Fix Cloudflared edge discovery ignoring configured resolver

2026-06-20 23:32:03 +08:00
parent 4d5c2a03d6
commit b010759f45
2 changed files with 76 additions and 11 deletions
@@ -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
+}