chore: handle two interfaces have the same prefix but different address

wwqgtxx · wwqgtxx · commit 9e3bf14b1aa1 · 2025-05-24T11:32:36.000+08:00
diff --git a/component/iface/iface.go b/component/iface/iface.go
@@ -26,8 +26,9 @@ var (
 )
 
 type ifaceCache struct {
-	ifMap   map[string]*Interface
-	ifTable bart.Table[*Interface]
+	ifMapByName map[string]*Interface
+	ifMapByAddr map[netip.Addr]*Interface
+	ifTable     bart.Table[*Interface]
 }
 
 var caches = singledo.NewSingle[*ifaceCache](time.Second * 20)
@@ -40,7 +41,8 @@ func getCache() (*ifaceCache, error) {
 		}
 
 		cache := &ifaceCache{
-			ifMap: make(map[string]*Interface),
+			ifMapByName: make(map[string]*Interface),
+			ifMapByAddr: make(map[netip.Addr]*Interface),
 		}
 
 		for _, iface := range ifaces {
@@ -78,12 +80,13 @@ func getCache() (*ifaceCache, error) {
 				Flags:        iface.Flags,
 				Addresses:    ipNets,
 			}
-			cache.ifMap[iface.Name] = ifaceObj
+			cache.ifMapByName[iface.Name] = ifaceObj
 
 			if iface.Flags&net.FlagUp == 0 {
 				continue // interface down
 			}
 			for _, prefix := range ipNets {
+				cache.ifMapByAddr[prefix.Addr()] = ifaceObj
 				cache.ifTable.Insert(prefix, ifaceObj)
 			}
 		}
@@ -98,7 +101,7 @@ func Interfaces() (map[string]*Interface, error) {
 	if err != nil {
 		return nil, err
 	}
-	return cache.ifMap, nil
+	return cache.ifMapByName, nil
 }
 
 func ResolveInterface(name string) (*Interface, error) {
@@ -120,6 +123,11 @@ func ResolveInterfaceByAddr(addr netip.Addr) (*Interface, error) {
 	if err != nil {
 		return nil, err
 	}
+	// maybe two interfaces have the same prefix but different address
+	// so direct check address equal before do a route lookup (longest prefix match)
+	if iface, ok := cache.ifMapByAddr[addr]; ok {
+		return iface, nil
+	}
 	iface, ok := cache.ifTable.Lookup(addr)
 	if !ok {
 		return nil, ErrIfaceNotFound
@@ -133,7 +141,8 @@ func IsLocalIp(addr netip.Addr) (bool, error) {
 	if err != nil {
 		return false, err
 	}
-	return cache.ifTable.Contains(addr), nil
+	_, ok := cache.ifMapByAddr[addr]
+	return ok, nil
 }
 
 func FlushCache() {
diff --git a/go.mod b/go.mod
@@ -25,7 +25,7 @@ require (
 	github.com/metacubex/gopacket v1.1.20-0.20230608035415-7e2f98a3e759
 	github.com/metacubex/quic-go v0.52.1-0.20250522021943-aef454b9e639
 	github.com/metacubex/randv2 v0.2.0
-	github.com/metacubex/sing v0.5.3-0.20250504031621-1f99e54c15b7
+	github.com/metacubex/sing v0.5.3
 	github.com/metacubex/sing-mux v0.3.2
 	github.com/metacubex/sing-quic v0.0.0-20250523120938-f1a248e5ec7f
 	github.com/metacubex/sing-shadowsocks v0.2.9
diff --git a/go.sum b/go.sum
@@ -116,8 +116,8 @@ github.com/metacubex/quic-go v0.52.1-0.20250522021943-aef454b9e639/go.mod h1:Kc6
 github.com/metacubex/randv2 v0.2.0 h1:uP38uBvV2SxYfLj53kuvAjbND4RUDfFJjwr4UigMiLs=
 github.com/metacubex/randv2 v0.2.0/go.mod h1:kFi2SzrQ5WuneuoLLCMkABtiBu6VRrMrWFqSPyj2cxY=
 github.com/metacubex/sing v0.5.2/go.mod h1:ypf0mjwlZm0sKdQSY+yQvmsbWa0hNPtkeqyRMGgoN+w=
-github.com/metacubex/sing v0.5.3-0.20250504031621-1f99e54c15b7 h1:m4nSxvw46JEgxMzzmnXams+ebwabcry4Ydep/zNiesQ=
-github.com/metacubex/sing v0.5.3-0.20250504031621-1f99e54c15b7/go.mod h1:ypf0mjwlZm0sKdQSY+yQvmsbWa0hNPtkeqyRMGgoN+w=
+github.com/metacubex/sing v0.5.3 h1:QWdN16WFKMk06x4nzkc8SvZ7y2x+TLQrpkPoHs+WSVM=
+github.com/metacubex/sing v0.5.3/go.mod h1:ypf0mjwlZm0sKdQSY+yQvmsbWa0hNPtkeqyRMGgoN+w=
 github.com/metacubex/sing-mux v0.3.2 h1:nJv52pyRivHcaZJKk2JgxpaVvj1GAXG81scSa9N7ncw=
 github.com/metacubex/sing-mux v0.3.2/go.mod h1:3rt1soewn0O6j89GCLmwAQFsq257u0jf2zQSPhTL3Bw=
 github.com/metacubex/sing-quic v0.0.0-20250523120938-f1a248e5ec7f h1:mP3vIm+9hRFI0C0Vl3pE0NESF/L85FDbuB0tGgUii6I=

