Merge commit 'b26a91de4f3294e26a0ad0a970b81a386a41f789' into lua

app/dispatcher/fakednssniffer.go

@@ -23,7 +23,7 @@ func newFakeDNSSniffer(ctx context.Context) (protocolSnifferWithMetadata, error)
 	}
 
 	if fakeDNSEngine == nil {
-		errNotInit := errors.New("FakeDNSEngine is not initialized, but such a sniffer is used").AtError()
+		errNotInit := errors.New("FakeDNSEngine is not initialized, but such a sniffer is used")
 		return protocolSnifferWithMetadata{}, errNotInit
 	}
 	return protocolSnifferWithMetadata{protocolSniffer: func(ctx context.Context, bytes []byte) (SniffResult, error) {

app/dns/config.go

@@ -28,7 +28,7 @@ func toNetIP(addrs []net.Address) ([]net.IP, error) {
 		if addr.Family().IsIP() {
 			ips = append(ips, addr.IP())
 		} else {
-			return nil, errors.New("Failed to convert address", addr, "to Net IP.").AtWarning()
+			return nil, errors.New("Failed to convert address", addr, "to Net IP.")
 		}
 	}
 	return ips, nil

app/dns/dns.go

@@ -225,6 +225,28 @@ func (s *DNS) IsOwnLink(ctx context.Context) bool {
 	return false
 }
 
+// MayUseSystemResolver reports whether any name server configured here could
+// still resolve through the system resolver. That is what happens when no name
+// server is configured at all, and it is also what a name server pointed at
+// "localhost" does. Callers that are about to redirect the system resolver need
+// to know, because a resolution path that reaches it would then loop back to
+// them.
+//
+// Any such server is enough: name servers can be selected per domain, so a
+// single local one makes some query reach the system resolver even when
+// independent upstreams are configured alongside it.
+func (s *DNS) MayUseSystemResolver() bool {
+	if len(s.clients) == 0 {
+		return true
+	}
+	for _, client := range s.clients {
+		if _, isLocal := client.server.(*LocalNameServer); isLocal {
+			return true
+		}
+	}
+	return false
+}
+
 // LookupIP implements dns.Client.
 func (s *DNS) LookupIP(domain string, option dns.IPOption) ([]net.IP, uint32, error) {
 	// Normalize the FQDN form query

app/dns/dns_internal_test.go

@@ -0,0 +1,59 @@
+package dns
+
+import (
+	"context"
+	"testing"
+
+	"github.com/xtls/xray-core/common/net"
+	feature_dns "github.com/xtls/xray-core/features/dns"
+)
+
+// fakeServer stands in for any name server that is not the system resolver.
+type fakeServer struct{}
+
+func (fakeServer) Name() string         { return "fake" }
+func (fakeServer) IsDisableCache() bool { return false }
+func (fakeServer) QueryIP(context.Context, string, feature_dns.IPOption) ([]net.IP, uint32, error) {
+	return nil, 0, nil
+}
+
+// Callers that are about to redirect the system resolver rely on this to tell
+// whether any resolution path could still reach the system resolver, so the
+// mixed shape has to be reported as reachable: a domain-specific rule can
+// select the system resolver even when an independent upstream also exists.
+func TestMayUseSystemResolver(t *testing.T) {
+	tests := []struct {
+		name    string
+		clients []*Client
+		want    bool
+	}{
+		{
+			name: "no clients at all",
+			want: true,
+		},
+		{
+			name:    "only the system resolver",
+			clients: []*Client{{server: NewLocalNameServer()}},
+			want:    true,
+		},
+		{
+			name:    "the system resolver alongside an independent name server",
+			clients: []*Client{{server: fakeServer{}}, {server: NewLocalNameServer()}},
+			want:    true,
+		},
+		{
+			name:    "only independent name servers",
+			clients: []*Client{{server: fakeServer{}}},
+			want:    false,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			server := &DNS{clients: tt.clients}
+			if got := server.MayUseSystemResolver(); got != tt.want {
+				t.Errorf("MayUseSystemResolver() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}

app/dns/dnscommon.go

@@ -188,10 +188,10 @@ func parseResponse(payload []byte) (*IPRecord, error) {
 	var parser dnsmessage.Parser
 	h, err := parser.Start(payload)
 	if err != nil {
-		return nil, errors.New("failed to parse DNS response").Base(err).AtWarning()
+		return nil, errors.New("failed to parse DNS response").Base(err)
 	}
 	if err := parser.SkipAllQuestions(); err != nil {
-		return nil, errors.New("failed to skip questions in DNS response").Base(err).AtWarning()
+		return nil, errors.New("failed to skip questions in DNS response").Base(err)
 	}
 
 	now := time.Now()

