plugin/rewrite: handle continue in response rewrite (#1740)

* handle continue in response rewrite

* add test

plugin/rewrite/reverter_test.go

@@ -11,19 +11,14 @@ import (
 	"github.com/miekg/dns"
 )
 
-func TestResponseReverter(t *testing.T) {
-	rules := []Rule{}
-	r, _ := newNameRule("stop", "regex", `(core)\.(dns)\.(rocks)`, "{2}.{1}.{3}", "answer", "name", `(dns)\.(core)\.(rocks)`, "{2}.{1}.{3}")
-	rules = append(rules, r)
-
-	tests := []struct {
+var tests = []struct {
 	from     string
 	fromType uint16
 	answer   []dns.RR
 	to       string
 	toType   uint16
 	noRevert bool
-	}{
+}{
 	{"core.dns.rocks", dns.TypeA, []dns.RR{test.A("dns.core.rocks.  5   IN  A  10.0.0.1")}, "core.dns.rocks", dns.TypeA, false},
 	{"core.dns.rocks", dns.TypeSRV, []dns.RR{test.SRV("dns.core.rocks.  5  IN  SRV 0 100 100 srv1.dns.core.rocks.")}, "core.dns.rocks", dns.TypeSRV, false},
 	{"core.dns.rocks", dns.TypeA, []dns.RR{test.A("core.dns.rocks.  5   IN  A  10.0.0.1")}, "dns.core.rocks.", dns.TypeA, true},
@@ -33,8 +28,24 @@ func TestResponseReverter(t *testing.T) {
 		test.A("dns.core.rocks.  5   IN  A  10.0.0.1"),
 		test.A("dns.core.rocks.  5   IN  A  10.0.0.2"),
 	}, "core.dns.rocks", dns.TypeA, false},
-	}
+}
+
+func TestResponseReverter(t *testing.T) {
+
+	rules := []Rule{}
+	r, _ := newNameRule("stop", "regex", `(core)\.(dns)\.(rocks)`, "{2}.{1}.{3}", "answer", "name", `(dns)\.(core)\.(rocks)`, "{2}.{1}.{3}")
+	rules = append(rules, r)
+
+	doReverterTests(rules, t)
+
+	rules = []Rule{}
+	r, _ = newNameRule("continue", "regex", `(core)\.(dns)\.(rocks)`, "{2}.{1}.{3}", "answer", "name", `(dns)\.(core)\.(rocks)`, "{2}.{1}.{3}")
+	rules = append(rules, r)
+
+	doReverterTests(rules, t)
+}
 
+func doReverterTests(rules []Rule, t *testing.T) {
 	ctx := context.TODO()
 	for i, tc := range tests {
 		m := new(dns.Msg)

plugin/rewrite/rewrite.go

@@ -64,7 +64,10 @@ func (rw Rewrite) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg
 			// }
 		}
 	}
+	if rw.noRevert || len(wr.ResponseRules) == 0 {
 		return plugin.NextOrFailure(rw.Name(), rw.Next, ctx, w, r)
+	}
+	return plugin.NextOrFailure(rw.Name(), rw.Next, ctx, wr, r)
 }
 
 // Name implements the Handler interface.