Fix Cloudflared edge discovery ignoring configured resolver

protocol/cloudflare/inbound.go

@@ -9,18 +9,19 @@ import (
 
 	"github.com/sagernet/sing-box/adapter"
 	"github.com/sagernet/sing-box/adapter/inbound"
-	boxDialer "github.com/sagernet/sing-box/common/dialer"
+	"github.com/sagernet/sing-box/common/dialer"
 	C "github.com/sagernet/sing-box/constant"
 	"github.com/sagernet/sing-box/log"
 	"github.com/sagernet/sing-box/option"
 	"github.com/sagernet/sing-box/route/rule"
-	cloudflared "github.com/sagernet/sing-cloudflared"
-	tun "github.com/sagernet/sing-tun"
+	"github.com/sagernet/sing-cloudflared"
+	"github.com/sagernet/sing-tun"
 	"github.com/sagernet/sing/common/bufio"
 	E "github.com/sagernet/sing/common/exceptions"
 	M "github.com/sagernet/sing/common/metadata"
 	N "github.com/sagernet/sing/common/network"
 	"github.com/sagernet/sing/common/pipe"
+	"github.com/sagernet/sing/service"
 )
 
 func RegisterInbound(registry *inbound.Registry) {
@@ -28,28 +29,35 @@ func RegisterInbound(registry *inbound.Registry) {
 }
 
 func NewInbound(ctx context.Context, router adapter.Router, logger log.ContextLogger, tag string, options option.CloudflaredInboundOptions) (adapter.Inbound, error) {
-	controlDialer, err := boxDialer.NewWithOptions(boxDialer.Options{
-		Context:        ctx,
-		Options:        options.ControlDialer,
-		RemoteIsDomain: true,
+	controlDialer, err := dialer.NewWithOptions(dialer.Options{
+		Context:          ctx,
+		Options:          options.ControlDialer,
+		RemoteIsDomain:   true,
+		ResolverOnDetour: true,
 	})
 	if err != nil {
 		return nil, E.Cause(err, "build cloudflared control dialer")
 	}
-	tunnelDialer, err := boxDialer.NewWithOptions(boxDialer.Options{
-		Context:        ctx,
-		Options:        options.TunnelDialer,
-		RemoteIsDomain: true,
+	tunnelDialer, err := dialer.NewWithOptions(dialer.Options{
+		Context:          ctx,
+		Options:          options.TunnelDialer,
+		RemoteIsDomain:   true,
+		ResolverOnDetour: true,
 	})
 	if err != nil {
 		return nil, E.Cause(err, "build cloudflared tunnel dialer")
 	}
+	dnsRouter := service.FromContext[adapter.DNSRouter](ctx)
+	controlResolver := newRouterResolver(dnsRouter, controlDialer.(dialer.ResolveDialer).QueryOptions())
+	tunnelResolver := newRouterResolver(dnsRouter, tunnelDialer.(dialer.ResolveDialer).QueryOptions())
 
 	service, err := cloudflared.NewService(cloudflared.ServiceOptions{
 		Logger:           logger,
 		ConnectionDialer: &routerDialer{router: router, tag: tag},
 		ControlDialer:    controlDialer,
 		TunnelDialer:     tunnelDialer,
+		ControlResolver:  controlResolver,
+		TunnelResolver:   tunnelResolver,
 		ICMPHandler:      &icmpRouterHandler{router: router, logger: logger, tag: tag},
 		ConnContext: func(connCtx context.Context) context.Context {
 			return adapter.WithContext(connCtx, &adapter.InboundContext{

protocol/cloudflare/resolver.go

@@ -0,0 +1,57 @@
+//go:build with_cloudflared
+
+package cloudflare
+
+import (
+	"context"
+	"net"
+	"net/netip"
+	"sort"
+	"strings"
+
+	"github.com/sagernet/sing-box/adapter"
+
+	mDNS "github.com/miekg/dns"
+)
+
+type routerResolver struct {
+	dnsRouter    adapter.DNSRouter
+	queryOptions adapter.DNSQueryOptions
+}
+
+func newRouterResolver(dnsRouter adapter.DNSRouter, queryOptions adapter.DNSQueryOptions) *routerResolver {
+	return &routerResolver{dnsRouter: dnsRouter, queryOptions: queryOptions}
+}
+
+func (r *routerResolver) LookupNetIP(ctx context.Context, host string) ([]netip.Addr, error) {
+	return r.dnsRouter.Lookup(ctx, strings.TrimSuffix(host, "."), r.queryOptions)
+}
+
+func (r *routerResolver) LookupSRV(ctx context.Context, service, proto, name string) ([]*net.SRV, error) {
+	message := &mDNS.Msg{}
+	message.SetQuestion(mDNS.Fqdn("_"+service+"._"+proto+"."+name), mDNS.TypeSRV)
+	response, err := r.dnsRouter.Exchange(ctx, message, r.queryOptions)
+	if err != nil {
+		return nil, err
+	}
+	var records []*net.SRV
+	for _, answer := range response.Answer {
+		record, isSRV := answer.(*mDNS.SRV)
+		if !isSRV {
+			continue
+		}
+		records = append(records, &net.SRV{
+			Target:   record.Target,
+			Port:     record.Port,
+			Priority: record.Priority,
+			Weight:   record.Weight,
+		})
+	}
+	sort.SliceStable(records, func(i, j int) bool {
+		if records[i].Priority != records[j].Priority {
+			return records[i].Priority < records[j].Priority
+		}
+		return records[i].Weight > records[j].Weight
+	})
+	return records, nil
+}