func dnsHandler(w dns.ResponseWriter, r *dns.Msg) { defer w.Close() m := new(dns.Msg) m.SetReply(r) m.Compress = false for _, q := range r.Question { fmt.Printf("dns-srv: Query -- [%s] %s\n", q.Name, dns.TypeToString[q.Qtype]) switch q.Qtype { case dns.TypeA: record := new(dns.A) record.Hdr = dns.RR_Header{ Name: q.Name, Rrtype: dns.TypeA, Class: dns.ClassINET, Ttl: 0, } record.A = net.ParseIP("127.0.0.1") m.Answer = append(m.Answer, record) case dns.TypeMX: record := new(dns.MX) record.Hdr = dns.RR_Header{ Name: q.Name, Rrtype: dns.TypeMX, Class: dns.ClassINET, Ttl: 0, } record.Mx = "mail." + q.Name record.Preference = 10 m.Answer = append(m.Answer, record) } } w.WriteMsg(m) return }
func (ts *testSrv) dnsHandler(w dns.ResponseWriter, r *dns.Msg) { m := new(dns.Msg) m.SetReply(r) m.Compress = false // Normally this test DNS server will return 127.0.0.1 for everything. // However, in some situations (for instance Docker), it's useful to return a // different hardcoded host. You can do so by setting the FAKE_DNS environment // variable. fakeDNS := os.Getenv("FAKE_DNS") if fakeDNS == "" { fakeDNS = "127.0.0.1" } for _, q := range r.Question { fmt.Printf("dns-srv: Query -- [%s] %s\n", q.Name, dns.TypeToString[q.Qtype]) switch q.Qtype { case dns.TypeA: record := new(dns.A) record.Hdr = dns.RR_Header{ Name: q.Name, Rrtype: dns.TypeA, Class: dns.ClassINET, Ttl: 0, } record.A = net.ParseIP(fakeDNS) m.Answer = append(m.Answer, record) case dns.TypeMX: record := new(dns.MX) record.Hdr = dns.RR_Header{ Name: q.Name, Rrtype: dns.TypeMX, Class: dns.ClassINET, Ttl: 0, } record.Mx = "mail." + q.Name record.Preference = 10 m.Answer = append(m.Answer, record) case dns.TypeTXT: ts.mu.RLock() value, present := ts.txtRecords[q.Name] ts.mu.RUnlock() if !present { continue } record := new(dns.TXT) record.Hdr = dns.RR_Header{ Name: q.Name, Rrtype: dns.TypeTXT, Class: dns.ClassINET, Ttl: 0, } record.Txt = []string{value} m.Answer = append(m.Answer, record) case dns.TypeCAA: if q.Name == "bad-caa-reserved.com." || q.Name == "good-caa-reserved.com." { record := new(dns.CAA) record.Hdr = dns.RR_Header{ Name: q.Name, Rrtype: dns.TypeCAA, Class: dns.ClassINET, Ttl: 0, } record.Tag = "issue" if q.Name == "bad-caa-reserved.com." { record.Value = "sad-hacker-ca.invalid" } else if q.Name == "good-caa-reserved.com." { record.Value = "happy-hacker-ca.invalid" } m.Answer = append(m.Answer, record) } } } auth := new(dns.SOA) auth.Hdr = dns.RR_Header{Name: "boulder.invalid.", Rrtype: dns.TypeSOA, Class: dns.ClassINET, Ttl: 0} auth.Ns = "ns.boulder.invalid." auth.Mbox = "master.boulder.invalid." auth.Serial = 1 auth.Refresh = 1 auth.Retry = 1 auth.Expire = 1 auth.Minttl = 1 m.Ns = append(m.Ns, auth) w.WriteMsg(m) return }