Add MAC and hostname rule items

route/neighbor_resolver_linux.go

@@ -0,0 +1,596 @@
+//go:build linux
+
+package route
+
+import (
+	"bufio"
+	"encoding/binary"
+	"encoding/hex"
+	"net"
+	"net/netip"
+	"os"
+	"slices"
+	"strconv"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/sagernet/fswatch"
+	"github.com/sagernet/sing-box/adapter"
+	E "github.com/sagernet/sing/common/exceptions"
+	"github.com/sagernet/sing/common/logger"
+
+	"github.com/jsimonetti/rtnetlink"
+	"github.com/mdlayher/netlink"
+	"golang.org/x/sys/unix"
+)
+
+var defaultLeaseFiles = []string{
+	"/tmp/dhcp.leases",
+	"/var/lib/dhcp/dhcpd.leases",
+	"/var/lib/dhcpd/dhcpd.leases",
+	"/var/lib/kea/kea-leases4.csv",
+	"/var/lib/kea/kea-leases6.csv",
+}
+
+type neighborResolver struct {
+	logger          logger.ContextLogger
+	leaseFiles      []string
+	access          sync.RWMutex
+	neighborIPToMAC map[netip.Addr]net.HardwareAddr
+	leaseIPToMAC    map[netip.Addr]net.HardwareAddr
+	ipToHostname    map[netip.Addr]string
+	macToHostname   map[string]string
+	watcher         *fswatch.Watcher
+	done            chan struct{}
+}
+
+func newNeighborResolver(resolverLogger logger.ContextLogger, leaseFiles []string) (adapter.NeighborResolver, error) {
+	if len(leaseFiles) == 0 {
+		for _, path := range defaultLeaseFiles {
+			info, err := os.Stat(path)
+			if err == nil && info.Size() > 0 {
+				leaseFiles = append(leaseFiles, path)
+			}
+		}
+	}
+	return &neighborResolver{
+		logger:          resolverLogger,
+		leaseFiles:      leaseFiles,
+		neighborIPToMAC: make(map[netip.Addr]net.HardwareAddr),
+		leaseIPToMAC:    make(map[netip.Addr]net.HardwareAddr),
+		ipToHostname:    make(map[netip.Addr]string),
+		macToHostname:   make(map[string]string),
+		done:            make(chan struct{}),
+	}, nil
+}
+
+func (r *neighborResolver) Start() error {
+	err := r.loadNeighborTable()
+	if err != nil {
+		r.logger.Warn(E.Cause(err, "load neighbor table"))
+	}
+	r.reloadLeaseFiles()
+	go r.subscribeNeighborUpdates()
+	if len(r.leaseFiles) > 0 {
+		watcher, err := fswatch.NewWatcher(fswatch.Options{
+			Path:   r.leaseFiles,
+			Logger: r.logger,
+			Callback: func(_ string) {
+				r.reloadLeaseFiles()
+			},
+		})
+		if err != nil {
+			r.logger.Warn(E.Cause(err, "create lease file watcher"))
+		} else {
+			r.watcher = watcher
+			err = watcher.Start()
+			if err != nil {
+				r.logger.Warn(E.Cause(err, "start lease file watcher"))
+			}
+		}
+	}
+	return nil
+}
+
+func (r *neighborResolver) Close() error {
+	close(r.done)
+	if r.watcher != nil {
+		return r.watcher.Close()
+	}
+	return nil
+}
+
+func (r *neighborResolver) LookupMAC(address netip.Addr) (net.HardwareAddr, bool) {
+	r.access.RLock()
+	defer r.access.RUnlock()
+	mac, found := r.neighborIPToMAC[address]
+	if found {
+		return mac, true
+	}
+	mac, found = r.leaseIPToMAC[address]
+	if found {
+		return mac, true
+	}
+	mac, found = extractMACFromEUI64(address)
+	if found {
+		return mac, true
+	}
+	return nil, false
+}
+
+func (r *neighborResolver) LookupHostname(address netip.Addr) (string, bool) {
+	r.access.RLock()
+	defer r.access.RUnlock()
