// Copyright 2009 The Go Authors. All rights reserved. // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. package net import ( "bytes" "context" "fmt" "internal/testenv" "reflect" "runtime" "sort" "strings" "testing" "time" ) func lookupLocalhost(ctx context.Context, fn func(context.Context, string) ([]IPAddr, error), host string) ([]IPAddr, error) { switch host { case "localhost": return []IPAddr{ {IP: IPv4(127, 0, 0, 1)}, {IP: IPv6loopback}, }, nil default: return fn(ctx, host) } } // The Lookup APIs use various sources such as local database, DNS or // mDNS, and may use platform-dependent DNS stub resolver if possible. // The APIs accept any of forms for a query; host name in various // encodings, UTF-8 encoded net name, domain name, FQDN or absolute // FQDN, but the result would be one of the forms and it depends on // the circumstances. var lookupGoogleSRVTests = []struct { service, proto, name string cname, target string }{ { "xmpp-server", "tcp", "google.com", "google.com.", "google.com.", }, { "xmpp-server", "tcp", "google.com.", "google.com.", "google.com.", }, // non-standard back door { "", "", "_xmpp-server._tcp.google.com", "google.com.", "google.com.", }, { "", "", "_xmpp-server._tcp.google.com.", "google.com.", "google.com.", }, } func TestLookupGoogleSRV(t *testing.T) { if testenv.Builder() == "" { testenv.MustHaveExternalNetwork(t) } if !supportsIPv4() || !*testIPv4 { t.Skip("IPv4 is required") } for _, tt := range lookupGoogleSRVTests { cname, srvs, err := LookupSRV(tt.service, tt.proto, tt.name) if err != nil { testenv.SkipFlakyNet(t) t.Fatal(err) } if len(srvs) == 0 { t.Error("got no record") } if !strings.HasSuffix(cname, tt.cname) { t.Errorf("got %s; want %s", cname, tt.cname) } for _, srv := range srvs { if !strings.HasSuffix(srv.Target, tt.target) { t.Errorf("got %v; want a record containing %s", srv, tt.target) } } } } var lookupGmailMXTests = []struct { name, host string }{ {"gmail.com", "google.com."}, {"gmail.com.", "google.com."}, } func TestLookupGmailMX(t *testing.T) { if testenv.Builder() == "" { testenv.MustHaveExternalNetwork(t) } if !supportsIPv4() || !*testIPv4 { t.Skip("IPv4 is required") } defer dnsWaitGroup.Wait() for _, tt := range lookupGmailMXTests { mxs, err := LookupMX(tt.name) if err != nil { t.Fatal(err) } if len(mxs) == 0 { t.Error("got no record") } for _, mx := range mxs { if !strings.HasSuffix(mx.Host, tt.host) { t.Errorf("got %v; want a record containing %s", mx, tt.host) } } } } var lookupGmailNSTests = []struct { name, host string }{ {"gmail.com", "google.com."}, {"gmail.com.", "google.com."}, } func TestLookupGmailNS(t *testing.T) { if testenv.Builder() == "" { testenv.MustHaveExternalNetwork(t) } if !supportsIPv4() || !*testIPv4 { t.Skip("IPv4 is required") } defer dnsWaitGroup.Wait() for _, tt := range lookupGmailNSTests { nss, err := LookupNS(tt.name) if err != nil { testenv.SkipFlakyNet(t) t.Fatal(err) } if len(nss) == 0 { t.Error("got no record") } for _, ns := range nss { if !strings.HasSuffix(ns.Host, tt.host) { t.Errorf("got %v; want a record containing %s", ns, tt.host) } } } } var lookupGmailTXTTests = []struct { name, txt, host string }{ {"gmail.com", "spf", "google.com"}, {"gmail.com.", "spf", "google.com"}, } func TestLookupGmailTXT(t *testing.T) { if testenv.Builder() == "" { testenv.MustHaveExternalNetwork(t) } if !supportsIPv4() || !*testIPv4 { t.Skip("IPv4 is required") } defer dnsWaitGroup.Wait() for _, tt := range lookupGmailTXTTests { txts, err := LookupTXT(tt.name) if err != nil { t.Fatal(err) } if len(txts) == 0 { t.Error("got no record") } found := false for _, txt := range txts { if strings.Contains(txt, tt.txt) && (strings.HasSuffix(txt, tt.host) || strings.HasSuffix(txt, tt.host+".")) { found = true break } } if !found { t.Errorf("got %v; want a record containing %s, %s", txts, tt.txt, tt.host) } } } var lookupGooglePublicDNSAddrTests = []struct { addr, name string }{ {"8.8.8.8", ".google.com."