Implement external lookups for CNAMEs

middleware/auto/auto.go

@@ -34,7 +34,7 @@ type (
 		// In the future this should be something like ZoneMeta that contains all this stuff.
 		transferTo []string
 		noReload   bool
-		Proxy      proxy.Proxy // Proxy for looking up names during the resolution process
+		proxy      proxy.Proxy // Proxy for looking up names during the resolution process
 
 		duration time.Duration
 	}

middleware/auto/setup.go

@@ -155,7 +155,7 @@ func autoParse(c *caddy.Controller) (Auto, error) {
 							args[i] = h + ":53"
 						}
 					}
-					a.loader.Proxy = proxy.New(args)
+					a.loader.proxy = proxy.New(args)
 
 				default:
 					t, _, e := file.TransferParse(c, false)

middleware/auto/walk.go

@@ -51,6 +51,7 @@ func (a Auto) Walk() error {
 		}
 
 		zo.NoReload = a.loader.noReload
+		zo.Proxy = a.loader.proxy
 		zo.TransferTo = a.loader.transferTo
 
 		a.Zones.Add(zo, origin)

middleware/file/cname_test.go

@@ -93,7 +93,7 @@ func TestLookupCNAMEExternal(t *testing.T) {
 	if err != nil {
 		t.Fatalf("Expected no error when reading zone, got %q", err)
 	}
-	zone.Proxy = proxy.New([]string{"8.8.8.8:53"}) // TODO(point to local instance)
+	zone.Proxy = proxy.New([]string{"8.8.8.8:53"}) // TODO(miek): point to local instance
 
 	fm := File{Next: test.ErrorHandler(), Zones: Zones{Z: map[string]*Zone{name: zone}, Names: []string{name}}}
 	ctx := context.TODO()

middleware/file/file.go

@@ -84,7 +84,7 @@ func (f File) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg) (i
 		return xfr.ServeDNS(ctx, w, r)
 	}
 
-	answer, ns, extra, result := z.Lookup(qname, state.QType(), state.Do())
+	answer, ns, extra, result := z.Lookup(state, qname)
 
 	m := new(dns.Msg)
 	m.SetReply(r)

middleware/file/lookup.go

@@ -25,7 +25,11 @@ const (
 
 // Lookup looks up qname and qtype in the zone. When do is true DNSSEC records are included.
 // Three sets of records are returned, one for the answer, one for authority  and one for the additional section.
-func (z *Zone) Lookup(qname string, qtype uint16, do bool) ([]dns.RR, []dns.RR, []dns.RR, Result) {
+func (z *Zone) Lookup(state request.Request, qname string) ([]dns.RR, []dns.RR, []dns.RR, Result) {
+
+	qtype := state.QType()
+	do := state.Do()
+
 	if !z.NoReload {
 		z.reloadMu.RLock()
 	}
@@ -121,7 +125,7 @@ func (z *Zone) Lookup(qname string, qtype uint16, do bool) ([]dns.RR, []dns.RR,
 
 		// DNAME...?
 		if rrs := elem.Types(dns.TypeCNAME); len(rrs) > 0 && qtype != dns.TypeCNAME {
-			return z.searchCNAME(elem, rrs, qtype, do)
+			return z.searchCNAME(state, elem, rrs)
 		}
 
 		rrs := elem.Types(qtype, qname)
@@ -153,7 +157,7 @@ func (z *Zone) Lookup(qname string, qtype uint16, do bool) ([]dns.RR, []dns.RR,
 		auth := []dns.RR{}
 
 		if rrs := wildElem.Types(dns.TypeCNAME, qname); len(rrs) > 0 {
-			return z.searchCNAME(wildElem, rrs, qtype, do)
+			return z.searchCNAME(state, wildElem, rrs)
 		}
 
 		rrs := wildElem.Types(qtype, qname)
@@ -252,7 +256,11 @@ func (z *Zone) ns(do bool) []dns.RR {
 	return z.Apex.NS
 }
 
-func (z *Zone) searchCNAME(elem *tree.Elem, rrs []dns.RR, qtype uint16, do bool) ([]dns.RR, []dns.RR, []dns.RR, Result) {
+func (z *Zone) searchCNAME(state request.Request, elem *tree.Elem, rrs []dns.RR) ([]dns.RR, []dns.RR, []dns.RR, Result) {
+
+	qtype := state.QType()
+	do := state.Do()
+
 	if do {
 		sigs := elem.Types(dns.TypeRRSIG)
 		sigs = signatureForSubType(sigs, dns.TypeCNAME)
@@ -263,14 +271,10 @@ func (z *Zone) searchCNAME(elem *tree.Elem, rrs []dns.RR, qtype uint16, do bool)
 
 	targetName := rrs[0].(*dns.CNAME).Target
 	elem, _ = z.Tree.Search(targetName)
-	println(targetName)
 	if elem == nil {
 		if !dns.IsSubDomain(z.origin, targetName) {
-			println(targetName, "is not a child of", z.origin)
+			rrs = append(rrs, z.externalLookup(state, targetName, qtype)...)
 		}
-		st := request.Request{}
-		z.Proxy.Lookup(st, targetName, qtype)
-
 		return rrs, nil, nil, Success
 	}
 
@@ -292,7 +296,9 @@ Redo:
 		elem, _ = z.Tree.Search(targetName)
 		if elem == nil {
 			if !dns.IsSubDomain(z.origin, targetName) {
-				println(targetName, "is not a child of", z.origin)
+				if !dns.IsSubDomain(z.origin, targetName) {
+					rrs = append(rrs, z.externalLookup(state, targetName, qtype)...)
+				}
 			}
 			return rrs, nil, nil, Success
 		}
@@ -331,6 +337,15 @@ func cnameForType(targets []dns.RR, origQtype uint16) []dns.RR {
 	return ret
 }
 
+func (z *Zone) externalLookup(state request.Request, target string, qtype uint16) []dns.RR {
+	m, e := z.Proxy.Lookup(state, target, qtype)
+	if e != nil || m == nil {
+		// TODO(miek): debugMsg for this as well? Log?
+		return nil
+	}
+	return m.Answer
+}
+
 // signatureForSubType range through the signature and return the correct ones for the subtype.
 func signatureForSubType(rrs []dns.RR, subtype uint16) []dns.RR {
 	sigs := []dns.RR{}

middleware/file/reload_test.go

@@ -8,6 +8,7 @@ import (
 	"time"
 
 	"github.com/miekg/coredns/middleware/test"
+	"github.com/miekg/coredns/request"
 
 	"github.com/miekg/dns"
 )
@@ -31,11 +32,17 @@ func TestZoneReload(t *testing.T) {
 
 	z.Reload()
 
-	if _, _, _, res := z.Lookup("miek.nl.", dns.TypeSOA, false); res != Success {
+	r := new(dns.Msg)
+	r.SetQuestion("miek.nl", dns.TypeSOA)
+	state := request.Request{W: &test.ResponseWriter{}, Req: r}
+	if _, _, _, res := z.Lookup(state, "miek.nl."); res != Success {
 		t.Fatalf("failed to lookup, got %d", res)
 	}
 
-	if _, _, _, res := z.Lookup("miek.nl.", dns.TypeNS, false); res != Success {
+	r = new(dns.Msg)
+	r.SetQuestion("miek.nl", dns.TypeNS)
+	state = request.Request{W: &test.ResponseWriter{}, Req: r}
+	if _, _, _, res := z.Lookup(state, "miek.nl."); res != Success {
 		t.Fatalf("failed to lookup, got %d", res)
 	}