chore: support longest-prefix matches in local interface finding

component/iface/iface.go

@@ -7,6 +7,8 @@ import (
 	"time"
 
 	"github.com/metacubex/mihomo/common/singledo"
+
+	"github.com/metacubex/bart"
 )
 
 type Interface struct {
@@ -23,16 +25,23 @@ var (
 	ErrAddrNotFound  = errors.New("addr not found")
 )
 
-var interfaces = singledo.NewSingle[map[string]*Interface](time.Second * 20)
+type ifaceCache struct {
+	ifMap   map[string]*Interface
+	ifTable bart.Table[*Interface]
+}
 
-func Interfaces() (map[string]*Interface, error) {
+var caches = singledo.NewSingle[*ifaceCache](time.Second * 20)
-	value, err, _ := interfaces.Do(func() (map[string]*Interface, error) {
+
+func getCache() (*ifaceCache, error) {
+	value, err, _ := caches.Do(func() (*ifaceCache, error) {
 		ifaces, err := net.Interfaces()
 		if err != nil {
 			return nil, err
 		}
 
-		r := map[string]*Interface{}
+		cache := &ifaceCache{
+			ifMap: make(map[string]*Interface),
+		}
 
 		for _, iface := range ifaces {
 			addrs, err := iface.Addrs()
@@ -61,7 +70,7 @@ func Interfaces() (map[string]*Interface, error) {
 				}
 			}
 
-			r[iface.Name] = &Interface{
+			ifaceObj := &Interface{
 				Index:        iface.Index,
 				MTU:          iface.MTU,
 				Name:         iface.Name,
@@ -69,13 +78,26 @@ func Interfaces() (map[string]*Interface, error) {
 				Flags:        iface.Flags,
 				Addresses:    ipNets,
 			}
+			cache.ifMap[iface.Name] = ifaceObj
+
+			for _, prefix := range ipNets {
+				cache.ifTable.Insert(prefix, ifaceObj)
+			}
 		}
 
-		return r, nil
+		return cache, nil
 	})
 	return value, err
 }
 
+func Interfaces() (map[string]*Interface, error) {
+	cache, err := getCache()
+	if err != nil {
+		return nil, err
+	}
+	return cache.ifMap, nil
+}
+
 func ResolveInterface(name string) (*Interface, error) {
 	ifaces, err := Interfaces()
 	if err != nil {
@@ -90,23 +112,29 @@ func ResolveInterface(name string) (*Interface, error) {
 	return iface, nil
 }
 
-func IsLocalIp(ip netip.Addr) (bool, error) {
+func ResolveInterfaceByAddr(addr netip.Addr) (*Interface, error) {
-	ifaces, err := Interfaces()
+	cache, err := getCache()
+	if err != nil {
+		return nil, err
+	}
+	iface, ok := cache.ifTable.Lookup(addr)
+	if !ok {
+		return nil, ErrIfaceNotFound
+	}
+
+	return iface, nil
+}
+
+func IsLocalIp(addr netip.Addr) (bool, error) {
+	cache, err := getCache()
 	if err != nil {
 		return false, err
 	}
-	for _, iface := range ifaces {
+	return cache.ifTable.Contains(addr), nil
-		for _, addr := range iface.Addresses {
-			if addr.Contains(ip) {
-				return true, nil
-			}
-		}
-	}
-	return false, nil
 }
 
 func FlushCache() {
-	interfaces.Reset()
+	caches.Reset()
 }
 
 func (iface *Interface) PickIPv4Addr(destination netip.Addr) (netip.Prefix, error) {

go.mod

@@ -18,6 +18,7 @@ require (
 	github.com/lunixbochs/struc v0.0.0-20200707160740-784aaebc1d40
 	github.com/mdlayher/netlink v1.7.2
 	github.com/metacubex/amneziawg-go v0.0.0-20240922133038-fdf3a4d5a4ab
+	github.com/metacubex/bart v0.19.0
 	github.com/metacubex/bbolt v0.0.0-20240822011022-aed6d4850399
 	github.com/metacubex/chacha v0.1.1
 	github.com/metacubex/gopacket v1.1.20-0.20230608035415-7e2f98a3e759

