "typescript": "~5.7.2",
         "vite": "^6.2.0",
         "vite-plugin-solid": "^2.11.2"
@@ -1029,6 +1032,22 @@
       "integrity": "sha512-AYnb1nQyY49te+VRAVgmzfcgjYS91mY5P0TKUDCLEM+gNnA+3T6rWITXRLYCpahpqSQbN5cE+gHpnPyXjHWxcw==",
       "dev": true
     },
+    "node_modules/@types/node": {
+      "version": "22.13.10",
+      "resolved": "https://registry.npmjs.org/@types/node/-/node-22.13.10.tgz",
+      "integrity": "sha512-I6LPUvlRH+O6VRUqYOcMudhaIdUVWfsjnZavnsraHvpBwaEyMN29ry+0UVJhImYL16xsscu0aske3yA+uPOWfw==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "undici-types": "~6.20.0"
+      }
+    },
+    "node_modules/aceberg-bootswatch-fork": {
+      "version": "5.3.3-2",
+      "resolved": "https://registry.npmjs.org/aceberg-bootswatch-fork/-/aceberg-bootswatch-fork-5.3.3-2.tgz",
+      "integrity": "sha512-DE7EB59n718Q+niRQhR1SQf9e6p/Q+U2yBtIbsPCoK1TGgj+n2VYHtcDIyXsbKofWB9D3T/zr5Gkx8EHX9n0jA==",
+      "license": "MIT"
+    },
     "node_modules/babel-plugin-jsx-dom-expressions": {
       "version": "0.39.7",
       "resolved": "https://registry.npmjs.org/babel-plugin-jsx-dom-expressions/-/babel-plugin-jsx-dom-expressions-0.39.7.tgz",
@@ -1070,6 +1089,22 @@
         "@babel/core": "^7.0.0"
       }
     },
+    "node_modules/bootstrap-icons": {
+      "version": "1.11.3",
+      "resolved": "https://registry.npmjs.org/bootstrap-icons/-/bootstrap-icons-1.11.3.tgz",
+      "integrity": "sha512-+3lpHrCw/it2/7lBL15VR0HEumaBss0+f/Lb6ZvHISn1mlK83jjFpooTLsMWbIjJMDjDjOExMsTxnXSIT4k4ww==",
+      "funding": [
+        {
+          "type": "github",
+          "url": "https://github.com/sponsors/twbs"
+        },
+        {
+          "type": "opencollective",
+          "url": "https://opencollective.com/bootstrap"
+        }
+      ],
+      "license": "MIT"
+    },
     "node_modules/browserslist": {
       "version": "4.24.4",
       "resolved": "https://registry.npmjs.org/browserslist/-/browserslist-4.24.4.tgz",
@@ -1509,6 +1544,13 @@
         "node": ">=14.17"
       }
     },
+    "node_modules/undici-types": {
+      "version": "6.20.0",
+      "resolved": "https://registry.npmjs.org/undici-types/-/undici-types-6.20.0.tgz",
+      "integrity": "sha512-Ny6QZ2Nju20vw1SRHe3d9jVu6gJ+4e3+MMpqu7pqE5HT6WsTSlce++GQmK5UXS8mzV8DSYHrQH+Xrf2jVcuKNg==",
+      "dev": true,
+      "license": "MIT"
+    },
     "node_modules/update-browserslist-db": {
       "version": "1.1.3",
       "resolved": "https://registry.npmjs.org/update-browserslist-db/-/update-browserslist-db-1.1.3.tgz",

frontend/package.json

@@ -11,9 +11,12 @@
   "dependencies": {
     "@solid-primitives/scheduled": "^1.5.2",
     "@solidjs/router": "^0.15.3",
+    "aceberg-bootswatch-fork": "5.3.3-2",
+    "bootstrap-icons": "1.11.3",
     "solid-js": "^1.9.5"
   },
   "devDependencies": {
+    "@types/node": "22.13.10",
     "typescript": "~5.7.2",
     "vite": "^6.2.0",
     "vite-plugin-solid": "^2.11.2"