app/dns/fakedns/fake.go

@@ -58,7 +58,7 @@ func NewFakeDNSHolder() (*Holder, error) {
 	var err error
 
 	if fkdns, err = NewFakeDNSHolderConfigOnly(nil); err != nil {
-		return nil, errors.New("Unable to create Fake Dns Engine").Base(err).AtError()
+		return nil, errors.New("Unable to create Fake Dns Engine").Base(err)
 	}
 	err = fkdns.initialize(dns.FakeIPv4Pool, 65535)
 	if err != nil {
@@ -80,13 +80,13 @@ func (fkdns *Holder) initialize(ipPoolCidr string, lruSize int) error {
 	var err error
 
 	if _, ipRange, err = net.ParseCIDR(ipPoolCidr); err != nil {
-		return errors.New("Unable to parse CIDR for Fake DNS IP assignment").Base(err).AtError()
+		return errors.New("Unable to parse CIDR for Fake DNS IP assignment").Base(err)
 	}
 
 	ones, bits := ipRange.Mask.Size()
 	rooms := bits - ones
 	if math.Log2(float64(lruSize)) >= float64(rooms) {
-		return errors.New("LRU size is bigger than subnet size").AtError()
+		return errors.New("LRU size is bigger than subnet size")
 	}
 	fkdns.domainToIP = cache.NewLru(lruSize)
 	fkdns.ipRange = ipRange

app/dns/nameserver.go

@@ -85,7 +85,7 @@ func NewServer(ctx context.Context, dest net.Destination, dispatcher routing.Dis
 	if dest.Network == net.Network_UDP { // UDP classic DNS mode
 		return NewClassicNameServer(dest, dispatcher, disableCache, serveStale, serveExpiredTTL, clientIP), nil
 	}
-	return nil, errors.New("No available name server could be created from ", dest).AtWarning()
+	return nil, errors.New("No available name server could be created from ", dest)
 }
 
 // NewClient creates a DNS client managing a name server with client IP, domain rules and expected IPs.
@@ -103,7 +103,7 @@ func NewClient(
 		// Create a new server for each client for now
 		server, err := NewServer(ctx, ns.Address.AsDestination(), dispatcher, disableCache, serveStale, serveExpiredTTL, clientIP)
 		if err != nil {
-			return errors.New("failed to create nameserver").Base(err).AtWarning()
+			return errors.New("failed to create nameserver").Base(err)
 		}
 
 		_, isLocalDNS := server.(*LocalNameServer)
@@ -114,7 +114,7 @@ func NewClient(
 		if len(ns.ExpectedIp) > 0 {
 			expectedMatcher, err = geodata.IPReg.BuildIPMatcher(ns.ExpectedIp)
 			if err != nil {
-				return errors.New("failed to create expected ip matcher").Base(err).AtWarning()
+				return errors.New("failed to create expected ip matcher").Base(err)
 			}
 		}
 
@@ -123,7 +123,7 @@ func NewClient(
 		if len(ns.UnexpectedIp) > 0 {
 			unexpectedMatcher, err = geodata.IPReg.BuildIPMatcher(ns.UnexpectedIp)
 			if err != nil {
-				return errors.New("failed to create unexpected ip matcher").Base(err).AtWarning()
+				return errors.New("failed to create unexpected ip matcher").Base(err)
 			}
 		}
 

app/dns/nameserver_fakedns.go

@@ -27,7 +27,7 @@ func (s *FakeDNSServer) IsDisableCache() bool {
 
 func (f *FakeDNSServer) QueryIP(ctx context.Context, domain string, opt dns.IPOption) ([]net.IP, uint32, error) {
 	if f.fakeDNSEngine == nil {
-		return nil, 0, errors.New("Unable to locate a fake DNS Engine").AtError()
+		return nil, 0, errors.New("Unable to locate a fake DNS Engine")
 	}
 
 	var ips []net.Address
@@ -39,7 +39,7 @@ func (f *FakeDNSServer) QueryIP(ctx context.Context, domain string, opt dns.IPOp
 
 	netIP, err := toNetIP(ips)
 	if err != nil {
-		return nil, 0, errors.New("Unable to convert IP to net ip").Base(err).AtError()
+		return nil, 0, errors.New("Unable to convert IP to net ip").Base(err)
 	}
 
 	errors.LogInfo(ctx, f.Name(), " got answer: ", domain, " -> ", ips)

app/log/log.go

@@ -89,10 +89,10 @@ func (g *Instance) startInternal() error {
 	g.active = true
 
 	if err := g.initAccessLogger(); err != nil {
-		return errors.New("failed to initialize access logger").Base(err).AtWarning()
+		return errors.New("failed to initialize access logger").Base(err)
 	}
 	if err := g.initErrorLogger(); err != nil {
-		return errors.New("failed to initialize error logger").Base(err).AtWarning()
+		return errors.New("failed to initialize error logger").Base(err)
 	}
 
 	return nil
@@ -141,6 +141,10 @@ func (g *Instance) Handle(msg log.Message) {
 	}
 }
 
