// Copyright (c) 2020 Tailscale Inc & 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 tsdns import ( "bytes" "errors" "net" "sync" "testing" dns "golang.org/x/net/dns/dnsmessage" "inet.af/netaddr" "tailscale.com/tstest" ) var testipv4 = netaddr.IPv4(1, 2, 3, 4) var testipv6 = netaddr.IPv6Raw([16]byte{ 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, }) var dnsMap = NewMap( map[string]netaddr.IP{ "test1.ipn.dev.": testipv4, "test2.ipn.dev.": testipv6, }, []string{"ipn.dev."}, ) func dnspacket(domain string, tp dns.Type) []byte { var dnsHeader dns.Header question := dns.Question{ Name: dns.MustNewName(domain), Type: tp, Class: dns.ClassINET, } builder := dns.NewBuilder(nil, dnsHeader) builder.StartQuestions() builder.Question(question) payload, _ := builder.Finish() return payload } type dnsResponse struct { ip netaddr.IP name string rcode dns.RCode } func unpackResponse(payload []byte) (dnsResponse, error) { var response dnsResponse var parser dns.Parser h, err := parser.Start(payload) if err != nil { return response, err } if !h.Response { return response, errors.New("not a response") } response.rcode = h.RCode if response.rcode != dns.RCodeSuccess { return response, nil } err = parser.SkipAllQuestions() if err != nil { return response, err } ah, err := parser.AnswerHeader() if err != nil { return response, err } switch ah.Type { case dns.TypeA: res, err := parser.AResource() if err != nil { return response, err } response.ip = netaddr.IPv4(res.A[0], res.A[1], res.A[2], res.A[3]) case dns.TypeAAAA: res, err := parser.AAAAResource() if err != nil { return response, err } response.ip = netaddr.IPv6Raw(res.AAAA) case dns.TypeNS: res, err := parser.NSResource() if err != nil { return response, err } response.name = res.NS.String() default: return response, errors.New("type not in {A, AAAA, NS}") } return response, nil } func syncRespond(r *Resolver, query []byte) ([]byte, error) { request := Packet{Payload: query} r.EnqueueRequest(request) resp, err := r.NextResponse() return resp.Payload, err } func mustIP(str string) netaddr.IP { ip, err := netaddr.ParseIP(str) if err != nil { panic(err) } return ip } func TestRDNSNameToIPv4(t *testing.T) { tests := []struct { name string input string wantIP netaddr.IP wantOK bool }{ {"valid", "4.123.24.1.in-addr.arpa.", netaddr.IPv4(1, 24, 123, 4), true}, {"double_dot", "1..2.3.in-addr.arpa.", netaddr.IP{}, false}, {"overflow", "1.256.3.4.in-addr.arpa.", netaddr.IP{}, false}, {"not_ip", "sub.do.ma.in.in-addr.arpa.", netaddr.IP{}, false}, } for _, tt := range tests { t.Run(tt.name, func(t *testing.T) { ip, ok := rdnsNameToIPv4(tt.input) if ok != tt.wantOK { t.Errorf("ok = %v; want %v", ok, tt.wantOK) } else if ok && ip != tt.wantIP { t.Errorf("ip = %v; want %v", ip, tt.wantIP) } }) } } func TestRDNSNameToIPv6(t *testing.T) { tests := []struct { name string input string wantIP netaddr.IP wantOK bool }{ { "valid", "b.a.9.8.7.6.5.