frontend/src/components/Body/CardHead.tsx

@@ -1,11 +1,12 @@
-import { Show } from "solid-js";
+import { Show, createSignal } from "solid-js";
 import { editNames, selectedIDs, setEditNames } from "../../functions/exports";
 import Filter from "../Filter";
 import Search from "../Search";
 import { getHosts } from "../../functions/atstart";
-import { apiDelHost } from "../../functions/api";
+import { apiDelHost, apiRescan } from "../../functions/api";
 
 function CardHead() {
+  const [rescanning, setRescanning] = createSignal(false);
 
   const handleEditNames = (toggle: boolean) => {
     if (!toggle) {
@@ -24,6 +25,20 @@ function CardHead() {
     window.location.href = '/';
   };
 
+  const handleRescan = async () => {
+    if (rescanning()) {
+      return;
+    }
+
+    setRescanning(true);
+    try {
+      await apiRescan();
+      await getHosts();
+    } finally {
+      setRescanning(false);
+    }
+  };
+
   return (
     <div class="row">
       <div class="col-md mt-1 mb-1">
@@ -33,7 +48,18 @@ function CardHead() {
       </div>
       <div class="col-md mt-1 mb-1">
         <div class="d-flex justify-content-between">
-        <Search></Search>
+        <div class="d-flex gap-2">
+          <Search></Search>
+          <button
+            class="btn btn-outline-primary"
+            title="Rescan now"
+            onClick={handleRescan}
+            disabled={rescanning()}
+            style="width: 2.5rem;"
+          >
+            <i class={rescanning() ? "spinner-border spinner-border-sm" : "bi bi-arrow-clockwise"}></i>
+          </button>
+        </div>
         <Show
           when={editNames()}
           fallback={<button class="btn btn-outline-primary" title="Toggle edit" onClick={[handleEditNames, true]}>Edit</button>}

frontend/src/components/Body/TableRow.tsx

@@ -7,6 +7,25 @@ import { debounce } from "@solid-primitives/scheduled";
 function TableRow(_props: any) {
 
   const [name, setName] = createSignal(_props.host.Name);
+
+  const displayName = () => {
+    const currentName = name().trim();
+    if (currentName !== "") {
+      return currentName;
+    }
+
+    const hardware = (_props.host.Hw || "").trim();
+    if (hardware !== "" && !hardware.startsWith("(Unknown")) {
+      return hardware;
+    }
+
+    const mac = (_props.host.Mac || "").trim();
+    if (mac !== "") {
+      return "Unknown " + mac.slice(-5);
+    }
+
+    return "Unknown";
+  };
   
   let now = <i class="bi bi-circle-fill" style="color:var(--bs-gray-500);"></i>;
   if (_props.host.Now == 1) {
@@ -45,7 +64,9 @@ function TableRow(_props: any) {
       <td>
         <Show
           when={editNames()}
-          fallback={name()}
+          fallback={
+            <span class={name().trim() === "" ? "text-muted" : ""}>{displayName()}</span>
+          }
         >
           <input type="text" class="form-control" value={name()}
             onInput={e => handleInput(e.target.value)}></input>

frontend/src/components/Header.tsx

@@ -1,37 +1,39 @@
-import { createSignal } from "solid-js";
+import { onMount } from "solid-js";
 import { appConfig, setAppConfig } from "../functions/exports";
 import { apiGetConfig } from "../functions/api";
 
 function Header() {
-
-  const [themePath, setThemePath] = createSignal('');
-  const [iconsPath, setIconsPath] = createSignal('');
   
   const setCurrentTheme = async () => {
     setAppConfig(await apiGetConfig());
 
     const theme = appConfig().Theme?appConfig().Theme:"sand";
     const color = appConfig().Color?appConfig().Color:"dark";
+    let themePath = "/fs/public/vendor/aceberg-bootswatch-fork/dist/"+theme+"/bootstrap.min.css";
+    let iconsPath = "/fs/public/vendor/bootstrap-icons/font/bootstrap-icons.min.css";
     
