diff --git a/osbase/net/dns/testhelpers.go b/osbase/net/dns/testhelpers.go
new file mode 100644
index 0000000..b8943fd
--- /dev/null
+++ b/osbase/net/dns/testhelpers.go
@@ -0,0 +1,68 @@
+package dns
+
+import (
+	"errors"
+	"fmt"
+	"net"
+
+	"github.com/miekg/dns"
+)
+
+// CreateTestRequest creates a Request for use in tests.
+func CreateTestRequest(qname string, qtype uint16, proto string) *Request {
+	var addr net.Addr
+	switch proto {
+	case "udp":
+		addr = &net.UDPAddr{}
+	case "tcp":
+		addr = &net.TCPAddr{}
+	default:
+		panic(fmt.Sprintf("Unknown protocol %q", proto))
+	}
+	req := &Request{
+		Reply:          new(dns.Msg),
+		Writer:         &testWriter{addr: addr},
+		Qopt:           &dns.OPT{Hdr: dns.RR_Header{Name: ".", Rrtype: dns.TypeOPT}},
+		Ropt:           &dns.OPT{Hdr: dns.RR_Header{Name: ".", Rrtype: dns.TypeOPT}},
+		Qname:          qname,
+		QnameCanonical: dns.CanonicalName(qname),
+		Qtype:          qtype,
+	}
+	req.Reply.Response = true
+	req.Reply.Question = []dns.Question{{
+		Name:   qname,
+		Qtype:  qtype,
+		Qclass: dns.ClassINET,
+	}}
+	req.Reply.RecursionAvailable = true
+	req.Reply.RecursionDesired = true
+	req.Qopt.SetUDPSize(advertiseUDPSize)
+	req.Ropt.SetUDPSize(advertiseUDPSize)
+	return req
+}
+
+type testWriter struct {
+	addr net.Addr
+	msg  *dns.Msg
+}
+
+func (t *testWriter) LocalAddr() net.Addr  { return t.addr }
+func (t *testWriter) RemoteAddr() net.Addr { return t.addr }
+func (*testWriter) Write([]byte) (int, error) {
+	return 0, errors.New("testWriter only supports WriteMsg")
+}
+func (*testWriter) Close() error        { return nil }
+func (*testWriter) TsigStatus() error   { return nil }
+func (*testWriter) TsigTimersOnly(bool) {}
+func (*testWriter) Hijack()             {}
+
+func (t *testWriter) WriteMsg(msg *dns.Msg) error {
+	if msg == nil {
+		panic("WriteMsg(nil)")
+	}
+	if t.msg != nil {
+		panic("duplicate WriteMsg()")
+	}
+	t.msg = msg
+	return nil
+}