// Copyright (c) Tailscale Inc & AUTHORS // SPDX-License-Identifier: BSD-3-Clause package appc import ( "net/netip" "slices" "testing" xmaps "golang.org/x/exp/maps" "golang.org/x/net/dns/dnsmessage" "tailscale.com/util/must" ) func TestUpdateDomains(t *testing.T) { a := NewAppConnector(t.Logf, nil) a.UpdateDomains([]string{"example.com"}) if got, want := a.Domains().AsSlice(), []string{"example.com"}; !slices.Equal(got, want) { t.Errorf("got %v; want %v", got, want) } addr := netip.MustParseAddr("192.0.0.8") a.domains["example.com"] = append(a.domains["example.com"], addr) a.UpdateDomains([]string{"example.com"}) if got, want := a.domains["example.com"], []netip.Addr{addr}; !slices.Equal(got, want) { t.Errorf("got %v; want %v", got, want) } // domains are explicitly downcased on set. a.UpdateDomains([]string{"UP.EXAMPLE.COM"}) if got, want := xmaps.Keys(a.domains), []string{"up.example.com"}; !slices.Equal(got, want) { t.Errorf("got %v; want %v", got, want) } } func TestObserveDNSResponse(t *testing.T) { rc := &routeCollector{} a := NewAppConnector(t.Logf, rc) // a has no domains configured, so it should not advertise any routes a.ObserveDNSResponse(dnsResponse("example.com.", "192.0.0.8")) if got, want := rc.routes, ([]netip.Prefix)(nil); !slices.Equal(got, want) { t.Errorf("got %v; want %v", got, want) } wantRoutes := []netip.Prefix{netip.MustParsePrefix("192.0.0.8/32")} a.UpdateDomains([]string{"example.com"}) a.ObserveDNSResponse(dnsResponse("example.com.", "192.0.0.8")) if got, want := rc.routes, wantRoutes; !slices.Equal(got, want) { t.Errorf("got %v; want %v", got, want) } wantRoutes = append(wantRoutes, netip.MustParsePrefix("2001:db8::1/128")) a.ObserveDNSResponse(dnsResponse("example.com.", "2001:db8::1")) if got, want := rc.routes, wantRoutes; !slices.Equal(got, want) { t.Errorf("got %v; want %v", got, want) } // don't re-advertise routes that have already been advertised a.ObserveDNSResponse(dnsResponse("example.com.", "2001:db8::1")) if !slices.Equal(rc.routes, wantRoutes) { t.Errorf("got %v; want %v", rc.routes, wantRoutes) } } func TestWildcardDomains(t *testing.T) { rc := &routeCollector{} a := NewAppConnector(t.Logf, rc) a.UpdateDomains([]string{"*.example.com"}) a.ObserveDNSResponse(dnsResponse("foo.example.com.", "192.0.0.8")) if got, want := rc.routes, []netip.Prefix{netip.MustParsePrefix("192.0.0.8/32")}; !slices.Equal(got, want) { t.Errorf("routes: got %v; want %v", got, want) } if got, want := a.wildcards, []string{"example.com"}; !slices.Equal(got, want) { t.Errorf("wildcards: got %v; want %v", got, want) } a.UpdateDomains([]string{"*.example.com", "example.com"}) if _, ok := a.domains["foo.example.com"]; !ok { t.Errorf("expected foo.example.com to be preserved in domains due to wildcard") } if got, want := a.wildcards, []string{"example.com"}; !slices.Equal(got, want) { t.Errorf("wildcards: got %v; want %v", got, want) } // There was an early regression where the wildcard domain was added repeatedly, this guards against that. a.UpdateDomains([]string{"*.example.com", "example.com"}) if len(a.wildcards) != 1 { t.Errorf("expected only one wildcard domain, got %v", a.wildcards) } } // dnsResponse is a test helper that creates a DNS response buffer for the given domain and address func dnsResponse(domain, address string) []byte { addr := netip.MustParseAddr(address) b := dnsmessage.NewBuilder(nil, dnsmessage.Header{}) b.EnableCompression() b.StartAnswers() switch addr.BitLen() { case 32: b.AResource( dnsmessage.ResourceHeader{ Name: dnsmessage.MustNewName(domain), Type: dnsmessage.TypeA, Class: dnsmessage.ClassINET, TTL: 0, }, dnsmessage.AResource{ A: addr.As4(), }, ) case 128: b.AAAAResource( dnsmessage.ResourceHeader{ Name: dnsmessage.MustNewName(domain), Type: dnsmessage.TypeAAAA, Class: dnsmessage.ClassINET, TTL: 0, }, dnsmessage.AAAAResource{ AAAA: addr.As16(), }, ) default: panic("invalid address length") } return must.Get(b.Finish()) } // routeCollector is a test helper that collects the list of routes advertised type routeCollector struct { routes []netip.Prefix } // routeCollector implements RouteAdvertiser var _ RouteAdvertiser = (*routeCollector)(nil) func (rc *routeCollector) AdvertiseRoute(pfx netip.Prefix) error { rc.routes = append(rc.routes, pfx) return nil }