lookup for management domains using an additional timeout

in some cases iOS and macOS may be locked when looking for management domains during network changes

This change introduce an additional timeout on top of the context call

client/internal/dns/mgmt/mgmt.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"fmt"
 	"net"
+	"net/netip"
 	"net/url"
 	"strings"
 	"sync"
@@ -26,6 +27,11 @@ type Resolver struct {
 	mutex         sync.RWMutex
 }
 
+type ipsResponse struct {
+	ips []netip.Addr
+	err error
+}
+
 // NewResolver creates a new management domains cache resolver.
 func NewResolver() *Resolver {
 	return &Resolver{
@@ -99,9 +105,9 @@ func (m *Resolver) AddDomain(ctx context.Context, d domain.Domain) error {
 	ctx, cancel := context.WithTimeout(ctx, dnsTimeout)
 	defer cancel()
 
-	ips, err := net.DefaultResolver.LookupNetIP(ctx, "ip", d.PunycodeString())
+	ips, err := lookupIPWithExtraTimeout(ctx, d)
 	if err != nil {
-		return fmt.Errorf("resolve domain %s: %w", d.SafeString(), err)
+		return err
 	}
 
 	var aRecords, aaaaRecords []dns.RR
@@ -159,6 +165,36 @@ func (m *Resolver) AddDomain(ctx context.Context, d domain.Domain) error {
 	return nil
 }
 
+func lookupIPWithExtraTimeout(ctx context.Context, d domain.Domain) ([]netip.Addr, error) {
+	log.Infof("looking up IP for mgmt domain=%s", d.SafeString())
+	defer log.Infof("done looking up IP for mgmt domain=%s", d.SafeString())
+	errChan := make(chan *ipsResponse, 1)
+
+	go func() {
+		ips, err := net.DefaultResolver.LookupNetIP(ctx, "ip", d.PunycodeString())
+		errChan <- &ipsResponse{
+			err: err,
+			ips: ips,
+		}
+	}()
+
+	var resp *ipsResponse
+
+	select {
+	case <-time.After(dnsTimeout + time.Millisecond*500):
+		log.Warnf("timed out waiting for IP for mgmt domain=%s", d.SafeString())
+		return nil, fmt.Errorf("timed out waiting for ips to be available for domain %s", d.SafeString())
+	case <-ctx.Done():
+		return nil, ctx.Err()
+	case resp = <-errChan:
+	}
+
+	if resp.err != nil {
+		return nil, fmt.Errorf("resolve domain %s: %w", d.SafeString(), resp.err)
+	}
+	return resp.ips, nil
+}
+
 // PopulateFromConfig extracts and caches domains from the client configuration.
 func (m *Resolver) PopulateFromConfig(ctx context.Context, mgmtURL *url.URL) error {
 	if mgmtURL == nil {