+func (g *Instance) Severity() log.Severity {
+	return g.config.ErrorLogLevel
+}
+
 // Close implements common.Closable.Close().
 func (g *Instance) Close() error {
 	errors.LogDebug(context.Background(), "Logger closing")

app/proxyman/inbound/always.go

@@ -66,7 +66,7 @@ func NewAlwaysOnInboundHandler(ctx context.Context, tag string, receiverConfig *
 	}
 	mss, err := internet.ToMemoryStreamConfig(receiverConfig.StreamSettings)
 	if err != nil {
-		return nil, errors.New("failed to parse stream config").Base(err).AtWarning()
+		return nil, errors.New("failed to parse stream config").Base(err)
 	}
 
 	newCtx := session.ContextWithInbound(ctx, &session.Inbound{Tag: tag, Source: src})

app/proxyman/inbound/inbound.go

@@ -165,7 +165,7 @@ func NewHandler(ctx context.Context, config *core.InboundHandlerConfig) (inbound
 
 	receiverSettings, ok := rawReceiverSettings.(*proxyman.ReceiverConfig)
 	if !ok {
-		return nil, errors.New("not a ReceiverConfig").AtError()
+		return nil, errors.New("not a ReceiverConfig")
 	}
 
 	streamSettings := receiverSettings.StreamSettings

app/proxyman/inbound/worker.go

@@ -142,7 +142,7 @@ func (w *tcpWorker) Start() error {
 		go w.callback(conn)
 	})
 	if err != nil {
-		return errors.New("failed to listen TCP on ", w.port).AtWarning().Base(err)
+		return errors.New("failed to listen TCP on ", w.port).Base(err)
 	}
 	w.hub = hub
 	return nil
@@ -528,7 +528,7 @@ func (w *dsWorker) Start() error {
 		go w.callback(conn)
 	})
 	if err != nil {
-		return errors.New("failed to listen Unix Domain Socket on ", w.address).AtWarning().Base(err)
+		return errors.New("failed to listen Unix Domain Socket on ", w.address).Base(err)
 	}
 	w.hub = hub
 	return nil

app/proxyman/outbound/handler.go

@@ -87,7 +87,7 @@ func NewHandler(ctx context.Context, config *core.OutboundHandlerConfig) (outbou
 			h.senderSettings = s
 			mss, err := internet.ToMemoryStreamConfig(s.StreamSettings)
 			if err != nil {
-				return nil, errors.New("failed to parse stream settings").Base(err).AtWarning()
+				return nil, errors.New("failed to parse stream settings").Base(err)
 			}
 			h.streamSettings = mss
 		default:
@@ -217,7 +217,7 @@ func (h *Handler) Dispatch(ctx context.Context, link *transport.Link) {
 		if ob.Target.Network == net.Network_UDP && ob.Target.Port == 443 {
 			switch h.udp443 {
 			case "reject":
-				test(errors.New("XUDP rejected UDP/443 traffic").AtInfo())
+				test(errors.New("XUDP rejected UDP/443 traffic"))
 				return
 			case "skip":
 				goto out

app/reverse/portal.go

@@ -68,13 +68,13 @@ func (p *Portal) HandleConnection(ctx context.Context, link *transport.Link) err
 	outbounds := session.OutboundsFromContext(ctx)
 	ob := outbounds[len(outbounds)-1]
 	if ob == nil {
-		return errors.New("outbound metadata not found").AtError()
+		return errors.New("outbound metadata not found")
 	}
 
 	if isDomain(ob.Target, p.domain) {
 		muxClient, err := mux.NewClientWorker(*link, mux.ClientStrategy{})
 		if err != nil {
-			return errors.New("failed to create mux client worker").Base(err).AtWarning()
+			return errors.New("failed to create mux client worker").Base(err)
 		}
 
 		worker, err := NewPortalWorker(muxClient)

app/router/config.go

@@ -115,7 +115,7 @@ func (rr *RoutingRule) BuildCondition() (Condition, error) {
 	}
 
 	if conds.Len() == 0 {
-		return nil, errors.New("this rule has no effective fields").AtWarning()
+		return nil, errors.New("this rule has no effective fields")
 	}
 
 	return conds, nil
@@ -145,7 +145,7 @@ func (br *BalancingRule) Build(ohm outbound.Manager, dispatcher routing.Dispatch
 		}
 		s, ok := i.(*StrategyLeastLoadConfig)
 		if !ok {
-			return nil, errors.New("not a StrategyLeastLoadConfig").AtError()
+			return nil, errors.New("not a StrategyLeastLoadConfig")
 		}
 		leastLoadStrategy := NewLeastLoadStrategy(s)
 		return &Balancer{