Respond case insensitively to A and SOA requests

dns.go

@@ -104,7 +104,7 @@ func (d *DNSServer) readQuery(m *dns.Msg) {
  m.MsgHdr.Authoritative = authoritative
  if authoritative {
  if m.MsgHdr.Rcode == dns.RcodeNameError {
- m.Answer = append(m.Answer, d.SOA)
+ m.Ns = append(m.Ns, d.SOA)
  }
  }
 
@@ -113,7 +113,7 @@ func (d *DNSServer) readQuery(m *dns.Msg) {
 func (d *DNSServer) getRecord(q dns.Question) ([]dns.RR, error) {
  var rr []dns.RR
  var cnames []dns.RR
- domain, ok := d.Domains[q.Name]
+ domain, ok := d.Domains[strings.ToLower(q.Name)]
  if !ok {
  return rr, fmt.Errorf("No records for domain %s", q.Name)
  }
@@ -133,15 +133,15 @@ func (d *DNSServer) getRecord(q dns.Question) ([]dns.RR, error) {
 
 // answeringForDomain checks if we have any records for a domain
 func (d *DNSServer) answeringForDomain(name string) bool {
- _, ok := d.Domains[name]
+ _, ok := d.Domains[strings.ToLower(name)]
  return ok
 }
 
 func (d *DNSServer) isAuthoritative(q dns.Question) bool {
  if d.answeringForDomain(q.Name) {
  return true
  }
- domainParts := strings.Split(q.Name, ".")
+ domainParts := strings.Split(strings.ToLower(q.Name), ".")
  for i := range domainParts {
  if d.answeringForDomain(strings.Join(domainParts[i:], ".")) {
  return true

dns_test.go

@@ -140,11 +140,11 @@ func TestAuthoritative(t *testing.T) {
  if answer.Rcode != dns.RcodeNameError {
  t.Errorf("Was expecing NXDOMAIN rcode, but got [%s] instead.", dns.RcodeToString[answer.Rcode])
  }
- if len(answer.Answer) != 1 {
- t.Errorf("Was expecting exactly one answer (SOA) for invalid subdomain, but got %d", len(answer.Answer))
+ if len(answer.Ns) != 1 {
+ t.Errorf("Was expecting exactly one answer (SOA) for invalid subdomain, but got %d", len(answer.Ns))
  }
- if answer.Answer[0].Header().Rrtype != dns.TypeSOA {
- t.Errorf("Was expecting SOA record as answer for NXDOMAIN but got [%s]", dns.TypeToString[answer.Answer[0].Header().Rrtype])
+ if answer.Ns[0].Header().Rrtype != dns.TypeSOA {
+ t.Errorf("Was expecting SOA record as answer for NXDOMAIN but got [%s]", dns.TypeToString[answer.Ns[0].Header().Rrtype])
  }
  if !answer.MsgHdr.Authoritative {
  t.Errorf("Was expecting authoritative bit to be set")
@@ -218,3 +218,27 @@ func TestResolveTXT(t *testing.T) {
  }
  }
 }
+
+func TestCaseInsensitiveResolveA(t *testing.T) {
+ resolv := resolver{server: "127.0.0.1:15353"}
+ answer, err := resolv.lookup("aUtH.eXAmpLe.org", dns.TypeA)
+ if err != nil {
+ t.Errorf("%v", err)
+ }
+
+ if len(answer.Answer) == 0 {
+ t.Error("No answer for DNS query")
+ }
+}
+
+func TestCaseInsensitiveResolveSOA(t *testing.T) {
+ resolv := resolver{server: "127.0.0.1:15353"}
+ answer, _ := resolv.lookup("doesnotexist.aUtH.eXAmpLe.org", dns.TypeSOA)
+ if answer.Rcode != dns.RcodeNameError {
+ t.Errorf("Was expecing NXDOMAIN rcode, but got [%s] instead.", dns.RcodeToString[answer.Rcode])
+ }
+
+ if len(answer.Ns) == 0 {
+ t.Error("No SOA answer for DNS query")
+ }
+}