+	hostname, found := r.ipToHostname[address]
+	if found {
+		return hostname, true
+	}
+	mac, macFound := r.neighborIPToMAC[address]
+	if !macFound {
+		mac, macFound = r.leaseIPToMAC[address]
+	}
+	if !macFound {
+		mac, macFound = extractMACFromEUI64(address)
+	}
+	if macFound {
+		hostname, found = r.macToHostname[mac.String()]
+		if found {
+			return hostname, true
+		}
+	}
+	return "", false
+}
+
+func (r *neighborResolver) loadNeighborTable() error {
+	connection, err := rtnetlink.Dial(nil)
+	if err != nil {
+		return E.Cause(err, "dial rtnetlink")
+	}
+	defer connection.Close()
+	neighbors, err := connection.Neigh.List()
+	if err != nil {
+		return E.Cause(err, "list neighbors")
+	}
+	r.access.Lock()
+	defer r.access.Unlock()
+	for _, neigh := range neighbors {
+		if neigh.Attributes == nil {
+			continue
+		}
+		if neigh.Attributes.LLAddress == nil || len(neigh.Attributes.Address) == 0 {
+			continue
+		}
+		address, ok := netip.AddrFromSlice(neigh.Attributes.Address)
+		if !ok {
+			continue
+		}
+		r.neighborIPToMAC[address] = slices.Clone(neigh.Attributes.LLAddress)
+	}
+	return nil
+}
+
+func (r *neighborResolver) subscribeNeighborUpdates() {
+	connection, err := netlink.Dial(unix.NETLINK_ROUTE, &netlink.Config{
+		Groups: 1 << (unix.RTNLGRP_NEIGH - 1),
+	})
+	if err != nil {
+		r.logger.Warn(E.Cause(err, "subscribe neighbor updates"))
+		return
+	}
+	defer connection.Close()
+	for {
+		select {
+		case <-r.done:
+			return
+		default:
+		}
+		err = connection.SetReadDeadline(time.Now().Add(3 * time.Second))
+		if err != nil {
+			r.logger.Warn(E.Cause(err, "set netlink read deadline"))
+			return
+		}
+		messages, err := connection.Receive()
+		if err != nil {
+			if nerr, ok := err.(net.Error); ok && nerr.Timeout() {
+				continue
+			}
+			select {
+			case <-r.done:
+				return
+			default:
+			}
+			r.logger.Warn(E.Cause(err, "receive neighbor update"))
+			continue
+		}
+		for _, message := range messages {
+			switch message.Header.Type {
+			case unix.RTM_NEWNEIGH:
+				var neighMessage rtnetlink.NeighMessage
+				unmarshalErr := neighMessage.UnmarshalBinary(message.Data)
+				if unmarshalErr != nil {
+					continue
+				}
+				if neighMessage.Attributes == nil {
+					continue
+				}
+				if neighMessage.Attributes.LLAddress == nil || len(neighMessage.Attributes.Address) == 0 {
+					continue
+				}
+				address, ok := netip.AddrFromSlice(neighMessage.Attributes.Address)
+				if !ok {
+					continue
+				}
+				r.access.Lock()
+				r.neighborIPToMAC[address] = slices.Clone(neighMessage.Attributes.LLAddress)
+				r.access.Unlock()
+			case unix.RTM_DELNEIGH:
+				var neighMessage rtnetlink.NeighMessage
+				unmarshalErr := neighMessage.UnmarshalBinary(message.Data)
+				if unmarshalErr != nil {
+					continue
+				}
+				if neighMessage.Attributes == nil || len(neighMessage.Attributes.Address) == 0 {
+					continue
+				}
+				address, ok := netip.AddrFromSlice(neighMessage.Attributes.Address)
+				if !ok {
+					continue
+				}
+				r.access.Lock()
+				delete(r.neighborIPToMAC, address)
+				r.access.Unlock()
+			}
+		}
+	}
+}
+
+func (r *neighborResolver) reloadLeaseFiles() {
