dns/server_test.go

690 lines
17 KiB
Go

package dns
import (
"crypto/tls"
"fmt"
"io"
"net"
"runtime"
"sync"
"testing"
"time"
)
func HelloServer(w ResponseWriter, req *Msg) {
m := new(Msg)
m.SetReply(req)
m.Extra = make([]RR, 1)
m.Extra[0] = &TXT{Hdr: RR_Header{Name: m.Question[0].Name, Rrtype: TypeTXT, Class: ClassINET, Ttl: 0}, Txt: []string{"Hello world"}}
w.WriteMsg(m)
}
func HelloServerBadID(w ResponseWriter, req *Msg) {
m := new(Msg)
m.SetReply(req)
m.Id++
m.Extra = make([]RR, 1)
m.Extra[0] = &TXT{Hdr: RR_Header{Name: m.Question[0].Name, Rrtype: TypeTXT, Class: ClassINET, Ttl: 0}, Txt: []string{"Hello world"}}
w.WriteMsg(m)
}
func HelloServerEchoAddrPort(w ResponseWriter, req *Msg) {
m := new(Msg)
m.SetReply(req)
remoteAddr := w.RemoteAddr().String()
m.Extra = make([]RR, 1)
m.Extra[0] = &TXT{Hdr: RR_Header{Name: m.Question[0].Name, Rrtype: TypeTXT, Class: ClassINET, Ttl: 0}, Txt: []string{remoteAddr}}
w.WriteMsg(m)
}
func AnotherHelloServer(w ResponseWriter, req *Msg) {
m := new(Msg)
m.SetReply(req)
m.Extra = make([]RR, 1)
m.Extra[0] = &TXT{Hdr: RR_Header{Name: m.Question[0].Name, Rrtype: TypeTXT, Class: ClassINET, Ttl: 0}, Txt: []string{"Hello example"}}
w.WriteMsg(m)
}
func RunLocalUDPServer(laddr string) (*Server, string, error) {
server, l, _, err := RunLocalUDPServerWithFinChan(laddr)
return server, l, err
}
func RunLocalUDPServerWithFinChan(laddr string) (*Server, string, chan struct{}, error) {
pc, err := net.ListenPacket("udp", laddr)
if err != nil {
return nil, "", nil, err
}
server := &Server{PacketConn: pc, ReadTimeout: time.Hour, WriteTimeout: time.Hour}
waitLock := sync.Mutex{}
waitLock.Lock()
server.NotifyStartedFunc = waitLock.Unlock
fin := make(chan struct{}, 0)
go func() {
server.ActivateAndServe()
close(fin)
pc.Close()
}()
waitLock.Lock()
return server, pc.LocalAddr().String(), fin, nil
}
func RunLocalUDPServerUnsafe(laddr string) (*Server, string, error) {
pc, err := net.ListenPacket("udp", laddr)
if err != nil {
return nil, "", err
}
server := &Server{PacketConn: pc, Unsafe: true,
ReadTimeout: time.Hour, WriteTimeout: time.Hour}
waitLock := sync.Mutex{}
waitLock.Lock()
server.NotifyStartedFunc = waitLock.Unlock
go func() {
server.ActivateAndServe()
pc.Close()
}()
waitLock.Lock()
return server, pc.LocalAddr().String(), nil
}
func RunLocalTCPServer(laddr string) (*Server, string, error) {
l, err := net.Listen("tcp", laddr)
if err != nil {
return nil, "", err
}
server := &Server{Listener: l, ReadTimeout: time.Hour, WriteTimeout: time.Hour}
waitLock := sync.Mutex{}
waitLock.Lock()
server.NotifyStartedFunc = waitLock.Unlock
go func() {
server.ActivateAndServe()
l.Close()
}()
waitLock.Lock()
return server, l.Addr().String(), nil
}
func RunLocalTLSServer(laddr string, config *tls.Config) (*Server, string, error) {
l, err := tls.Listen("tcp", laddr, config)
if err != nil {
return nil, "", err
}
server := &Server{Listener: l, ReadTimeout: time.Hour, WriteTimeout: time.Hour}
waitLock := sync.Mutex{}
waitLock.Lock()
server.NotifyStartedFunc = waitLock.Unlock
go func() {
server.ActivateAndServe()
l.Close()
}()
waitLock.Lock()
return server, l.Addr().String(), nil
}
func TestServing(t *testing.T) {
HandleFunc("miek.nl.", HelloServer)
HandleFunc("example.com.", AnotherHelloServer)
defer HandleRemove("miek.nl.")