}, {"8.8.4.4", ".google.com."}, {"2001:4860:4860::8888", ".google.com."}, {"2001:4860:4860::8844", ".google.com."}, } func TestLookupGooglePublicDNSAddr(t *testing.T) { if testenv.Builder() == "" { testenv.MustHaveExternalNetwork(t) } if !supportsIPv4() || !supportsIPv6() || !*testIPv4 || !*testIPv6 { t.Skip("both IPv4 and IPv6 are required") } defer dnsWaitGroup.Wait() for _, tt := range lookupGooglePublicDNSAddrTests { names, err := LookupAddr(tt.addr) if err != nil { t.Fatal(err) } if len(names) == 0 { t.Error("got no record") } for _, name := range names { if !strings.HasSuffix(name, tt.name) { t.Errorf("got %s; want a record containing %s", name, tt.name) } } } } func TestLookupIPv6LinkLocalAddr(t *testing.T) { if !supportsIPv6() || !*testIPv6 { t.Skip("IPv6 is required") } defer dnsWaitGroup.Wait() addrs, err := LookupHost("localhost") if err != nil { t.Fatal(err) } found := false for _, addr := range addrs { if addr == "fe80::1%lo0" { found = true break } } if !found { t.Skipf("not supported on %s", runtime.GOOS) } if _, err := LookupAddr("fe80::1%lo0"); err != nil { t.Error(err) } } var lookupCNAMETests = []struct { name, cname string }{ {"www.iana.org", "icann.org."}, {"www.iana.org.", "icann.org."}, {"www.google.com", "google.com."}, } func TestLookupCNAME(t *testing.T) { if testenv.Builder() == "" { testenv.MustHaveExternalNetwork(t) } if !supportsIPv4() || !*testIPv4 { t.Skip("IPv4 is required") } defer dnsWaitGroup.Wait() for _, tt := range lookupCNAMETests { cname, err := LookupCNAME(tt.name) if err != nil { t.Fatal(err) } if !strings.HasSuffix(cname, tt.cname) { t.Errorf("got %s; want a record containing %s", cname, tt.cname) } } } var lookupGoogleHostTests = []struct { name string }{ {"google.com"}, {"google.com."}, } func TestLookupGoogleHost(t *testing.T) { if testenv.Builder() == "" { testenv.MustHaveExternalNetwork(t) } if !supportsIPv4() || !*testIPv4 { t.Skip("IPv4 is required") } defer dnsWaitGroup.Wait() for _, tt := range lookupGoogleHostTests { addrs, err := LookupHost(tt.name) if err != nil { t.Fatal(err) } if len(addrs) == 0 { t.Error("got no record") } for _, addr := range addrs { if ParseIP(addr) == nil { t.Errorf("got %q; want a literal IP address", addr) } } } } func TestLookupLongTXT(t *testing.T) { if runtime.GOOS == "plan9" { t.Skip("skipping on plan9; see https://golang.org/issue/22857") } if testenv.Builder() == "" { testenv.MustHaveExternalNetwork(t) } defer dnsWaitGroup.Wait() txts, err := LookupTXT("golang.rsc.io") if err != nil { t.Fatal(err) } sort.Strings(txts) want := []string{ strings.Repeat("abcdefghijklmnopqrstuvwxyABCDEFGHJIKLMNOPQRSTUVWXY", 10), "gophers rule", } if !reflect.DeepEqual(txts, want) { t.Fatalf("LookupTXT golang.rsc.io incorrect\nhave %q\nwant %q", txts, want) } } var lookupGoogleIPTests = []struct { name string }{ {"google.com"}, {"google.com."}, } func TestLookupGoogleIP(t *testing.T) { if testenv.Builder() == "" { testenv.MustHaveExternalNetwork(t) } if !supportsIPv4() || !*testIPv4 { t.Skip("IPv4 is required") } defer dnsWaitGroup.Wait() for _, tt := range lookupGoogleIPTests { ips, err := LookupIP(tt.name) if err != nil { t.Fatal(err) } if len(ips) == 0 { t.Error("got no record") } for _, ip := range ips { if ip.To4() == nil && ip.To16() == nil { t.Errorf("got %v; want an IP address", ip) } } } } var revAddrTests = []struct { Addr string Reverse string ErrPrefix string }{ {"1.2.3.4", "4.3.2.1.in-addr.arpa.", ""}, {"245.110.36.114", "114.36.110.245.in-addr.arpa.", ""}, {"::ffff:12.34.56.78", "78.56.34.12.in-addr.arpa.", ""}, {"::1", "1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.ip6.arpa.", ""}, {"1::", "0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.1.0.0.0.ip6.arpa.", ""}, {"1234:567::89a:bcde", "e.d.c.b.a.9.8.