+	leaseIPToMAC := make(map[netip.Addr]net.HardwareAddr)
+	ipToHostname := make(map[netip.Addr]string)
+	macToHostname := make(map[string]string)
+	for _, path := range r.leaseFiles {
+		r.parseLeaseFile(path, leaseIPToMAC, ipToHostname, macToHostname)
+	}
+	r.access.Lock()
+	r.leaseIPToMAC = leaseIPToMAC
+	r.ipToHostname = ipToHostname
+	r.macToHostname = macToHostname
+	r.access.Unlock()
+}
+
+func (r *neighborResolver) parseLeaseFile(path string, ipToMAC map[netip.Addr]net.HardwareAddr, ipToHostname map[netip.Addr]string, macToHostname map[string]string) {
+	file, err := os.Open(path)
+	if err != nil {
+		return
+	}
+	defer file.Close()
+	if strings.HasSuffix(path, "kea-leases4.csv") {
+		r.parseKeaCSV4(file, ipToMAC, ipToHostname, macToHostname)
+		return
+	}
+	if strings.HasSuffix(path, "kea-leases6.csv") {
+		r.parseKeaCSV6(file, ipToMAC, ipToHostname, macToHostname)
+		return
+	}
+	if strings.HasSuffix(path, "dhcpd.leases") {
+		r.parseISCDhcpd(file, ipToMAC, ipToHostname, macToHostname)
+		return
+	}
+	r.parseDnsmasqOdhcpd(file, ipToMAC, ipToHostname, macToHostname)
+}
+
+func (r *neighborResolver) parseDnsmasqOdhcpd(file *os.File, ipToMAC map[netip.Addr]net.HardwareAddr, ipToHostname map[netip.Addr]string, macToHostname map[string]string) {
+	now := time.Now().Unix()
+	scanner := bufio.NewScanner(file)
+	for scanner.Scan() {
+		line := scanner.Text()
+		if strings.HasPrefix(line, "duid ") {
+			continue
+		}
+		if strings.HasPrefix(line, "# ") {
+			r.parseOdhcpdLine(line[2:], ipToMAC, ipToHostname, macToHostname)
+			continue
+		}
+		fields := strings.Fields(line)
+		if len(fields) < 4 {
+			continue
+		}
+		expiry, err := strconv.ParseInt(fields[0], 10, 64)
+		if err != nil {
+			continue
+		}
+		if expiry != 0 && expiry < now {
+			continue
+		}
+		if strings.Contains(fields[1], ":") {
+			mac, macErr := net.ParseMAC(fields[1])
+			if macErr != nil {
+				continue
+			}
+			address, addrOK := netip.AddrFromSlice(net.ParseIP(fields[2]))
+			if !addrOK {
+				continue
+			}
+			address = address.Unmap()
+			ipToMAC[address] = mac
+			hostname := fields[3]
+			if hostname != "*" {
+				ipToHostname[address] = hostname
+				macToHostname[mac.String()] = hostname
+			}
+		} else {
+			var mac net.HardwareAddr
+			if len(fields) >= 5 {
+				duid, duidErr := parseDUID(fields[4])
+				if duidErr == nil {
+					mac, _ = extractMACFromDUID(duid)
+				}
+			}
+			address, addrOK := netip.AddrFromSlice(net.ParseIP(fields[2]))
+			if !addrOK {
+				continue
+			}
+			address = address.Unmap()
+			if mac != nil {
+				ipToMAC[address] = mac
+			}
+			hostname := fields[3]
+			if hostname != "*" {
+				ipToHostname[address] = hostname
+				if mac != nil {
+					macToHostname[mac.String()] = hostname
+				}
+			}
+		}
+	}
+}
+
+func (r *neighborResolver) parseOdhcpdLine(line string, ipToMAC map[netip.Addr]net.HardwareAddr, ipToHostname map[netip.Addr]string, macToHostname map[string]string) {
+	fields := strings.Fields(line)
+	if len(fields) < 5 {
+		return
+	}
+	validTime, err := strconv.ParseInt(fields[4], 10, 64)
+	if err != nil {
+		return
+	}
+	if validTime == 0 {
