reimplement-recursive-resolver #6
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@ -70,11 +70,12 @@ func (h *DnsHandler) recursiveResolve(domain string, qtype uint16, maxDepth int)
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answers = append(answers, cname)
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cnameRecursive, cnameAuth, err := h.resolveDNS(record.Content, qtype, maxDepth-1)
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authoritative = authoritative && cnameAuth
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if err != nil {
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log.Println(err)
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return nil, authoritative, err
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}
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authoritative = authoritative && cnameAuth
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answers = append(answers, cnameRecursive...)
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}
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@ -126,14 +127,16 @@ func (h *DnsHandler) resolveDNS(domain string, qtype uint16, maxDepth int) ([]dn
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continue
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}
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cnameAnswers, _, err := h.resolveDNS(cname.Target, qtype, maxDepth-1)
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cnameAnswers, cnameAuth, err := h.resolveDNS(cname.Target, qtype, maxDepth-1)
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authoritative = authoritative && cnameAuth
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if err != nil {
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return nil, false, err
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}
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answers = append(answers, cnameAnswers...)
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}
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return answers, false, nil
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authoritative = authoritative && len(externalAnswers) == 0
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return answers, authoritative, nil
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}
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func (h *DnsHandler) ServeDNS(w dns.ResponseWriter, r *dns.Msg) {
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@ -58,83 +58,6 @@ func setup(arguments *args.Arguments) (*sql.DB, *dns.Server, string, func()) {
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}
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}
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func TestWhenExternalDomain(t *testing.T) {
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externalDb, _, externalAddr, externalCleanup := setup(nil)
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internalDb, _, internalAddr, internalCleanup := setup(&args.Arguments{
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DnsPort: randomPort(),
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DnsResolvers: []string{externalAddr},
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})
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defer internalCleanup()
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defer externalCleanup()
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authoritativeRecords := []database.DNSRecord{
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{
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ID: "1",
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UserID: "test",
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Name: "external.example.com.",
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Type: "CNAME",
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Content: "external.internal.example.com.",
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},
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}
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internalRecords := []database.DNSRecord{
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{
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ID: "1",
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UserID: "test",
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Name: "external.internal.example.com.",
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Type: "A",
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Content: "127.0.0.1",
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},
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{
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ID: "2",
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UserID: "test",
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Name: "test.internal.example.com.",
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Type: "CNAME",
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Content: "external.example.com.",
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},
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}
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for _, record := range authoritativeRecords {
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database.SaveDNSRecord(externalDb, &record)
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}
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for _, record := range internalRecords {
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database.SaveDNSRecord(internalDb, &record)
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}
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// ensure that if the record doesn't exist in the internal database, it will
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// go and query the external dns resolvers, then loop back to the internal
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qtype := dns.TypeA
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domain := dns.Fqdn("test.internal.example.com.")
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client := &dns.Client{}
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message := &dns.Msg{}
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message.SetQuestion(domain, qtype)
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in, _, err := client.Exchange(message, internalAddr)
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if err != nil {
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t.Fatal(err)
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}
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if len(in.Answer) != 3 {
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t.Fatalf("expected 3 answers, got %d", len(in.Answer))
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}
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aRecord := in.Answer[2]
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if aRecord.Header().Name != internalRecords[0].Name {
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t.Fatalf("expected %s, got %s", domain, aRecord.Header().Name)
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}
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if aRecord.Header().Rrtype != dns.TypeA {
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t.Fatalf("expected %s, got %s", dns.TypeToString[aRecord.Header().Rrtype], internalRecords[1].Type)
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}
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if aRecord.(*dns.A).A.String() != internalRecords[0].Content {
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t.Fatalf("expected %s, got %s", internalRecords[0].Content, aRecord.(*dns.A).A.String())
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}
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if in.Authoritative {
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t.Fatalf("expected non-authoritative response")
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}
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}
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func TestWhenCNAMEIsResolved(t *testing.T) {
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testDb, _, addr, cleanup := setup(nil)
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defer cleanup()
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@ -322,3 +245,86 @@ func TestWhenUnresolvingCNAMEWithMaxDepth(t *testing.T) {
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t.Fatalf("expected SERVFAIL, got %d", in.Rcode)
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}
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}
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func TestWhenExternalDomain(t *testing.T) {
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externalDb, _, externalAddr, externalCleanup := setup(nil)
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internalDb, _, internalAddr, internalCleanup := setup(&args.Arguments{
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DnsPort: randomPort(),
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DnsResolvers: []string{externalAddr},
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})
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defer internalCleanup()
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defer externalCleanup()
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authoritativeRecords := []database.DNSRecord{
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{
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ID: "1",
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UserID: "test",
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Name: "external.example.com.",
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Type: "CNAME",
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Content: "external.internal.example.com.",
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},
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{
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ID: "2",
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UserID: "test",
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Name: "final.example.com.",
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Type: "A",
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Content: "127.0.0.1",
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},
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}
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internalRecords := []database.DNSRecord{
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{
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ID: "1",
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UserID: "test",
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Name: "external.internal.example.com.",
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Type: "CNAME",
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Content: "final.example.com",
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},
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{
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ID: "2",
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UserID: "test",
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Name: "test.internal.example.com.",
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Type: "CNAME",
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Content: "external.example.com.",
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},
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}
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for _, record := range authoritativeRecords {
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database.SaveDNSRecord(externalDb, &record)
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}
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for _, record := range internalRecords {
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database.SaveDNSRecord(internalDb, &record)
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}
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// ensure that if the record doesn't exist in the internal database, it will
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// go and query the external dns resolvers, then loop back to the internal
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qtype := dns.TypeA
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domain := dns.Fqdn("test.internal.example.com.")
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client := &dns.Client{}
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message := &dns.Msg{}
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message.SetQuestion(domain, qtype)
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in, _, err := client.Exchange(message, internalAddr)
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if err != nil {
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t.Fatal(err)
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}
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if len(in.Answer) != 4 {
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t.Fatalf("expected 4 answers, got %d", len(in.Answer))
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}
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aRecord := in.Answer[3]
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if aRecord.Header().Name != authoritativeRecords[1].Name {
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t.Fatalf("expected %s, got %s", domain, aRecord.Header().Name)
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}
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if aRecord.Header().Rrtype != dns.TypeA {
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t.Fatalf("expected %s, got %s", dns.TypeToString[aRecord.Header().Rrtype], internalRecords[1].Type)
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}
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if aRecord.(*dns.A).A.String() != authoritativeRecords[1].Content {
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t.Fatalf("expected %s, got %s", authoritativeRecords[1].Content, aRecord.(*dns.A).A.String())
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}
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if in.Authoritative {
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t.Fatalf("expected non-authoritative response")
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}
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}
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Loading…
Reference in New Issue