-    if (appConfig().NodePath == '') {
-      setThemePath("https://cdn.jsdelivr.net/npm/aceberg-bootswatch-fork@v5.3.3-2/dist/"+theme+"/bootstrap.min.css");
-      setIconsPath("https://cdn.jsdelivr.net/npm/bootstrap-icons@1.11.3/font/bootstrap-icons.css");
-    } else {
-      setThemePath(appConfig().NodePath+"/node_modules/bootswatch/dist/"+theme+"/bootstrap.min.css");
-      setIconsPath(appConfig().NodePath+"/node_modules/bootstrap-icons/font/bootstrap-icons.css");
+    if (appConfig().NodePath != '') {
+      themePath = appConfig().NodePath+"/node_modules/bootswatch/dist/"+theme+"/bootstrap.min.css";
+      iconsPath = appConfig().NodePath+"/node_modules/bootstrap-icons/font/bootstrap-icons.css";
     }
 
+    const themeLink = document.getElementById("watchyourlan-theme-css") as HTMLLinkElement | null;
+    const iconsLink = document.getElementById("watchyourlan-icons-css") as HTMLLinkElement | null;
+    themeLink?.setAttribute("href", themePath);
+    iconsLink?.setAttribute("href", iconsPath);
+
     document.documentElement.setAttribute("data-bs-theme", color);
     color === "dark"
       ? document.documentElement.style.setProperty('--transparent-light', '#ffffff15')
       : document.documentElement.style.setProperty('--transparent-light', '#00000015');
   }
-  setCurrentTheme();
+
+  onMount(() => {
+    setCurrentTheme();
+  });
 
   return (
     <>
-    <link rel="stylesheet" href={iconsPath()}></link> {/* icons */}
-    <link rel="stylesheet" href={themePath()}></link> {/* theme */}
     <nav class="navbar navbar-expand-md navbar-dark bg-primary">
       <div class="container-lg">
         <a class="navbar-brand" href="/">

frontend/src/functions/api.ts

@@ -1,4 +1,4 @@
-export const apiPath = 'http://0.0.0.0:8840';
+export const apiPath = '';
 
 export const apiGetAllHosts = async () => {
   const url = apiPath+'/api/all';
@@ -29,6 +29,12 @@ export const apiTestNotify = async () => {
   await fetch(url);
 };
 
+export const apiRescan = async () => {
+
+  const url = apiPath+'/api/rescan';
+  await fetch(url);
+};
+
 export const apiEditHost = async (id:number, name:string, known:string) => {
 
   const url = apiPath+'/api/edit/'+id+'/'+name+'/'+known;
@@ -81,4 +87,4 @@ export const apiWOL = async (mac:string) => {
   const res = await (await fetch(url)).json();
 
   return res;
-};
+};

frontend/src/functions/atstart.ts

@@ -1,5 +1,5 @@
-import { apiGetAllHosts } from "./api";
-import { allHosts, setAllHosts, setBkpHosts, setIfaces } from "./exports";
+import { apiGetAllHosts, apiGetConfig } from "./api";
+import { appConfig, type Conf, type Host, ifaces as savedIfaces, setAllHosts, setAppConfig, setBkpHosts, setIfaces } from "./exports";
 import { filterAtStart, filterFunc } from "./filter";
 import { sortAtStart } from "./sort";
 
@@ -13,27 +13,51 @@ export function runAtStart() {
 }
 
 export async function getHosts() {
-  const hosts = await apiGetAllHosts();
+  const [hosts, config] = await Promise.all([
+    apiGetAllHosts(),
+    apiGetConfig().catch(() => null),
+  ]);
 
-  if (hosts !== null && hosts.length > 0) {
+  if (config !== null) {
+    setAppConfig(config);
+  }
+
+  if (hosts !== null) {
     setAllHosts(hosts);
     setBkpHosts(hosts);
 