+		return
+	}
+	if validTime > 0 && validTime < time.Now().Unix() {
+		return
+	}
+	hostname := fields[3]
+	if hostname == "-" || strings.HasPrefix(hostname, `broken\x20`) {
+		hostname = ""
+	}
+	if len(fields) >= 8 && fields[2] == "ipv4" {
+		mac, macErr := net.ParseMAC(fields[1])
+		if macErr != nil {
+			return
+		}
+		addressField := fields[7]
+		slashIndex := strings.IndexByte(addressField, '/')
+		if slashIndex >= 0 {
+			addressField = addressField[:slashIndex]
+		}
+		address, addrOK := netip.AddrFromSlice(net.ParseIP(addressField))
+		if !addrOK {
+			return
+		}
+		address = address.Unmap()
+		ipToMAC[address] = mac
+		if hostname != "" {
+			ipToHostname[address] = hostname
+			macToHostname[mac.String()] = hostname
+		}
+		return
+	}
+	var mac net.HardwareAddr
+	duidHex := fields[1]
+	duidBytes, hexErr := hex.DecodeString(duidHex)
+	if hexErr == nil {
+		mac, _ = extractMACFromDUID(duidBytes)
+	}
+	for i := 7; i < len(fields); i++ {
+		addressField := fields[i]
+		slashIndex := strings.IndexByte(addressField, '/')
+		if slashIndex >= 0 {
+			addressField = addressField[:slashIndex]
+		}
+		address, addrOK := netip.AddrFromSlice(net.ParseIP(addressField))
+		if !addrOK {
+			continue
+		}
+		address = address.Unmap()
+		if mac != nil {
+			ipToMAC[address] = mac
+		}
+		if hostname != "" {
+			ipToHostname[address] = hostname
+			if mac != nil {
+				macToHostname[mac.String()] = hostname
+			}
+		}
+	}
+}
+
+func (r *neighborResolver) parseISCDhcpd(file *os.File, ipToMAC map[netip.Addr]net.HardwareAddr, ipToHostname map[netip.Addr]string, macToHostname map[string]string) {
+	scanner := bufio.NewScanner(file)
+	var currentIP netip.Addr
+	var currentMAC net.HardwareAddr
+	var currentHostname string
+	var currentActive bool
+	var inLease bool
+	for scanner.Scan() {
+		line := strings.TrimSpace(scanner.Text())
+		if strings.HasPrefix(line, "lease ") && strings.HasSuffix(line, "{") {
+			ipString := strings.TrimSuffix(strings.TrimPrefix(line, "lease "), " {")
+			parsed, addrOK := netip.AddrFromSlice(net.ParseIP(ipString))
+			if addrOK {
+				currentIP = parsed.Unmap()
+				inLease = true
+				currentMAC = nil
+				currentHostname = ""
+				currentActive = false
+			}
+			continue
+		}
+		if line == "}" && inLease {
+			if currentActive && currentMAC != nil {
+				ipToMAC[currentIP] = currentMAC
+				if currentHostname != "" {
+					ipToHostname[currentIP] = currentHostname
+					macToHostname[currentMAC.String()] = currentHostname
+				}
+			} else {
+				delete(ipToMAC, currentIP)
+				delete(ipToHostname, currentIP)
+			}
+			inLease = false
+			continue
+		}
+		if !inLease {
+			continue
+		}
+		if strings.HasPrefix(line, "hardware ethernet ") {
+			macString := strings.TrimSuffix(strings.TrimPrefix(line, "hardware ethernet "), ";")
+			parsed, macErr := net.ParseMAC(macString)
+			if macErr == nil {
+				currentMAC = parsed
+			}
+		} else if strings.HasPrefix(line, "client-hostname ") {
+			hostname := strings.TrimSuffix(strings.TrimPrefix(line, "client-hostname "), ";")
+			hostname = strings.Trim(hostname, "\"")
+			if hostname != "" {
+				currentHostname = hostname
