Direct/Freedom outbound: Skip domain resolution and finalRules with dialerProxy

https://github.com/XTLS/Xray-core/pull/6058#issuecomment-5578800461

When using dialerProxy, the target domain should not be resolved to an IP. Also, with dialerProxy freedom is no longer the final outbound, which makes finalRules invalid, so finalRules should not be applied at all.

core/core.go

@@ -19,8 +19,8 @@ import (
 
 var (
 	Version_x byte = 26
-	Version_y byte = 7
-	Version_z byte = 28
+	Version_y byte = 9
+	Version_z byte = 8
 )
 
 var (

go.mod

@@ -1,6 +1,6 @@
 module github.com/xtls/xray-core
 
-go 1.26
+go 1.27
 
 require (
 	github.com/apernet/quic-go v0.61.1-0.20260806010916-184d081eef3e

proxy/freedom/freedom.go

@@ -190,6 +190,12 @@ func (h *Handler) matchFinalRule(network net.Network, address net.Address, port
 func (h *Handler) Init(config *Config, pm policy.Manager) error {
 	h.config = config
 	h.policyManager = pm
+	if h.usesDialerProxy { // freedom is not the final outbound, final rules do not apply
+		if len(config.FinalRules) > 0 {
+			errors.LogWarning(context.Background(), `The "finalRules" setting is ignored when "sockopt.dialerProxy" is set, since freedom is not the final outbound.`)
+		}
+		return nil
+	}
 	h.finalRules = make([]*FinalRule, 0, len(config.FinalRules))
 	for _, rc := range config.FinalRules {
 		rule, err := buildFinalRule(rc)
@@ -253,7 +259,10 @@ func (h *Handler) Process(ctx context.Context, link *transport.Link, dialer inte
 	ob.Name = "freedom"
 	ob.CanSpliceCopy = 1
 	inbound := session.InboundFromContext(ctx)
-	defaultRule := getDefaultFinalRule(inbound)
+	var defaultRule *FinalRule
+	if !h.usesDialerProxy { // freedom is not the final outbound, final rules do not apply (and the domain is not resolved)
+		defaultRule = getDefaultFinalRule(inbound)
+	}
 
 	destination := ob.Target
 	origTargetAddr := ob.OriginalTarget.Address
@@ -342,15 +351,11 @@ func (h *Handler) Process(ctx context.Context, link *transport.Link, dialer inte
 		return h.blackhole(ctx, input, output, blockedRule, blockedDest)
 	}
 	if destination.Address.Family().IsDomain() && (defaultRule != nil || len(h.finalRules) > 0) {
-		if h.usesDialerProxy {
-			errors.LogInfo(ctx, "skipping final rule check for proxied remote endpoint, original target: ", destination)
-		} else {
-			// pre-check may fail or dialer may select another IP
-			remoteDest := net.DestinationFromAddr(conn.RemoteAddr())
-			if rule := h.matchFinalRule(remoteDest.Network, remoteDest.Address, remoteDest.Port, defaultRule); rule != nil && rule.action == RuleAction_Block {
-				conn.Close()
-				return h.blackhole(ctx, input, output, rule, &remoteDest)
-			}
+		// pre-check may fail or dialer may select another IP
+		remoteDest := net.DestinationFromAddr(conn.RemoteAddr())
+		if rule := h.matchFinalRule(remoteDest.Network, remoteDest.Address, remoteDest.Port, defaultRule); rule != nil && rule.action == RuleAction_Block {
+			conn.Close()
+			return h.blackhole(ctx, input, output, rule, &remoteDest)
 		}
 	}
 

proxy/tun/tun_windows.go

@@ -3,14 +3,14 @@
 package tun
 
 import (
+	"context"
 	"crypto/md5"
 	"encoding/binary"
 	go_errors "errors"
 	"net"
 	"net/netip"
-	"sort"
-	"strings"
 	"sync"
+	"time"
 	"unsafe"
 
 	"github.com/xtls/xray-core/common/errors"
@@ -31,13 +31,14 @@ func procyield(cycles uint32)
 type WindowsTun struct {
 	sync.RWMutex
 