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa.", mustIP("2001:db8::567:89ab"), true, }, { "double_dot", "b..9.8.7.6.5.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa.", netaddr.IP{}, false, }, { "double_hex", "b.a.98.0.7.6.5.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa.", netaddr.IP{}, false, }, { "not_hex", "b.a.g.0.7.6.5.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa.", netaddr.IP{}, false, }, } for _, tt := range tests { t.Run(tt.name, func(t *testing.T) { ip, ok := rdnsNameToIPv6(tt.input) if ok != tt.wantOK { t.Errorf("ok = %v; want %v", ok, tt.wantOK) } else if ok && ip != tt.wantIP { t.Errorf("ip = %v; want %v", ip, tt.wantIP) } }) } } func TestResolve(t *testing.T) { r := NewResolver(ResolverConfig{Logf: t.Logf, Forward: false}) r.SetMap(dnsMap) if err := r.Start(); err != nil { t.Fatalf("start: %v", err) } defer r.Close() tests := []struct { name string qname string qtype dns.Type ip netaddr.IP code dns.RCode }{ {"ipv4", "test1.ipn.dev.", dns.TypeA, testipv4, dns.RCodeSuccess}, {"ipv6", "test2.ipn.dev.", dns.TypeAAAA, testipv6, dns.RCodeSuccess}, {"no-ipv6", "test1.ipn.dev.", dns.TypeAAAA, netaddr.IP{}, dns.RCodeSuccess}, {"nxdomain", "test3.ipn.dev.", dns.TypeA, netaddr.IP{}, dns.RCodeNameError}, {"foreign domain", "google.com.", dns.TypeA, netaddr.IP{}, dns.RCodeRefused}, {"all", "test1.ipn.dev.", dns.TypeA, testipv4, dns.RCodeSuccess}, {"mx-ipv4", "test1.ipn.dev.", dns.TypeMX, netaddr.IP{}, dns.RCodeSuccess}, {"mx-ipv6", "test2.ipn.dev.", dns.TypeMX, netaddr.IP{}, dns.RCodeSuccess}, {"mx-nxdomain", "test3.ipn.dev.", dns.TypeMX, netaddr.IP{}, dns.RCodeNameError}, {"ns-nxdomain", "test3.ipn.dev.", dns.TypeNS, netaddr.IP{}, dns.RCodeNameError}, } for _, tt := range tests { t.Run(tt.name, func(t *testing.T) { ip, code, err := r.Resolve(tt.qname, tt.qtype) if err != nil { t.Errorf("err = %v; want nil", err) } if code != tt.code { t.Errorf("code = %v; want %v", code, tt.code) } // Only check ip for non-err if ip != tt.ip { t.Errorf("ip = %v; want %v", ip, tt.ip) } }) } } func TestResolveReverse(t *testing.T) { r := NewResolver(ResolverConfig{Logf: t.Logf, Forward: false}) r.SetMap(dnsMap) if err := r.Start(); err != nil { t.Fatalf("start: %v", err) } defer r.Close() tests := []struct { name string ip netaddr.IP want string code dns.RCode }{ {"ipv4", testipv4, "test1.ipn.dev.", dns.RCodeSuccess}, {"ipv6", testipv6, "test2.ipn.dev.", dns.RCodeSuccess}, {"nxdomain", netaddr.IPv4(4, 3, 2, 1), "", dns.RCodeNameError}, } for _, tt := range tests { t.Run(tt.name, func(t *testing.T) { name, code, err := r.ResolveReverse(tt.ip) if err != nil { t.Errorf("err = %v; want nil", err) } if code != tt.code { t.Errorf("code = %v; want %v", code, tt.code) } if name != tt.want { t.Errorf("ip = %v; want %v", name, tt.want) } }) } } func ipv6Works() bool { c, err := net.Listen("tcp", "[::1]:0") if err != nil { return false } c.Close() return