+			}
+		} else if strings.HasPrefix(line, "binding state ") {
+			state := strings.TrimSuffix(strings.TrimPrefix(line, "binding state "), ";")
+			currentActive = state == "active"
+		}
+	}
+}
+
+func (r *neighborResolver) parseKeaCSV4(file *os.File, ipToMAC map[netip.Addr]net.HardwareAddr, ipToHostname map[netip.Addr]string, macToHostname map[string]string) {
+	scanner := bufio.NewScanner(file)
+	firstLine := true
+	for scanner.Scan() {
+		if firstLine {
+			firstLine = false
+			continue
+		}
+		fields := strings.Split(scanner.Text(), ",")
+		if len(fields) < 10 {
+			continue
+		}
+		if fields[9] != "0" {
+			continue
+		}
+		address, addrOK := netip.AddrFromSlice(net.ParseIP(fields[0]))
+		if !addrOK {
+			continue
+		}
+		address = address.Unmap()
+		mac, macErr := net.ParseMAC(fields[1])
+		if macErr != nil {
+			continue
+		}
+		ipToMAC[address] = mac
+		hostname := ""
+		if len(fields) > 8 {
+			hostname = fields[8]
+		}
+		if hostname != "" {
+			ipToHostname[address] = hostname
+			macToHostname[mac.String()] = hostname
+		}
+	}
+}
+
+func (r *neighborResolver) parseKeaCSV6(file *os.File, ipToMAC map[netip.Addr]net.HardwareAddr, ipToHostname map[netip.Addr]string, macToHostname map[string]string) {
+	scanner := bufio.NewScanner(file)
+	firstLine := true
+	for scanner.Scan() {
+		if firstLine {
+			firstLine = false
+			continue
+		}
+		fields := strings.Split(scanner.Text(), ",")
+		if len(fields) < 14 {
+			continue
+		}
+		if fields[13] != "0" {
+			continue
+		}
+		address, addrOK := netip.AddrFromSlice(net.ParseIP(fields[0]))
+		if !addrOK {
+			continue
+		}
+		address = address.Unmap()
+		var mac net.HardwareAddr
+		if fields[12] != "" {
+			mac, _ = net.ParseMAC(fields[12])
+		}
+		if mac == nil {
+			duid, duidErr := hex.DecodeString(strings.ReplaceAll(fields[1], ":", ""))
+			if duidErr == nil {
+				mac, _ = extractMACFromDUID(duid)
+			}
+		}
+		hostname := ""
+		if len(fields) > 11 {
+			hostname = fields[11]
+		}
+		if mac != nil {
+			ipToMAC[address] = mac
+		}
+		if hostname != "" {
+			ipToHostname[address] = hostname
+			if mac != nil {
+				macToHostname[mac.String()] = hostname
+			}
+		}
+	}
+}
+
+func extractMACFromDUID(duid []byte) (net.HardwareAddr, bool) {
+	if len(duid) < 4 {
+		return nil, false
+	}
+	duidType := binary.BigEndian.Uint16(duid[0:2])
+	hwType := binary.BigEndian.Uint16(duid[2:4])
+	if hwType != 1 {
+		return nil, false
+	}
+	switch duidType {
+	case 1:
+		if len(duid) < 14 {
+			return nil, false
+		}
+		return net.HardwareAddr(slices.Clone(duid[8:14])), true
+	case 3:
+		if len(duid) < 10 {
+			return nil, false
+		}
+		return net.HardwareAddr(slices.Clone(duid[4:10])), true
+	}
+	return nil, false
+}
+
+func extractMACFromEUI64(address netip.Addr) (net.HardwareAddr, bool) {
+	if !address.Is6() {
+		return nil, false
+	}
+	b := address.As16()
+	if b[11] != 0xff || b[12] != 0xfe {
+		return nil, false
+	}
+	return net.HardwareAddr{b[8] ^ 0x02, b[9], b[10], b[13], b[14], b[15]}, true
+}
+
+func parseDUID(s string) ([]byte, error) {
+	cleaned := strings.ReplaceAll(s, ":", "")
+	return hex.DecodeString(cleaned)
+}

