Only reseponse fakeip on dns exchanging

SagerNet · Nov 5, 2023 · ef3837c · ef3837c
1 parent 556c74e
commit ef3837c
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Showing 3 changed files with 21 additions and 11 deletions.
diff --git a/adapter/inbound.go b/adapter/inbound.go
@@ -46,7 +46,6 @@ type InboundContext struct {
 	SourceGeoIPCode      string
 	GeoIPCode            string
 	ProcessInfo          *process.Info
-	FakeIP               bool
 
 	// dns cache
 

diff --git a/route/router.go b/route/router.go
@@ -625,7 +625,6 @@ func (r *Router) RouteConnection(ctx context.Context, conn net.Conn, metadata ad
 			Fqdn: domain,
 			Port: metadata.Destination.Port,
 		}
-		metadata.FakeIP = true
 		r.logger.DebugContext(ctx, "found fakeip domain: ", domain)
 	}
 
@@ -703,6 +702,7 @@ func (r *Router) RouteConnection(ctx context.Context, conn net.Conn, metadata ad
 }
 
 func (r *Router) RoutePacketConnection(ctx context.Context, conn N.PacketConn, metadata adapter.InboundContext) error {
+	var rewriteDestination bool
 	if metadata.InboundDetour != "" {
 		if metadata.LastInbound == metadata.InboundDetour {
 			return E.New("routing loop on detour: ", metadata.InboundDetour)
@@ -740,7 +740,7 @@ func (r *Router) RoutePacketConnection(ctx context.Context, conn N.PacketConn, m
 			Fqdn: domain,
 			Port: metadata.Destination.Port,
 		}
-		metadata.FakeIP = true
+		rewriteDestination = true
 		r.logger.DebugContext(ctx, "found fakeip domain: ", domain)
 	}
 
@@ -766,6 +766,7 @@ func (r *Router) RoutePacketConnection(ctx context.Context, conn N.PacketConn, m
 				metadata.Protocol = sniffMetadata.Protocol
 				metadata.Domain = sniffMetadata.Domain
 				if metadata.InboundOptions.SniffOverrideDestination && M.IsDomainName(metadata.Domain) {
+					rewriteDestination = true
 					metadata.Destination = M.Socksaddr{
 						Fqdn: metadata.Domain,
 						Port: metadata.Destination.Port,
@@ -817,7 +818,7 @@ func (r *Router) RoutePacketConnection(ctx context.Context, conn N.PacketConn, m
 			conn = statsService.RoutedPacketConnection(metadata.Inbound, detour.Tag(), metadata.User, conn)
 		}
 	}
-	if metadata.FakeIP {
+	if rewriteDestination {
 		conn = bufio.NewNATPacketConn(bufio.NewNetPacketConn(conn), metadata.OriginDestination, metadata.Destination)
 	}
 	return detour.NewPacketConnection(ctx, conn, metadata)

diff --git a/route/router_dns.go b/route/router_dns.go
@@ -37,7 +37,7 @@ func (m *DNSReverseMapping) Query(address netip.Addr) (string, bool) {
 	return domain, loaded
 }
 
-func (r *Router) matchDNS(ctx context.Context) (context.Context, dns.Transport, dns.DomainStrategy) {
+func (r *Router) matchDNS(ctx context.Context, useFakeIP bool) (context.Context, dns.Transport, dns.DomainStrategy) {
 	metadata := adapter.ContextFrom(ctx)
 	if metadata == nil {
 		panic("no context")
@@ -50,7 +50,7 @@ func (r *Router) matchDNS(ctx context.Context) (context.Context, dns.Transport,
 				r.dnsLogger.ErrorContext(ctx, "transport not found: ", detour)
 				continue
 			}
-			if _, isFakeIP := transport.(adapter.FakeIPTransport); isFakeIP && metadata.FakeIP {
+			if _, isFakeIP := transport.(adapter.FakeIPTransport); isFakeIP && !useFakeIP {
 				continue
 			}
 			r.dnsLogger.DebugContext(ctx, "match[", i, "] ", rule.String(), " => ", detour)
@@ -67,10 +67,20 @@ func (r *Router) matchDNS(ctx context.Context) (context.Context, dns.Transport,
 			}
 		}
 	}
-	if domainStrategy, dsLoaded := r.transportDomainStrategy[r.defaultTransport]; dsLoaded {
-		return ctx, r.defaultTransport, domainStrategy
+	transport := r.defaultTransport
+	if _, isFakeIP := transport.(adapter.FakeIPTransport); isFakeIP && !useFakeIP {
+		for _, t := range r.transports {
+			if _, isFakeIP := t.(adapter.FakeIPTransport); isFakeIP {
+				continue
+			}
+			transport = t
+			break
+		}
+	}
+	if domainStrategy, dsLoaded := r.transportDomainStrategy[transport]; dsLoaded {
+		return ctx, transport, domainStrategy
 	} else {
-		return ctx, r.defaultTransport, r.defaultDomainStrategy
+		return ctx, transport, r.defaultDomainStrategy
 	}
 }
 
@@ -96,7 +106,7 @@ func (r *Router) Exchange(ctx context.Context, message *mDNS.Msg) (*mDNS.Msg, er
 			}
 			metadata.Domain = fqdnToDomain(message.Question[0].Name)
 		}
-		ctx, transport, strategy := r.matchDNS(ctx)
+		ctx, transport, strategy := r.matchDNS(ctx, true)
 		ctx, cancel := context.WithTimeout(ctx, C.DNSTimeout)
 		defer cancel()
 		response, err = r.dnsClient.Exchange(ctx, transport, message, strategy)
@@ -124,7 +134,7 @@ func (r *Router) Lookup(ctx context.Context, domain string, strategy dns.DomainS
 	r.dnsLogger.DebugContext(ctx, "lookup domain ", domain)
 	ctx, metadata := adapter.AppendContext(ctx)
 	metadata.Domain = domain
-	ctx, transport, transportStrategy := r.matchDNS(ctx)
+	ctx, transport, transportStrategy := r.matchDNS(ctx, false)
 	if strategy == dns.DomainStrategyAsIS {
 		strategy = transportStrategy
 	}