true } func TestDelegate(t *testing.T) { tstest.ResourceCheck(t) if !ipv6Works() { t.Skip("skipping test that requires localhost IPv6") } dnsHandleFunc("test.site.", resolveToIP(testipv4, testipv6, "dns.test.site.")) dnsHandleFunc("nxdomain.site.", resolveToNXDOMAIN) v4server, v4errch := serveDNS(t, "127.0.0.1:0") v6server, v6errch := serveDNS(t, "[::1]:0") defer func() { if err := <-v4errch; err != nil { t.Errorf("v4 server error: %v", err) } if err := <-v6errch; err != nil { t.Errorf("v6 server error: %v", err) } }() if v4server != nil { defer v4server.Shutdown() } if v6server != nil { defer v6server.Shutdown() } if v4server == nil || v6server == nil { // There is an error in at least one of the channels // and we cannot proceed; return to see it. return } r := NewResolver(ResolverConfig{Logf: t.Logf, Forward: true}) r.SetMap(dnsMap) r.SetUpstreams([]net.Addr{ v4server.PacketConn.LocalAddr(), v6server.PacketConn.LocalAddr(), }) if err := r.Start(); err != nil { t.Fatalf("start: %v", err) } defer r.Close() tests := []struct { title string query []byte response dnsResponse }{ { "ipv4", dnspacket("test.site.", dns.TypeA), dnsResponse{ip: testipv4, rcode: dns.RCodeSuccess}, }, { "ipv6", dnspacket("test.site.", dns.TypeAAAA), dnsResponse{ip: testipv6, rcode: dns.RCodeSuccess}, }, { "ns", dnspacket("test.site.", dns.TypeNS), dnsResponse{name: "dns.test.site.", rcode: dns.RCodeSuccess}, }, { "nxdomain", dnspacket("nxdomain.site.", dns.TypeA), dnsResponse{rcode: dns.RCodeNameError}, }, } for _, tt := range tests { t.Run(tt.title, func(t *testing.T) { payload, err := syncRespond(r, tt.query) if err != nil { t.Errorf("err = %v; want nil", err) return } response, err := unpackResponse(payload) if err != nil { t.Errorf("extract: err = %v; want nil (in %x)", err, payload) return } if response.rcode != tt.response.rcode { t.Errorf("rcode = %v; want %v", response.rcode, tt.response.rcode) } if response.ip != tt.response.ip { t.Errorf("ip = %v; want %v", response.ip, tt.response.ip) } if response.name != tt.response.name { t.Errorf("name = %v; want %v", response.name, tt.response.name) } }) } } func TestDelegateCollision(t *testing.T) { dnsHandleFunc("test.site.", resolveToIP(testipv4, testipv6, "dns.test.site.")) server, errch := serveDNS(t, "127.0.0.1:0") defer func() { if err := <-errch; err != nil { t.Errorf("server error: %v", err) } }() if server == nil { return } defer server.Shutdown() r := NewResolver(ResolverConfig{Logf: t.Logf, Forward: true}) r.SetMap(dnsMap) r.SetUpstreams([]net.Addr{server.PacketConn.LocalAddr()}) if err := r.Start(); err != nil { t.Fatalf("start: %v", err) } defer r.Close() packets := []struct { qname string qtype dns.Type addr netaddr.IPPort }{ {"test.site.", dns.TypeA, netaddr.IPPort{IP: netaddr.IPv4(1, 1, 1, 1), Port: 1001}}, {"test.site.", dns.TypeAAAA, netaddr.IPPort{IP: netaddr.IPv4(1, 1, 1, 1), Port: 1002}}, } // packets will