-	options        *Config
-	adapter        *wintun.Adapter
-	session        wintun.Session
-	readWait       windows.Handle
-	luid           winipcfg.LUID
-	changeCallback winipcfg.ChangeCallback
-	closed         bool
+	options  *Config
+	adapter  *wintun.Adapter
+	session  wintun.Session
+	readWait windows.Handle
+	luid     winipcfg.LUID
+	cbr      winipcfg.ChangeCallback
+	cbi      winipcfg.ChangeCallback
+	closed   bool
 }
 
 // WindowsTun implements Tun
@@ -85,23 +86,37 @@ func open(name, desc string) (*wintun.Adapter, error) {
 	return nil, err
 }
 
-func (t *WindowsTun) Start() error {
-	var has4, has6 bool
-	allowedIPs := make([]netip.Prefix, 0, len(t.options.AutoSystemRoutingTable))
-	for _, route := range t.options.AutoSystemRoutingTable {
-		allowedIPs = append(allowedIPs, netip.MustParsePrefix(route))
+func (t *WindowsTun) Start() (err error) {
+	var address4, address6 bool
+	addresses := make([]netip.Prefix, 0, len(t.options.Gateway))
+	for _, cidr := range t.options.Gateway {
+		prefix := netip.MustParsePrefix(cidr)
+		if prefix.Addr().Is4() {
+			address4 = true
+		} else {
+			address6 = true
+		}
+		addresses = append(addresses, prefix)
 	}
+
+	dns := make([]netip.Addr, 0, len(t.options.DNS))
+	for _, ip := range t.options.DNS {
+		dns = append(dns, netip.MustParseAddr(ip))
+	}
+
+	var route4, route6 bool
 	routesMap := make(map[winipcfg.RouteData]struct{})
-	for _, ip := range allowedIPs {
+	for _, cidr := range t.options.AutoSystemRoutingTable {
+		prefix := netip.MustParsePrefix(cidr)
 		route := winipcfg.RouteData{
-			Destination: ip.Masked(),
+			Destination: prefix.Masked(),
 			Metric:      0,
 		}
-		if ip.Addr().Is4() {
-			has4 = true
+		if prefix.Addr().Is4() {
+			route4 = true
 			route.NextHop = netip.IPv4Unspecified()
 		} else {
-			has6 = true
+			route6 = true
 			route.NextHop = netip.IPv6Unspecified()
 		}
 		routesMap[route] = struct{}{}
@@ -111,24 +126,40 @@ func (t *WindowsTun) Start() error {
 		r := route
 		routesData = append(routesData, &r)
 	}
-	err := t.luid.SetRoutes(routesData)
-	if err != nil {
-		return errors.New("unable to set routes").Base(err)
-	}
 