-    listIfaces();
+    listIfaces(hosts, config);
     sortAtStart();
     filterAtStart();
   }
 }
 
-function listIfaces() {
-
-  let ifaces:string[] = [];
-
-  for (let host of allHosts) {
-    if (!ifaces.includes(host.Iface)) {
-      ifaces.push(host.Iface);
+function listIfaces(hosts: Host[], config: Conf | null) {
+  const ifaceOptions: string[] = [];
+  const addIface = (iface: string) => {
+    const trimmed = iface.trim();
+    if (trimmed !== "" && !ifaceOptions.includes(trimmed)) {
+      ifaceOptions.push(trimmed);
     }
+  };
+
+  for (let host of hosts) {
+    addIface(host.Iface);
   }
 
-  setIfaces(ifaces);
-}
+  const configuredIfaces = config?.Ifaces || appConfig().Ifaces;
+  for (let iface of configuredIfaces.split(/\s+/)) {
+    addIface(iface);
+  }
+
+  if (ifaceOptions.length > 0) {
+    setIfaces(ifaceOptions);
+    return;
+  }
+
+  if (savedIfaces().length > 0) {
+    return;
+  }
+
+  setIfaces([]);
+}

frontend/tsconfig.app.json

@@ -5,6 +5,7 @@
     "useDefineForClassFields": true,
     "module": "ESNext",
     "lib": ["ES2020", "DOM", "DOM.Iterable"],
+    "types": [],
     "skipLibCheck": true,
 
     /* Bundler mode */

frontend/tsconfig.node.json

@@ -3,6 +3,7 @@
     "tsBuildInfoFile": "./node_modules/.tmp/tsconfig.node.tsbuildinfo",
     "target": "ES2022",
     "lib": ["ES2023"],
+    "types": ["node"],
     "module": "ESNext",
     "skipLibCheck": true,
 

frontend/vite.config.ts

@@ -1,8 +1,51 @@
 import { defineConfig } from 'vite'
 import solid from 'vite-plugin-solid'
+import { copyFileSync, cpSync, mkdirSync, readdirSync, rmSync } from 'node:fs'
+import { dirname, resolve } from 'node:path'
+import { fileURLToPath } from 'node:url'
+
+const rootDir = dirname(fileURLToPath(import.meta.url))
+
+function copyVendorAssets() {
+  const vendorDir = resolve(rootDir, 'dist/vendor')
+
+  rmSync(vendorDir, { recursive: true, force: true })
+  mkdirSync(vendorDir, { recursive: true })
+
+  const themesDir = resolve(rootDir, 'node_modules/aceberg-bootswatch-fork/dist')
+  for (const theme of readdirSync(themesDir, { withFileTypes: true })) {
+    if (!theme.isDirectory()) {
+      continue
+    }
+
+    const targetDir = resolve(vendorDir, 'aceberg-bootswatch-fork/dist', theme.name)
+    mkdirSync(targetDir, { recursive: true })
+    copyFileSync(
+      resolve(themesDir, theme.name, 'bootstrap.min.css'),
+      resolve(targetDir, 'bootstrap.min.css'),
+    )
+  }
+
+  mkdirSync(resolve(vendorDir, 'bootstrap-icons/font'), { recursive: true })
+  cpSync(
+    resolve(rootDir, 'node_modules/bootstrap-icons/font/bootstrap-icons.min.css'),
+    resolve(vendorDir, 'bootstrap-icons/font/bootstrap-icons.min.css'),
+  )
+  cpSync(
+    resolve(rootDir, 'node_modules/bootstrap-icons/font/fonts'),
+    resolve(vendorDir, 'bootstrap-icons/font/fonts'),
+    { recursive: true },
+  )
+}
 
 export default defineConfig({
-  plugins: [solid()],
+  plugins: [
+    solid(),
+    {
+      name: 'copy-vendor-assets',
+      closeBundle: copyVendorAssets,
+    },
+  ],
   build: {
     rollupOptions: {
       output: {