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.7.6.5.0.4.3.2.1.ip6.arpa.", ""}, {"1234:567:fefe:bcbc:adad:9e4a:89a:bcde", "e.d.c.b.a.9.8.0.a.4.e.9.d.a.d.a.c.b.c.b.e.f.e.f.7.6.5.0.4.3.2.1.ip6.arpa.", ""}, {"1.2.3", "", "unrecognized address"}, {"1.2.3.4.5", "", "unrecognized address"}, {"1234:567:bcbca::89a:bcde", "", "unrecognized address"}, {"1234:567::bcbc:adad::89a:bcde", "", "unrecognized address"}, } func TestReverseAddress(t *testing.T) { defer dnsWaitGroup.Wait() for i, tt := range revAddrTests { a, err := reverseaddr(tt.Addr) if len(tt.ErrPrefix) > 0 && err == nil { t.Errorf("#%d: expected %q, got (error)", i, tt.ErrPrefix) continue } if len(tt.ErrPrefix) == 0 && err != nil { t.Errorf("#%d: expected , got %q (error)", i, err) } if err != nil && err.(*DNSError).Err != tt.ErrPrefix { t.Errorf("#%d: expected %q, got %q (mismatched error)", i, tt.ErrPrefix, err.(*DNSError).Err) } if a != tt.Reverse { t.Errorf("#%d: expected %q, got %q (reverse address)", i, tt.Reverse, a) } } } func TestDNSFlood(t *testing.T) { if !*testDNSFlood { t.Skip("test disabled; use -dnsflood to enable") } defer dnsWaitGroup.Wait() var N = 5000 if runtime.GOOS == "darwin" { // On Darwin this test consumes kernel threads much // than other platforms for some reason. // When we monitor the number of allocated Ms by // observing on runtime.newm calls, we can see that it // easily reaches the per process ceiling // kern.num_threads when CGO_ENABLED=1 and // GODEBUG=netdns=go. N = 500 } const timeout = 3 * time.Second ctxHalfTimeout, cancel := context.WithTimeout(context.Background(), timeout/2) defer cancel() ctxTimeout, cancel := context.WithTimeout(context.Background(), timeout) defer cancel() c := make(chan error, 2*N) for i := 0; i < N; i++ { name := fmt.Sprintf("%d.net-test.golang.org", i) go func() { _, err := DefaultResolver.LookupIPAddr(ctxHalfTimeout, name) c <- err }() go func() { _, err := DefaultResolver.LookupIPAddr(ctxTimeout, name) c <- err }() } qstats := struct { succeeded, failed int timeout, temporary, other int unknown int }{} deadline := time.After(timeout + time.Second) for i := 0; i < 2*N; i++ { select { case <-deadline: t.Fatal("deadline exceeded") case err := <-c: switch err := err.(type) { case nil: qstats.succeeded++ case Error: qstats.failed++ if err.Timeout() { qstats.timeout++ } if err.Temporary() { qstats.temporary++ } if !err.Timeout() && !err.Temporary() { qstats.other++ } default: qstats.failed++ qstats.unknown++ } } } // A high volume of DNS queries for sub-domain of golang.org // would be coordinated by authoritative or recursive server, // or stub resolver which implements query-response rate // limitation, so we can expect some query successes and more // failures including timeout, temporary and other here. // As a rule, unknown must not be shown but it might possibly // happen due to issue 4856 for now. t.Logf("%v succeeded, %v failed (%v timeout, %v temporary, %v other, %v unknown)", qstats.succeeded, qstats.failed, qstats.timeout, qstats.temporary, qstats.other, qstats.unknown) } func TestLookupDotsWithLocalSource(t *testing.T) { if !supportsIPv4() || !