-	if len(t.options.Gateway) > 0 {
-		addresses := make([]netip.Prefix, 0, len(t.options.Gateway))
-		for _, address := range t.options.Gateway {
-			addresses = append(addresses, netip.MustParsePrefix(address))
-		}
-		err := t.luid.SetIPAddresses(addresses)
-		if err != nil {
-			return errors.New("unable to set ips").Base(err)
+	var retryTimes int
+	var firstErr error
+startOver:
+	if retryTimes > 0 {
+		if retryTimes > 15 {
+			return windows.ERROR_NOT_FOUND
 		}
+		errors.LogErrorInner(context.Background(), firstErr, "Interface configuration failed, retrying attempt ", retryTimes, "/15")
+		time.Sleep(time.Second)
 	}
-
-	if has4 {
-		ipif, err := t.luid.IPInterface(windows.AF_INET)
+	retryTimes++
+	for _, family := range []winipcfg.AddressFamily{windows.AF_INET, windows.AF_INET6} {
+		if family == windows.AF_INET && route4 || family == windows.AF_INET6 && route6 {
+			err = t.luid.SetRoutesForFamily(family, routesData)
+			if err != nil {
+				firstErr = errors.New("unable to set routes").Base(err)
+				if err == windows.ERROR_NOT_FOUND {
+					goto startOver
+				}
+				return firstErr
+			}
+		}
+		if family == windows.AF_INET && address4 || family == windows.AF_INET6 && address6 {
+			err = t.luid.SetIPAddressesForFamily(family, addresses)
+			if err != nil {
+				firstErr = errors.New("unable to set ips").Base(err)
+				if err == windows.ERROR_NOT_FOUND {
+					goto startOver
+				}
+				return firstErr
+			}
+		}
+		ipif, err := t.luid.IPInterface(family)
 		if err != nil {
 			return err
 		}
@@ -136,56 +167,45 @@ func (t *WindowsTun) Start() error {
 		ipif.DadTransmits = 0
 		ipif.ManagedAddressConfigurationSupported = false
 		ipif.OtherStatefulConfigurationSupported = false
-		ipif.NLMTU = t.options.MTU
-		ipif.UseAutomaticMetric = false
-		ipif.Metric = 0
+		if family == windows.AF_INET && (address4 || route4) || family == windows.AF_INET6 && (address6 || route6) {
+			ipif.NLMTU = t.options.MTU
+		}
+		if family == windows.AF_INET && route4 || family == windows.AF_INET6 && route6 {
+			ipif.UseAutomaticMetric = false
+			ipif.Metric = 0
+		}
 		err = ipif.Set()
 		if err != nil {
-			return err
+			firstErr = errors.New("unable to set metric and MTU").Base(err)
+			if err == windows.ERROR_NOT_FOUND {
+				goto startOver
+			}
+			return firstErr
 		}
-	}
-	if has6 {
-		ipif, err := t.luid.IPInterface(windows.AF_INET6)
+		err = t.luid.SetDNS(family, dns, nil)
 		if err != nil {
-			return err
-		}
-		ipif.RouterDiscoveryBehavior = winipcfg.RouterDiscoveryDisabled
-		ipif.DadTransmits = 0
-		ipif.ManagedAddressConfigurationSupported = false
-		ipif.OtherStatefulConfigurationSupported = false
-		ipif.NLMTU = t.options.MTU
-		ipif.UseAutomaticMetric = false
-		ipif.Metric = 0
-		err = ipif.Set()
-		if err != nil {
-			return err
-		}
-	}
-
-	if len(t.options.DNS) > 0 {
-		dns := make([]netip.Addr, 0, len(t.options.DNS))
-		for _, ip := range t.options.DNS {
-			dns = append(dns, netip.MustParseAddr(ip))
-		}
-		err := t.luid.SetDNS(windows.AF_INET, dns, nil)
-		if err != nil {
-			return err
-		}
-		err = t.luid.SetDNS(windows.AF_INET6, dns, nil)
-		if err != nil {
-			return err
+			firstErr = errors.New("unable to set DNS").Base(err)
+			if err == windows.ERROR_NOT_FOUND {
+				goto startOver
+			}
+			return firstErr
 		}
 	}
 
 	if updater != nil {
-		t.changeCallback, err = winipcfg.RegisterInterfaceChangeCallback(func(notificationType winipcfg.MibNotificationType, iface *winipcfg.MibIPInterfaceRow) {
+		t.cbr, err = winipcfg.RegisterRouteChangeCallback(func(notificationType winipcfg.MibNotificationType, route *winipcfg.MibIPforwardRow2) {
+			updater.Update()
+		})
+		if err != nil {
+			return err
+		}
+		t.cbi, err = winipcfg.RegisterInterfaceChangeCallback(func(notificationType winipcfg.MibNotificationType, iface *winipcfg.MibIPInterfaceRow) {
 			updater.Update()
 		})
 		if err != nil {
 			return err
 		}
 	}
-
 	return nil
 }
 
@@ -197,12 +217,26 @@ func (t *WindowsTun) Close() error {
 	}
 	t.closed = true
 
-	if t.changeCallback != nil {
-		t.changeCallback.Unregister()
+	if t.cbr != nil {
+		t.cbr.Unregister()
+	}
+	if t.cbi != nil {
+		t.cbi.Unregister()
+	}
+	if t.luid != 0 {
+		t.luid.FlushRoutes(windows.AF_INET)
+		t.luid.FlushIPAddresses(windows.AF_INET)
+		t.luid.FlushDNS(windows.AF_INET)
+		t.luid.FlushRoutes(windows.AF_INET6)
+		t.luid.FlushIPAddresses(windows.AF_INET6)
+		t.luid.FlushDNS(windows.AF_INET6)
+	}
+	if t.session != (wintun.Session{}) {
+		t.session.End()
+	}
+	if t.adapter != nil {
+		t.adapter.Close()
 	}
-	t.session.End()
-	_ = t.adapter.Close()
-
 	return nil
 }
 