route/neighbor_resolver_stub.go

@@ -0,0 +1,14 @@
+//go:build !linux
+
+package route
+
+import (
+	"os"
+
+	"github.com/sagernet/sing-box/adapter"
+	"github.com/sagernet/sing/common/logger"
+)
+
+func newNeighborResolver(_ logger.ContextLogger, _ []string) (adapter.NeighborResolver, error) {
+	return nil, os.ErrInvalid
+}

route/route.go

@@ -408,6 +408,23 @@ func (r *Router) matchRule(
 	buffers []*buf.Buffer, packetBuffers []*N.PacketBuffer, fatalErr error,
 ) {
 	r.searchProcessInfo(ctx, metadata)
+	if r.neighborResolver != nil && metadata.SourceMACAddress == nil && metadata.Source.Addr.IsValid() {
+		mac, macFound := r.neighborResolver.LookupMAC(metadata.Source.Addr)
+		if macFound {
+			metadata.SourceMACAddress = mac
+		}
+		hostname, hostnameFound := r.neighborResolver.LookupHostname(metadata.Source.Addr)
+		if hostnameFound {
+			metadata.SourceHostname = hostname
+			if macFound {
+				r.logger.InfoContext(ctx, "found neighbor: ", mac, ", hostname: ", hostname)
+			} else {
+				r.logger.InfoContext(ctx, "found neighbor hostname: ", hostname)
+			}
+		} else if macFound {
+			r.logger.InfoContext(ctx, "found neighbor: ", mac)
+		}
+	}
 	if metadata.Destination.Addr.IsValid() && r.dnsTransport.FakeIP() != nil && r.dnsTransport.FakeIP().Store().Contains(metadata.Destination.Addr) {
 		domain, loaded := r.dnsTransport.FakeIP().Store().Lookup(metadata.Destination.Addr)
 		if !loaded {

