Merge pull request #1277 from weaveworks/1275-negative-dns

Return NXDOMAIN when we don't have entries

and drop the non-authoritative special case for recursive dns.

Fixes #1275.

nameserver/dns.go

@@ -134,6 +134,10 @@ func (d *DNSServer) handleLocal(defaultMaxResponseSize int) func(dns.ResponseWri
 		}
 
 		addrs := d.ns.Lookup(hostname)
+		if len(addrs) == 0 {
+			d.errorResponse(req, dns.RcodeNameError, w)
+			return
+		}
 
 		response := dns.Msg{}
 		response.RecursionAvailable = true
@@ -233,12 +237,8 @@ func (d *DNSServer) handleRecursive(client *dns.Client, defaultMaxResponseSize i
 				d.ns.debugf("error trying %s: %v", server, err)
 				continue
 			}
-			if response.Rcode != dns.RcodeSuccess && !response.Authoritative {
-				d.ns.debugf("non-authoritative error trying %s: %v", server, response.Rcode)
-				continue
-			}
 			d.ns.debugf("response: %+v", response)
-			response.SetReply(req)
+			response.Id = req.Id
 			if err := w.WriteMsg(response); err != nil {
 				d.ns.infof("error responding: %v", err)
 			}

test/250_dns_lookup_2_test.sh

@@ -1,16 +0,0 @@
-#! /bin/bash
-
-. ./config.sh
-
-C1=10.2.0.78
-
-start_suite "Cross host dns-lookup"
-
-weave_on $HOST1 launch
-weave_on $HOST2 launch $HOST1
-
-start_container $HOST1 $C1/24 --name c1
-
-assert "weave_on $HOST2 dns-lookup c1" $C1
-
-end_suite

test/250_dns_negative_test.sh

@@ -0,0 +1,12 @@
+#! /bin/bash
+
+. ./config.sh
+
+start_suite "Negative DNS queries"
+
+weave_on $HOST1 launch
+start_container_with_dns $HOST1 --name c1
+assert_raises "exec_on $HOST1 c1 dig A foo.weave.local | grep 'status: NXDOMAIN'"
+assert_raises "exec_on $HOST1 c1 dig A foo.invalid | grep 'status: NXDOMAIN'"
+
+end_suite