have the same dns txid. for _, p := range packets { payload := dnspacket(p.qname, p.qtype) req := Packet{Payload: payload, Addr: p.addr} err := r.EnqueueRequest(req) if err != nil { t.Error(err) } } // Despite the txid collision, the answer(s) should still match the query. resp, err := r.NextResponse() if err != nil { t.Error(err) } var p dns.Parser _, err = p.Start(resp.Payload) if err != nil { t.Error(err) } err = p.SkipAllQuestions() if err != nil { t.Error(err) } ans, err := p.AllAnswers() if err != nil { t.Error(err) } var wantType dns.Type switch ans[0].Body.(type) { case *dns.AResource: wantType = dns.TypeA case *dns.AAAAResource: wantType = dns.TypeAAAA default: t.Errorf("unexpected answer type: %T", ans[0].Body) } for _, p := range packets { if p.qtype == wantType && p.addr != resp.Addr { t.Errorf("addr = %v; want %v", resp.Addr, p.addr) } } } func TestConcurrentSetMap(t *testing.T) { r := NewResolver(ResolverConfig{Logf: t.Logf, Forward: false}) if err := r.Start(); err != nil { t.Fatalf("start: %v", err) } defer r.Close() // This is purely to ensure that Resolve does not race with SetMap. var wg sync.WaitGroup wg.Add(2) go func() { defer wg.Done() r.SetMap(dnsMap) }() go func() { defer wg.Done() r.Resolve("test1.ipn.dev", dns.TypeA) }() wg.Wait() } func TestConcurrentSetUpstreams(t *testing.T) { dnsHandleFunc("test.site.", resolveToIP(testipv4, testipv6, "dns.test.site.")) server, errch := serveDNS(t, "127.0.0.1:0") defer func() { if err := <-errch; err != nil { t.Errorf("server error: %v", err) } }() if server == nil { return } defer server.Shutdown() r := NewResolver(ResolverConfig{Logf: t.Logf, Forward: true}) r.SetMap(dnsMap) if err := r.Start(); err != nil { t.Fatalf("start: %v", err) } defer r.Close() packet := dnspacket("test.site.", dns.TypeA) // This is purely to ensure that delegation does not race with SetUpstreams. var wg sync.WaitGroup wg.Add(2) go func() { defer wg.Done() r.SetUpstreams([]net.Addr{server.PacketConn.LocalAddr()}) }() go func() { defer wg.Done() syncRespond(r, packet) }() wg.Wait() } var allResponse = []byte{ 0x00, 0x00, // transaction id: 0 0x84, 0x00, // flags: response, authoritative, no error 0x00, 0x01, // one question 0x00, 0x01, // one answer 0x00, 0x00, 0x00, 0x00, // no authority or additional RRs // Question: 0x05, 0x74, 0x65, 0x73, 0x74, 0x31, 0x03, 0x69, 0x70, 0x6e, 0x03, 0x64, 0x65, 0x76, 0x00, // name 0x00, 0xff, 0x00, 0x01, // type ALL, class IN // Answer: 0x05, 0x74, 0x65, 0x73, 0x74, 0x31, 0x03, 0x69, 0x70, 0x6e, 0x03, 0x64, 0x65, 0x76, 0x00, // name 0x00, 0x01, 0x00, 0x01, // type A, class IN 0x00, 0x00, 0x02, 0x58, // TTL: 600 0x00, 0x04, // length: 4 bytes 0x01, 0x02, 0x03, 0x04, // A: 1.2.3.4 } var ipv4Response = []byte{ 0x00, 0x00, // transaction id: 0 0x84, 0x00, // flags: response, authoritative, no error 0x00, 0x01, // one question 0x00, 0x01, // one answer 0x00, 0x00, 0x00, 0x00, // no authority