route/router.go

@@ -35,10 +35,13 @@ type Router struct {
 	network           adapter.NetworkManager
 	rules             []adapter.Rule
 	needFindProcess   bool
+	needFindNeighbor  bool
+	leaseFiles        []string
 	ruleSets          []adapter.RuleSet
 	ruleSetMap        map[string]adapter.RuleSet
 	processSearcher   process.Searcher
 	processCache      freelru.Cache[processCacheKey, processCacheEntry]
+	neighborResolver  adapter.NeighborResolver
 	pauseManager      pause.Manager
 	trackers          []adapter.ConnectionTracker
 	platformInterface adapter.PlatformInterface
@@ -58,6 +61,8 @@ func NewRouter(ctx context.Context, logFactory log.Factory, options option.Route
 		rules:             make([]adapter.Rule, 0, len(options.Rules)),
 		ruleSetMap:        make(map[string]adapter.RuleSet),
 		needFindProcess:   hasRule(options.Rules, isProcessRule) || hasDNSRule(dnsOptions.Rules, isProcessDNSRule) || options.FindProcess,
+		needFindNeighbor:  hasRule(options.Rules, isNeighborRule) || hasDNSRule(dnsOptions.Rules, isNeighborDNSRule) || options.FindNeighbor,
+		leaseFiles:        options.DHCPLeaseFiles,
 		pauseManager:      service.FromContext[pause.Manager](ctx),
 		platformInterface: service.FromContext[adapter.PlatformInterface](ctx),
 	}
@@ -117,6 +122,7 @@ func (r *Router) Start(stage adapter.StartStage) error {
 		}
 		r.network.Initialize(r.ruleSets)
 		needFindProcess := r.needFindProcess
+		needFindNeighbor := r.needFindNeighbor
 		for _, ruleSet := range r.ruleSets {
 			metadata := ruleSet.Metadata()
 			if metadata.ContainsProcessRule {
@@ -151,6 +157,24 @@ func (r *Router) Start(stage adapter.StartStage) error {
 			processCache.SetLifetime(200 * time.Millisecond)
 			r.processCache = processCache
 		}
+		r.needFindNeighbor = needFindNeighbor
+		if needFindNeighbor {
+			monitor.Start("initialize neighbor resolver")
+			resolver, err := newNeighborResolver(r.logger, r.leaseFiles)
+			monitor.Finish()
+			if err != nil {
+				if err != os.ErrInvalid {
+					r.logger.Warn(E.Cause(err, "create neighbor resolver"))
+				}
+			} else {
+				err = resolver.Start()
+				if err != nil {
+					r.logger.Warn(E.Cause(err, "start neighbor resolver"))
+				} else {
+					r.neighborResolver = resolver
+				}
+			}
+		}
 	case adapter.StartStatePostStart:
 		for i, rule := range r.rules {
 			monitor.Start("initialize rule[", i, "]")
@@ -182,6 +206,13 @@ func (r *Router) Start(stage adapter.StartStage) error {
 func (r *Router) Close() error {
 	monitor := taskmonitor.New(r.logger, C.StopTimeout)
 	var err error
+	if r.neighborResolver != nil {
+		monitor.Start("close neighbor resolver")
+		err = E.Append(err, r.neighborResolver.Close(), func(closeErr error) error {
+			return E.Cause(closeErr, "close neighbor resolver")
+		})
+		monitor.Finish()
+	}
 	for i, rule := range r.rules {
 		monitor.Start("close rule[", i, "]")
 		err = E.Append(err, rule.Close(), func(err error) error {
@@ -223,6 +254,14 @@ func (r *Router) NeedFindProcess() bool {
 	return r.needFindProcess
 }
 
+func (r *Router) NeedFindNeighbor() bool {
+	return r.needFindNeighbor
+}
+
+func (r *Router) NeighborResolver() adapter.NeighborResolver {
+	return r.neighborResolver
+}
+
 func (r *Router) ResetNetwork() {
 	r.network.ResetNetwork()
 	r.dns.ResetNetwork()

route/rule/rule_default.go

@@ -264,6 +264,16 @@ func NewDefaultRule(ctx context.Context, logger log.ContextLogger, options optio
 		rule.items = append(rule.items, item)
 		rule.allItems = append(rule.allItems, item)
 	}
+	if len(options.SourceMACAddress) > 0 {
+		item := NewSourceMACAddressItem(options.SourceMACAddress)
+		rule.items = append(rule.items, item)
+		rule.allItems = append(rule.allItems, item)
+	}
+	if len(options.SourceHostname) > 0 {
+		item := NewSourceHostnameItem(options.SourceHostname)
+		rule.items = append(rule.items, item)
+		rule.allItems = append(rule.allItems, item)
+	}
 	if len(options.PreferredBy) > 0 {
 		item := NewPreferredByItem(ctx, options.PreferredBy)
 		rule.items = append(rule.items, item)

route/rule/rule_dns.go

@@ -265,6 +265,16 @@ func NewDefaultDNSRule(ctx context.Context, logger log.ContextLogger, options op
 		rule.items = append(rule.items, item)
 		rule.allItems = append(rule.allItems, item)
 	}
+	if len(options.SourceMACAddress) > 0 {
+		item := NewSourceMACAddressItem(options.SourceMACAddress)
+		rule.items = append(rule.items, item)
+		rule.allItems = append(rule.allItems, item)
+	}
+	if len(options.SourceHostname) > 0 {
+		item := NewSourceHostnameItem(options.SourceHostname)
+		rule.items = append(rule.items, item)
+		rule.allItems = append(rule.allItems, item)
+	}
 	if len(options.RuleSet) > 0 {
 		//nolint:staticcheck
 		if options.Deprecated_RulesetIPCIDRMatchSource {