*testIPv4 { t.Skip("IPv4 is required") } if testenv.Builder() == "" { testenv.MustHaveExternalNetwork(t) } defer dnsWaitGroup.Wait() for i, fn := range []func() func(){forceGoDNS, forceCgoDNS} { fixup := fn() if fixup == nil { continue } names, err := LookupAddr("127.0.0.1") fixup() if err != nil { t.Logf("#%d: %v", i, err) continue } mode := "netgo" if i == 1 { mode = "netcgo" } loop: for i, name := range names { if strings.Index(name, ".") == len(name)-1 { // "localhost" not "localhost." for j := range names { if j == i { continue } if names[j] == name[:len(name)-1] { // It's OK if we find the name without the dot, // as some systems say 127.0.0.1 localhost localhost. continue loop } } t.Errorf("%s: got %s; want %s", mode, name, name[:len(name)-1]) } else if strings.Contains(name, ".") && !strings.HasSuffix(name, ".") { // "localhost.localdomain." not "localhost.localdomain" t.Errorf("%s: got %s; want name ending with trailing dot", mode, name) } } } } func TestLookupDotsWithRemoteSource(t *testing.T) { if testenv.Builder() == "" { testenv.MustHaveExternalNetwork(t) } if !supportsIPv4() || !*testIPv4 { t.Skip("IPv4 is required") } defer dnsWaitGroup.Wait() if fixup := forceGoDNS(); fixup != nil { testDots(t, "go") fixup() } if fixup := forceCgoDNS(); fixup != nil { testDots(t, "cgo") fixup() } } func testDots(t *testing.T, mode string) { names, err := LookupAddr("8.8.8.8") // Google dns server if err != nil { testenv.SkipFlakyNet(t) t.Errorf("LookupAddr(8.8.8.8): %v (mode=%v)", err, mode) } else { for _, name := range names { if !strings.HasSuffix(name, ".google.com.") { t.Errorf("LookupAddr(8.8.8.8) = %v, want names ending in .google.com. with trailing dot (mode=%v)", names, mode) break } } } cname, err := LookupCNAME("www.mit.edu") if err != nil { testenv.SkipFlakyNet(t) t.Errorf("LookupCNAME(www.mit.edu, mode=%v): %v", mode, err) } else if !strings.HasSuffix(cname, ".") { t.Errorf("LookupCNAME(www.mit.edu) = %v, want cname ending in . with trailing dot (mode=%v)", cname, mode) } mxs, err := LookupMX("google.com") if err != nil { testenv.SkipFlakyNet(t) t.Errorf("LookupMX(google.com): %v (mode=%v)", err, mode) } else { for _, mx := range mxs { if !strings.HasSuffix(mx.Host, ".google.com.") { t.Errorf("LookupMX(google.com) = %v, want names ending in .google.com. with trailing dot (mode=%v)", mxString(mxs), mode) break } } } nss, err := LookupNS("google.com") if err != nil { testenv.SkipFlakyNet(t) t.Errorf("LookupNS(google.com): %v (mode=%v)", err, mode) } else { for _, ns := range nss { if !strings.HasSuffix(ns.Host, ".google.com.") { t.Errorf("LookupNS(google.com) = %v, want names ending in .google.com. with trailing dot (mode=%v)", nsString(nss), mode) break } } } cname, srvs, err := LookupSRV("xmpp-server", "tcp", "google.com") if err != nil { testenv.SkipFlakyNet(t) t.Errorf("LookupSRV(xmpp-server, tcp, google.com): %v (mode=%v)", err, mode) } else { if !strings.HasSuffix(cname, ".google.com.") { t.Errorf("LookupSRV(xmpp-server, tcp, google.com) returned cname=%v, want name ending in .google.com. with trailing dot (mode=%v)", cname, mode) } for _, srv := range srvs { if !strings.HasSuffix(srv.Target, ".google.com.") { t.Errorf("LookupSRV(xmpp-server, tcp, google.com) returned addrs=%v, want names ending in .google.com. with trailing dot (mode=%v)", srvString(srvs), mode) break } } } } func mxString(mxs []*MX) string { var buf bytes.Buffer sep := "" fmt.Fprintf(&buf, "[") for _, mx := range mxs { fmt.Fprintf(&buf, "%s%s:%d", sep, mx.Host, mx.Pref) sep = " " } fmt.Fprintf(&buf, "]") return buf.String() } func nsString(nss []*NS) string { var buf bytes.Buffer sep := "" fmt.Fprintf(&buf, "[") for _, ns := range nss { fmt.Fprintf(&buf, "%s%s", sep, ns.Host) sep = " " } fmt.Fprintf(&buf, "]") return buf.String() } func srvString(srvs []*SRV) string { var buf bytes.Buffer sep := "" fmt.Fprintf(&buf, "[") for _, srv := range srvs { fmt.Fprintf(&buf, "%s%s:%d:%d:%d", sep, srv.Target, srv.Port, srv.Priority, srv.Weight) sep = " " } fmt.Fprintf(&buf, "]") return buf.String() } func TestLookupPort(t *testing.T) { // See http://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml // // Please be careful about adding new test cases. // There are platforms having incomplete mappings for // restricted resource access and security reasons. type test struct { network string name string port int ok bool } var tests = []test{ {"tcp", "0", 0, true}, {"udp", "0", 0, true}, {"udp", "domain", 53, true}, {"--badnet--", "zzz", 0, false}, {"tcp", "--badport--", 0, false}, {"tcp", "-1", 0, false}, {"tcp", "65536", 0, false}, {"udp", "-1", 0, false}, {"udp", "65536", 0, false}, {"tcp", "123456789", 0, false}, // Issue 13610: LookupPort("tcp", "") {"tcp", "", 0, true}, {"tcp4", "", 0, true}, {"tcp6", "", 0, true}, {"udp", "", 0, true}, {"udp4", "", 0, true}, {"udp6", "", 0, true}, } switch runtime.GOOS { case "android": if netGo { t.Skipf("not supported on %s without cgo; see golang.org/issues/14576", runtime.GOOS) } default: tests = append(tests, test{"tcp", "http", 80, true}) } for _, tt := range tests { port, err := LookupPort(tt.network, tt.name) if port != tt.port || (err == nil) != tt.ok { t.Errorf("LookupPort(%q, %q) = %d, %v; want %d, error=%t", tt.network, tt.name, port, err, tt.port, !tt.ok) } if err != nil { if perr := parseLookupPortError(err); perr != nil { t.Error(perr) } } } } // Like TestLookupPort but with minimal tests that should always pass // because the answers are baked-in to the net package. func TestLookupPort_Minimal(t *testing.T) { type test struct { network string name string port int } var tests = []test{ {"tcp", "http", 80}, {"tcp", "HTTP", 80}, // case shouldn't matter {"tcp", "https", 443}, {"tcp", "ssh", 22}, {"tcp", "gopher", 70}, {"tcp4", "http", 80}, {"tcp6", "http", 80}, } for _, tt := range tests { port, err := LookupPort(tt.network, tt.name) if port != tt.port || err != nil { t.Errorf("LookupPort(%q, %q) = %d, %v; want %d, error=nil", tt.network, tt.name, port, err, tt.port) } } } func TestLookupProtocol_Minimal(t *testing.T) { type test struct { name string want int } var tests = []test{ {"tcp", 6}, {"TcP", 6}, // case shouldn't matter {"icmp", 1}, {"igmp", 2}, {"udp", 17}, {"ipv6-icmp", 58}, } for _, tt := range tests { got, err := lookupProtocol(context.Background(), tt.name) if got != tt.want || err != nil { t.Errorf("LookupProtocol(%q) = %d, %v; want %d, error=nil", tt.name, got, err, tt.want) } } } func TestLookupNonLDH(t *testing.T) { if runtime.GOOS == "nacl" { t.Skip("skip on nacl") } defer dnsWaitGroup.Wait() if fixup := forceGoDNS(); fixup != nil { defer fixup() } // "LDH" stands for letters, digits, and hyphens and is the usual // description of standard DNS names. // This test is checking that other kinds of names are reported // as not found, not reported as invalid names. addrs, err := LookupHost("!!!.###.bogus..domain.") if err == nil { t.Fatalf("lookup succeeded: %v", addrs) } if !strings.HasSuffix(err.Error(), errNoSuchHost.Error()) { t.Fatalf("lookup error = %v, want %v", err, errNoSuchHost) } } func TestLookupContextCancel(t *testing.T) { if testenv.Builder() == "" { testenv.MustHaveExternalNetwork(t) } if runtime.GOOS == "nacl" { t.Skip("skip on nacl") } defer dnsWaitGroup.Wait() ctx, ctxCancel := context.WithCancel(context.Background()) ctxCancel() _, err := DefaultResolver.LookupIPAddr(ctx, "google.com") if err != errCanceled { testenv.SkipFlakyNet(t) t.Fatal(err) } ctx = context.Background() _, err = DefaultResolver.LookupIPAddr(ctx, "google.com") if err != nil { testenv.SkipFlakyNet(t) t.Fatal(err) } }