or additional RRs // Question: 0x05, 0x74, 0x65, 0x73, 0x74, 0x31, 0x03, 0x69, 0x70, 0x6e, 0x03, 0x64, 0x65, 0x76, 0x00, // name 0x00, 0x01, 0x00, 0x01, // type A, class IN // Answer: 0x05, 0x74, 0x65, 0x73, 0x74, 0x31, 0x03, 0x69, 0x70, 0x6e, 0x03, 0x64, 0x65, 0x76, 0x00, // name 0x00, 0x01, 0x00, 0x01, // type A, class IN 0x00, 0x00, 0x02, 0x58, // TTL: 600 0x00, 0x04, // length: 4 bytes 0x01, 0x02, 0x03, 0x04, // A: 1.2.3.4 } var ipv6Response = []byte{ 0x00, 0x00, // transaction id: 0 0x84, 0x00, // flags: response, authoritative, no error 0x00, 0x01, // one question 0x00, 0x01, // one answer 0x00, 0x00, 0x00, 0x00, // no authority or additional RRs // Question: 0x05, 0x74, 0x65, 0x73, 0x74, 0x32, 0x03, 0x69, 0x70, 0x6e, 0x03, 0x64, 0x65, 0x76, 0x00, // name 0x00, 0x1c, 0x00, 0x01, // type AAAA, class IN // Answer: 0x05, 0x74, 0x65, 0x73, 0x74, 0x32, 0x03, 0x69, 0x70, 0x6e, 0x03, 0x64, 0x65, 0x76, 0x00, // name 0x00, 0x1c, 0x00, 0x01, // type AAAA, class IN 0x00, 0x00, 0x02, 0x58, // TTL: 600 0x00, 0x10, // length: 16 bytes // AAAA: 0001:0203:0405:0607:0809:0A0B:0C0D:0E0F 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0xb, 0xc, 0xd, 0xe, 0xf, } var ipv4UppercaseResponse = []byte{ 0x00, 0x00, // transaction id: 0 0x84, 0x00, // flags: response, authoritative, no error 0x00, 0x01, // one question 0x00, 0x01, // one answer 0x00, 0x00, 0x00, 0x00, // no authority or additional RRs // Question: 0x05, 0x54, 0x45, 0x53, 0x54, 0x31, 0x03, 0x49, 0x50, 0x4e, 0x03, 0x44, 0x45, 0x56, 0x00, // name 0x00, 0x01, 0x00, 0x01, // type A, class IN // Answer: 0x05, 0x54, 0x45, 0x53, 0x54, 0x31, 0x03, 0x49, 0x50, 0x4e, 0x03, 0x44, 0x45, 0x56, 0x00, // name 0x00, 0x01, 0x00, 0x01, // type A, class IN 0x00, 0x00, 0x02, 0x58, // TTL: 600 0x00, 0x04, // length: 4 bytes 0x01, 0x02, 0x03, 0x04, // A: 1.2.3.4 } var ptrResponse = []byte{ 0x00, 0x00, // transaction id: 0 0x84, 0x00, // flags: response, authoritative, no error 0x00, 0x01, // one question 0x00, 0x01, // one answer 0x00, 0x00, 0x00, 0x00, // no authority or additional RRs // Question: 4.3.2.1.in-addr.arpa 0x01, 0x34, 0x01, 0x33, 0x01, 0x32, 0x01, 0x31, 0x07, 0x69, 0x6e, 0x2d, 0x61, 0x64, 0x64, 0x72, 0x04, 0x61, 0x72, 0x70, 0x61, 0x00, 0x00, 0x0c, 0x00, 0x01, // type PTR, class IN // Answer: 4.3.2.1.in-addr.arpa 0x01, 0x34, 0x01, 0x33, 0x01, 0x32, 0x01, 0x31, 0x07, 0x69, 0x6e, 0x2d, 0x61, 0x64, 0x64, 0x72, 0x04, 0x61, 0x72, 0x70, 0x61, 0x00, 0x00, 0x0c, 0x00, 0x01, // type PTR, class IN 0x00, 0x00, 0x02, 0x58, // TTL: 600 0x00, 0x0f, // length: 15 bytes // PTR: test1.ipn.dev 0x05, 0x74, 0x65, 0x73, 0x74, 0x31, 0x03, 0x69, 0x70, 0x6e, 0x03, 0x64, 0x65, 0x76, 0x00, } var ptrResponse6 = []byte{ 0x00, 0x00, // transaction id: 0 0x84, 0x00, // flags: response, authoritative, no error 0x00, 0x01, // one question 0x00, 0x01, // one answer 0x00, 0x00, 0x00, 0x00, // no authority or additional RRs // Question: f.0.e.0.d.0.c.0.b.0.a.0.9.0.8.0.7.0.6.0.5.0.4.0.3.0.2.0.1.0.0.0.ip6.arpa 0x01, 0x66, 0x01, 0x30, 0x01, 0x65, 0x01, 0x30, 0x01, 0x64, 0x01, 0x30, 0x01, 0x63, 0x01, 0x30, 0x01, 0x62, 0x01, 0x30, 0x01, 0x61, 0x01, 0x30, 0x01, 0x39, 0x01, 0x30, 0x01, 0x38, 0x01, 0x30, 0x01, 0x37, 0x01, 0x30, 0x01, 0x36, 0x01, 0x30, 0x01, 0x35, 0x01, 0x30, 0x01, 0x34, 0x01, 0x30, 0x01, 0x33, 0x01, 0x30, 0x01, 0x32, 0x01, 0x30, 0x01, 0x31, 0x01, 0x30, 0x01, 0x30, 0x01, 0x30, 0x03, 0x69, 0x70, 0x36, 0x04, 0x61, 0x72, 0x70, 0x61, 0x00, 0x00, 0x0c, 0x00, 0x01, // type PTR, class IN6 // Answer: f.0.e.0.d.0.c.0.b.0.a.0.9.0.8.0.7.0.6.0.5.0.4.0.3.0.2.0.1.0.0.0.ip6.arpa 0x01, 0x66, 0x01, 0x30, 0x01, 0x65, 0x01, 0x30, 0x01, 0x64, 0x01, 0x30, 0x01, 0x63, 0x01, 0x30, 0x01, 0x62, 0x01, 0x30, 0x01, 0x61, 0x01, 0x30, 0x01, 0x39, 0x01, 0x30, 0x01, 0x38, 0x01, 0x30, 0x01, 0x37, 0x01, 0x30, 0x01, 0x36, 0x01, 0x30, 0x01, 0x35, 0x01, 0x30, 0x01, 0x34, 0x01, 0x30, 0x01, 0x33, 0x01, 0x30, 0x01, 0x32, 0x01, 0x30, 0x01, 0x31, 0x01, 0x30, 0x01, 0x30, 0x01, 0x30, 0x03, 0x69, 0x70, 0x36, 0x04, 0x61, 0x72, 0x70, 0x61, 0x00, 0x00, 0x0c, 0x00, 0x01, // type PTR, class IN 0x00, 0x00, 0x02, 0x58, // TTL: 600 0x00, 0x0f, // length: 15 bytes // PTR: test2.ipn.dev 0x05, 0x74, 0x65, 0x73, 0x74, 0x32, 0x03, 0x69, 0x70, 0x6e, 0x03, 0x64, 0x65, 0x76, 0x00, } var nxdomainResponse = []byte{ 0x00, 0x00, // transaction id: 0 0x84, 0x03, // flags: response, authoritative, error: nxdomain 0x00, 0x01, // one question 0x00, 0x00, // no answers 0x00, 0x00, 0x00, 0x00, // no authority or additional RRs // Question: 0x05, 0x74, 0x65, 0x73, 0x74, 0x33, 0x03, 0x69, 0x70, 0x6e, 0x03, 0x64, 0x65, 0x76, 0x00, // name 0x00, 0x01, 0x00, 0x01, // type A, class IN } var emptyResponse = []byte{ 0x00, 0x00, // transaction id: 0 0x84, 0x00, // flags: response, authoritative, no error 0x00, 0x01, // one question 0x00, 0x00, // no answers 0x00, 0x00, 0x00, 0x00, // no authority or additional RRs // Question: 0x05, 0x74, 0x65, 0x73, 0x74, 0x31, 0x03, 0x69, 0x70, 0x6e, 0x03, 0x64, 0x65, 0x76, 0x00, // name 0x00, 0x1c, 0x00, 0x01, // type AAAA, class IN } func TestFull(t *testing.T) { r := NewResolver(ResolverConfig{Logf: t.Logf, Forward: false}) r.SetMap(dnsMap) if err := r.Start(); err != nil { t.Fatalf("start: %v", err) } defer r.Close() // One full packet and one error packet tests := []struct { name string request []byte response []byte }{ {"all", dnspacket("test1.ipn.dev.", dns.TypeALL), allResponse}, {"ipv4", dnspacket("test1.ipn.dev.", dns.TypeA), ipv4Response}, {"ipv6", dnspacket("test2.ipn.dev.", dns.TypeAAAA), ipv6Response}, {"no-ipv6", dnspacket("test1.ipn.dev.", dns.TypeAAAA), emptyResponse}, {"upper", dnspacket("TEST1.IPN.DEV.", dns.TypeA), ipv4UppercaseResponse}, {"ptr", dnspacket("4.3.2.1.in-addr.arpa.", dns.TypePTR), ptrResponse}, {"ptr", dnspacket("f.0.e.0.d.0.c.0.b.0.a.0.9.0.8.0.7.0.6.0.5.0.4.0.3.0.2.0.1.0.0.0.ip6.arpa.", dns.TypePTR), ptrResponse6}, {"nxdomain", dnspacket("test3.ipn.dev.", dns.TypeA), nxdomainResponse}, } for _, tt := range tests { t.Run(tt.name, func(t *testing.T) { response, err := syncRespond(r, tt.request) if err != nil { t.Errorf("err = %v; want nil", err) } if !bytes.Equal(response, tt.response) { t.Errorf("response = %x; want %x", response, tt.response) } }) } } func TestAllocs(t *testing.T) { r := NewResolver(ResolverConfig{Logf: t.Logf, Forward: false}) r.SetMap(dnsMap) if err := r.Start(); err != nil { t.Fatalf("start: %v", err) } defer r.Close() // It is seemingly pointless to test allocs in the delegate path, // as dialer.Dial -> Read -> Write alone comprise 12 allocs. tests := []struct { name string query []byte want int }{ // Name lowercasing and response slice created by dns.NewBuilder. {"forward", dnspacket("test1.ipn.dev.", dns.TypeA), 2}, // 3 extra allocs in rdnsNameToIPv4 and one in marshalPTRRecord (dns.NewName). {"reverse", dnspacket("4.3.2.1.in-addr.arpa.", dns.TypePTR), 5}, } for _, tt := range tests { allocs := testing.AllocsPerRun(100, func() { syncRespond(r, tt.query) }) if int(allocs) > tt.want { t.Errorf("%s: allocs = %v; want %v", tt.name, allocs, tt.want) } } } func TestTrimRDNSBonjourPrefix(t *testing.T) { tests := []struct { in string want bool }{ {"b._dns-sd._udp.0.10.20.172.in-addr.arpa.", true}, {"db._dns-sd._udp.0.10.20.172.in-addr.arpa.", true}, {"r._dns-sd._udp.0.10.20.172.in-addr.arpa.", true}, {"dr._dns-sd._udp.0.10.20.172.in-addr.arpa.", true}, {"lb._dns-sd._udp.0.10.20.172.in-addr.arpa.", true}, {"qq._dns-sd._udp.0.10.20.172.in-addr.arpa.", false}, {"0.10.20.172.in-addr.arpa.", false}, {"i-have-no-dot", false}, } for _, test := range tests { got := hasRDNSBonjourPrefix(test.in) if got != test.want { t.Errorf("trimRDNSBonjourPrefix(%q) = %v, want %v", test.in, got, test.want) } } } func BenchmarkFull(b *testing.B) { dnsHandleFunc("test.site.", resolveToIP(testipv4, testipv6, "dns.test.site.")) server, errch := serveDNS(b, "127.0.0.1:0") defer func() { if err := <-errch; err != nil { b.Errorf("server error: %v", err) } }() if server == nil { return } defer server.Shutdown() r := NewResolver(ResolverConfig{Logf: b.Logf, Forward: true}) r.SetMap(dnsMap) r.SetUpstreams([]net.Addr{server.PacketConn.LocalAddr()}) if err := r.Start(); err != nil { b.Fatalf("start: %v", err) } defer r.Close() tests := []struct { name string request []byte }{ {"forward", dnspacket("test1.ipn.dev.", dns.TypeA)}, {"reverse", dnspacket("4.3.2.1.in-addr.arpa.", dns.TypePTR)}, {"delegated", dnspacket("test.site.", dns.TypeA)}, } for _, tt := range tests { b.Run(tt.name, func(b *testing.B) { for i := 0; i < b.N; i++ { syncRespond(r, tt.request) } }) } } func TestMarshalResponseFormatError(t *testing.T) { resp := new(response) resp.Header.RCode = dns.RCodeFormatError v, err := marshalResponse(resp) if err != nil { t.Errorf("marshal error: %v", err) } t.Logf("response: %q", v) }