route/rule/rule_item_source_hostname.go

@@ -0,0 +1,42 @@
+package rule
+
+import (
+	"strings"
+
+	"github.com/sagernet/sing-box/adapter"
+)
+
+var _ RuleItem = (*SourceHostnameItem)(nil)
+
+type SourceHostnameItem struct {
+	hostnames   []string
+	hostnameMap map[string]bool
+}
+
+func NewSourceHostnameItem(hostnameList []string) *SourceHostnameItem {
+	rule := &SourceHostnameItem{
+		hostnames:   hostnameList,
+		hostnameMap: make(map[string]bool),
+	}
+	for _, hostname := range hostnameList {
+		rule.hostnameMap[hostname] = true
+	}
+	return rule
+}
+
+func (r *SourceHostnameItem) Match(metadata *adapter.InboundContext) bool {
+	if metadata.SourceHostname == "" {
+		return false
+	}
+	return r.hostnameMap[metadata.SourceHostname]
+}
+
+func (r *SourceHostnameItem) String() string {
+	var description string
+	if len(r.hostnames) == 1 {
+		description = "source_hostname=" + r.hostnames[0]
+	} else {
+		description = "source_hostname=[" + strings.Join(r.hostnames, " ") + "]"
+	}
+	return description
+}

route/rule/rule_item_source_mac_address.go

@@ -0,0 +1,48 @@
+package rule
+
+import (
+	"net"
+	"strings"
+
+	"github.com/sagernet/sing-box/adapter"
+)
+
+var _ RuleItem = (*SourceMACAddressItem)(nil)
+
+type SourceMACAddressItem struct {
+	addresses  []string
+	addressMap map[string]bool
+}
+
+func NewSourceMACAddressItem(addressList []string) *SourceMACAddressItem {
+	rule := &SourceMACAddressItem{
+		addresses:  addressList,
+		addressMap: make(map[string]bool),
+	}
+	for _, address := range addressList {
+		parsed, err := net.ParseMAC(address)
+		if err == nil {
+			rule.addressMap[parsed.String()] = true
+		} else {
+			rule.addressMap[address] = true
+		}
+	}
+	return rule
+}
+
+func (r *SourceMACAddressItem) Match(metadata *adapter.InboundContext) bool {
+	if metadata.SourceMACAddress == nil {
+		return false
+	}
+	return r.addressMap[metadata.SourceMACAddress.String()]
+}
+
+func (r *SourceMACAddressItem) String() string {
+	var description string
+	if len(r.addresses) == 1 {
+		description = "source_mac_address=" + r.addresses[0]
+	} else {
+		description = "source_mac_address=[" + strings.Join(r.addresses, " ") + "]"
+	}
+	return description
+}

route/rule_conds.go

@@ -45,6 +45,14 @@ func isProcessDNSRule(rule option.DefaultDNSRule) bool {
 	return len(rule.ProcessName) > 0 || len(rule.ProcessPath) > 0 || len(rule.ProcessPathRegex) > 0 || len(rule.PackageName) > 0 || len(rule.User) > 0 || len(rule.UserID) > 0
 }
 
+func isNeighborRule(rule option.DefaultRule) bool {
+	return len(rule.SourceMACAddress) > 0 || len(rule.SourceHostname) > 0
+}
+
+func isNeighborDNSRule(rule option.DefaultDNSRule) bool {
+	return len(rule.SourceMACAddress) > 0 || len(rule.SourceHostname) > 0
+}
+
 func isWIFIRule(rule option.DefaultRule) bool {
 	return len(rule.WIFISSID) > 0 || len(rule.WIFIBSSID) > 0
 }