go.sum

@@ -97,6 +97,8 @@ github.com/mdlayher/socket v0.4.1 h1:eM9y2/jlbs1M615oshPQOHZzj6R6wMT7bX5NPiQvn2U
 github.com/mdlayher/socket v0.4.1/go.mod h1:cAqeGjoufqdxWkD7DkpyS+wcefOtmu5OQ8KuoJGIReA=
 github.com/metacubex/amneziawg-go v0.0.0-20240922133038-fdf3a4d5a4ab h1:Chbw+/31UC14YFNr78pESt5Vowlc62zziw05JCUqoL4=
 github.com/metacubex/amneziawg-go v0.0.0-20240922133038-fdf3a4d5a4ab/go.mod h1:xVKK8jC5Sd3hfh7WjmCq+HorehIbrBijaUWmcuKjPcI=
+github.com/metacubex/bart v0.19.0 h1:XQ9AJeI+WO+phRPkUOoflAFwlqDJnm5BPQpixciJQBY=
+github.com/metacubex/bart v0.19.0/go.mod h1:DCcyfP4MC+Zy7sLK7XeGuMw+P5K9mIRsYOBgiE8icsI=
 github.com/metacubex/bbolt v0.0.0-20240822011022-aed6d4850399 h1:oBowHVKZycNtAFbZ6avaCSZJYeme2Nrj+4RpV2cNJig=
 github.com/metacubex/bbolt v0.0.0-20240822011022-aed6d4850399/go.mod h1:4xcieuIK+M4bGQmQYZVqEaIYqjS1ahO4kXG7EmDgEro=
 github.com/metacubex/chacha v0.1.1 h1:OHIv11Nd9CISAIzegpjfupIoZp9DYm6uQw41RxvmU/c=

listener/sing_tun/iface.go

@@ -1,7 +1,6 @@
 package sing_tun
 
 import (
-	"errors"
 	"net"
 	"net/netip"
 
@@ -16,7 +15,8 @@ var DefaultInterfaceFinder control.InterfaceFinder = (*defaultInterfaceFinder)(n
 
 func (f *defaultInterfaceFinder) Update() error {
 	iface.FlushCache()
-	return nil
+	_, err := iface.Interfaces()
+	return err
 }
 
 func (f *defaultInterfaceFinder) Interfaces() []control.Interface {
@@ -32,27 +32,19 @@ func (f *defaultInterfaceFinder) Interfaces() []control.Interface {
 	return interfaces
 }
 
-var errNoSuchInterface = errors.New("no such network interface")
-
 func (f *defaultInterfaceFinder) ByName(name string) (*control.Interface, error) {
-	ifaces, err := iface.Interfaces()
+	netInterface, err := iface.ResolveInterface(name)
-	if err != nil {
-		return nil, err
-	}
-	for _, netInterface := range ifaces {
-		if netInterface.Name == name {
-			return (*control.Interface)(netInterface), nil
-		}
-	}
-	_, err = net.InterfaceByName(name)
 	if err == nil {
+		return (*control.Interface)(netInterface), nil
+	}
+	if _, err := net.InterfaceByName(name); err == nil {
 		err = f.Update()
 		if err != nil {
 			return nil, err
 		}
 		return f.ByName(name)
 	}
-	return nil, errNoSuchInterface
+	return nil, err
 }
 
 func (f *defaultInterfaceFinder) ByIndex(index int) (*control.Interface, error) {
@@ -73,20 +65,13 @@ func (f *defaultInterfaceFinder) ByIndex(index int) (*control.Interface, error)
 		}
 		return f.ByIndex(index)
 	}
-	return nil, errNoSuchInterface
+	return nil, iface.ErrIfaceNotFound
 }
 
 func (f *defaultInterfaceFinder) ByAddr(addr netip.Addr) (*control.Interface, error) {
-	ifaces, err := iface.Interfaces()
+	netInterface, err := iface.ResolveInterfaceByAddr(addr)
 	if err != nil {
 		return nil, err
 	}
-	for _, netInterface := range ifaces {
+	return (*control.Interface)(netInterface), nil
-		for _, prefix := range netInterface.Addresses {
-			if prefix.Contains(addr) {
-				return (*control.Interface)(netInterface), nil
-			}
-		}
-	}
-	return nil, errNoSuchInterface
 }