Original file line number	Diff line number	Diff line change
`@@ -26,8 +26,9 @@ var (`
`26`	`26`	`)`
`27`	`27`
`28`	`28`	`type ifaceCache struct {`
`29`		`- ifMap map[string]*Interface`
`30`		`- ifTable bart.Table[*Interface]`
	`29`	`+ ifMapByName map[string]*Interface`
	`30`	`+ ifMapByAddr map[netip.Addr]*Interface`
	`31`	`+ ifTable bart.Table[*Interface]`
`31`	`32`	`}`
`32`	`33`
`33`	`34`	`var caches = singledo.NewSingle[ifaceCache](time.Second 20)`
`@@ -40,7 +41,8 @@ func getCache() (*ifaceCache, error) {`
`40`	`41`	`}`
`41`	`42`
`42`	`43`	`cache := &ifaceCache{`
`43`		`- ifMap: make(map[string]*Interface),`
	`44`	`+ ifMapByName: make(map[string]*Interface),`
	`45`	`+ ifMapByAddr: make(map[netip.Addr]*Interface),`
`44`	`46`	`}`
`45`	`47`
`46`	`48`	`for _, iface := range ifaces {`
`@@ -78,12 +80,13 @@ func getCache() (*ifaceCache, error) {`
`78`	`80`	`Flags: iface.Flags,`
`79`	`81`	`Addresses: ipNets,`
`80`	`82`	`}`
`81`		`- cache.ifMap[iface.Name] = ifaceObj`
	`83`	`+ cache.ifMapByName[iface.Name] = ifaceObj`
`82`	`84`
`83`	`85`	`if iface.Flags&net.FlagUp == 0 {`
`84`	`86`	`continue // interface down`
`85`	`87`	`}`
`86`	`88`	`for _, prefix := range ipNets {`
	`89`	`+ cache.ifMapByAddr[prefix.Addr()] = ifaceObj`
`87`	`90`	`cache.ifTable.Insert(prefix, ifaceObj)`
`88`	`91`	`}`
`89`	`92`	`}`
`@@ -98,7 +101,7 @@ func Interfaces() (map[string]*Interface, error) {`
`98`	`101`	`if err != nil {`
`99`	`102`	`return nil, err`
`100`	`103`	`}`
`101`		`- return cache.ifMap, nil`
	`104`	`+ return cache.ifMapByName, nil`
`102`	`105`	`}`
`103`	`106`
`104`	`107`	`func ResolveInterface(name string) (*Interface, error) {`
`@@ -120,6 +123,11 @@ func ResolveInterfaceByAddr(addr netip.Addr) (*Interface, error) {`
`120`	`123`	`if err != nil {`
`121`	`124`	`return nil, err`
`122`	`125`	`}`
	`126`	`+ // maybe two interfaces have the same prefix but different address`
	`127`	`+ // so direct check address equal before do a route lookup (longest prefix match)`
	`128`	`+ if iface, ok := cache.ifMapByAddr[addr]; ok {`
	`129`	`+ return iface, nil`
	`130`	`+ }`
`123`	`131`	`iface, ok := cache.ifTable.Lookup(addr)`
`124`	`132`	`if !ok {`
`125`	`133`	`return nil, ErrIfaceNotFound`
`@@ -133,7 +141,8 @@ func IsLocalIp(addr netip.Addr) (bool, error) {`
`133`	`141`	`if err != nil {`
`134`	`142`	`return false, err`
`135`	`143`	`}`
`136`		`- return cache.ifTable.Contains(addr), nil`
	`144`	`+ _, ok := cache.ifMapByAddr[addr]`
	`145`	`+ return ok, nil`
`137`	`146`	`}`
`138`	`147`
`139`	`148`	`func FlushCache() {`