Add fakeip support

adapter/experimental.go

@@ -13,6 +13,7 @@ type ClashServer interface {
 	PreStarter
 	Mode() string
 	StoreSelected() bool
+	StoreFakeIP() bool
 	CacheFile() ClashCacheFile
 	HistoryStorage() *urltest.HistoryStorage
 	RoutedConnection(ctx context.Context, conn net.Conn, metadata InboundContext, matchedRule Rule) (net.Conn, Tracker)
@@ -22,6 +23,7 @@ type ClashServer interface {
 type ClashCacheFile interface {
 	LoadSelected(group string) string
 	StoreSelected(group string, selected string) error
+	FakeIPStorage
 }
 
 type Tracker interface {

adapter/fakeip.go

@@ -0,0 +1,23 @@
+package adapter
+
+import (
+	"net/netip"
+
+	"github.com/sagernet/sing-dns"
+)
+
+type FakeIPStore interface {
+	Service
+	Contains(address netip.Addr) bool
+	Create(domain string, strategy dns.DomainStrategy) (netip.Addr, error)
+	Lookup(address netip.Addr) (string, bool)
+	Reset() error
+}
+
+type FakeIPStorage interface {
+	FakeIPMetadata() *FakeIPMetadata
+	FakeIPSaveMetadata(metadata *FakeIPMetadata) error
+	FakeIPStore(address netip.Addr, domain string) error
+	FakeIPLoad(address netip.Addr) (string, bool)
+	FakeIPReset() error
+}

adapter/fakeip_metadata.go

@@ -0,0 +1,50 @@
+package adapter
+
+import (
+	"bytes"
+	"encoding"
+	"encoding/binary"
+	"io"
+	"net/netip"
+
+	"github.com/sagernet/sing/common"
+)
+
+type FakeIPMetadata struct {
+	Inet4Range   netip.Prefix
+	Inet6Range   netip.Prefix
+	Inet4Current netip.Addr
+	Inet6Current netip.Addr
+}
+
+func (m *FakeIPMetadata) MarshalBinary() (data []byte, err error) {
+	var buffer bytes.Buffer
+	for _, marshaler := range []encoding.BinaryMarshaler{m.Inet4Range, m.Inet6Range, m.Inet4Current, m.Inet6Current} {
+		data, err = marshaler.MarshalBinary()
+		if err != nil {
+			return
+		}
+		common.Must(binary.Write(&buffer, binary.BigEndian, uint16(len(data))))
+		buffer.Write(data)
+	}
+	data = buffer.Bytes()
+	return
+}
+
+func (m *FakeIPMetadata) UnmarshalBinary(data []byte) error {
+	reader := bytes.NewReader(data)
+	for _, unmarshaler := range []encoding.BinaryUnmarshaler{&m.Inet4Range, &m.Inet6Range, &m.Inet4Current, &m.Inet6Current} {
+		var length uint16
+		common.Must(binary.Read(reader, binary.BigEndian, &length))
+		element := make([]byte, length)
+		_, err := io.ReadFull(reader, element)
+		if err != nil {
+			return err
+		}
+		err = unmarshaler.UnmarshalBinary(element)
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}

adapter/router.go

@@ -21,6 +21,8 @@ type Router interface {
 	Outbound(tag string) (Outbound, bool)
 	DefaultOutbound(network string) Outbound
 
+	FakeIPStore() FakeIPStore
+
 	RouteConnection(ctx context.Context, conn net.Conn, metadata InboundContext) error
 	RoutePacketConnection(ctx context.Context, conn N.PacketConn, metadata InboundContext) error
 	RouteIPConnection(ctx context.Context, conn tun.RouteContext, metadata InboundContext) tun.RouteAction