@@ -311,75 +345,49 @@ func setinterface(network, address string, fd uintptr, iface *net.Interface) err
 }
 
 func findOutboundInterface(tunIndex int, fixedName string) (*net.Interface, error) {
-	interfaces, err := net.Interfaces()
+	if fixedName != "" {
+		return net.InterfaceByName(fixedName)
+	}
+
+	r, err := winipcfg.GetIPForwardTable2(windows.AF_UNSPEC)
 	if err != nil {
 		return nil, err
 	}
+	lowestMetric := ^uint32(0)
+	index := uint32(0)
+	lowestMetricWifi := ^uint32(0)
+	indexWifi := uint32(0)
+	for i := range r {
+		if r[i].DestinationPrefix.PrefixLength != 0 || r[i].InterfaceIndex == uint32(tunIndex) {
+			continue
+		}
+		ifrow, err := r[i].InterfaceLUID.Interface()
+		if err != nil || ifrow.OperStatus != winipcfg.IfOperStatusUp {
+			continue
+		}
 
-	if fixedName != "" {
-		for _, iface := range interfaces {
-			if iface.Index != tunIndex && iface.Name == fixedName {
-				return &iface, nil
+		iface, err := r[i].InterfaceLUID.IPInterface(windows.AF_INET)
+		if err != nil {
+			iface, err = r[i].InterfaceLUID.IPInterface(windows.AF_INET6)
+			if err != nil {
+				continue
 			}
 		}
-		return nil, nil
-	}
 
-	var candidates []struct {
-		index int
-		score int
+		if ifrow.Type == windows.IF_TYPE_IEEE80211 {
+			if r[i].Metric+iface.Metric < lowestMetricWifi {
+				lowestMetricWifi = r[i].Metric + iface.Metric
+				indexWifi = r[i].InterfaceIndex
+			}
+			continue
+		}
+		if r[i].Metric+iface.Metric < lowestMetric {
+			lowestMetric = r[i].Metric + iface.Metric
+			index = r[i].InterfaceIndex
+		}
 	}
-	for i, iface := range interfaces {
-		if iface.Index == tunIndex {
-			continue
-		}
-		if strings.Contains(iface.Name, "vEthernet") {
-			continue
-		}
-		if iface.Flags&net.FlagUp == 0 {
-			continue
-		}
-		if iface.Flags&net.FlagLoopback != 0 {
-			continue
-		}
-		addrs, err := iface.Addrs()
-		if err != nil || len(addrs) == 0 {
-			continue
-		}
-		candidates = append(candidates, struct {
-			index int
-			score int
-		}{i, scoreWindowsInterface(&iface, addrs)})
+	if indexWifi != 0 {
+		index = indexWifi
 	}
-
-	sort.Slice(candidates, func(i, j int) bool {
-		if candidates[i].score != candidates[j].score {
-			return candidates[i].score > candidates[j].score
-		}
-		return interfaces[candidates[i].index].Name < interfaces[candidates[j].index].Name
-	})
-	if len(candidates) == 0 {
-		return nil, nil
-	}
-
-	iface := interfaces[candidates[0].index]
-	return &iface, nil
-}
-
-func scoreWindowsInterface(iface *net.Interface, addrs []net.Addr) int {
-	score := 0
-
-	name := strings.ToLower(iface.Name)
-	if strings.Contains(name, "wlan") || strings.Contains(name, "wi-fi") {
-		score += 2
-	}
-
-	for _, addr := range addrs {
-		if strings.HasPrefix(addr.String(), "192.168.") {
-			score++
-			break
-		}
-	}
-
-	return score
+	return net.InterfaceByIndex(int(index))
 }