defer HandleRemove("example.com.")
s, addrstr, err := RunLocalUDPServer(":0")
if err != nil {
t.Fatalf("unable to run test server: %v", err)
}
defer s.Shutdown()
c := new(Client)
m := new(Msg)
m.SetQuestion("miek.nl.", TypeTXT)
r, _, err := c.Exchange(m, addrstr)
if err != nil || len(r.Extra) == 0 {
t.Fatal("failed to exchange miek.nl", err)
}
txt := r.Extra[0].(*TXT).Txt[0]
if txt != "Hello world" {
t.Error("unexpected result for miek.nl", txt, "!= Hello world")
}
m.SetQuestion("example.com.", TypeTXT)
r, _, err = c.Exchange(m, addrstr)
if err != nil {
t.Fatal("failed to exchange example.com", err)
}
txt = r.Extra[0].(*TXT).Txt[0]
if txt != "Hello example" {
t.Error("unexpected result for example.com", txt, "!= Hello example")
}
// Test Mixes cased as noticed by Ask.
m.SetQuestion("eXaMplE.cOm.", TypeTXT)
r, _, err = c.Exchange(m, addrstr)
if err != nil {
t.Error("failed to exchange eXaMplE.cOm", err)
}
txt = r.Extra[0].(*TXT).Txt[0]
if txt != "Hello example" {
t.Error("unexpected result for example.com", txt, "!= Hello example")
}
}
func TestServingTLS(t *testing.T) {
HandleFunc("miek.nl.", HelloServer)
HandleFunc("example.com.", AnotherHelloServer)
defer HandleRemove("miek.nl.")
defer HandleRemove("example.com.")
cert, err := tls.X509KeyPair(CertPEMBlock, KeyPEMBlock)
if err != nil {
t.Fatalf("unable to build certificate: %v", err)
}
config := tls.Config{
Certificates: []tls.Certificate{cert},
}
s, addrstr, err := RunLocalTLSServer(":0", &config)
if err != nil {
t.Fatalf("unable to run test server: %v", err)
}
defer s.Shutdown()
c := new(Client)
c.Net = "tcp-tls"
c.TLSConfig = &tls.Config{
InsecureSkipVerify: true,
}
m := new(Msg)
m.SetQuestion("miek.nl.", TypeTXT)
r, _, err := c.Exchange(m, addrstr)
if err != nil || len(r.Extra) == 0 {
t.Fatal("failed to exchange miek.nl", err)
}
txt := r.Extra[0].(*TXT).Txt[0]
if txt != "Hello world" {
t.Error("unexpected result for miek.nl", txt, "!= Hello world")
}
m.SetQuestion("example.com.", TypeTXT)
r, _, err = c.Exchange(m, addrstr)
if err != nil {
t.Fatal("failed to exchange example.com", err)
}
txt = r.Extra[0].(*TXT).Txt[0]
if txt != "Hello example" {
t.Error("unexpected result for example.com", txt, "!= Hello example")
}
// Test Mixes cased as noticed by Ask.
m.SetQuestion("eXaMplE.cOm.", TypeTXT)
r, _, err = c.Exchange(m, addrstr)
if err != nil {
t.Error("failed to exchange eXaMplE.cOm", err)
}
txt = r.Extra[0].(*TXT).Txt[0]
if txt != "Hello example" {
t.Error("unexpected result for example.com", txt, "!= Hello example")
}
}
func BenchmarkServe(b *testing.B) {
b.StopTimer()
HandleFunc("miek.nl.", HelloServer)
defer HandleRemove("miek.nl.")
a := runtime.GOMAXPROCS(4)
s, addrstr, err := RunLocalUDPServer(":0")
if err != nil {
b.Fatalf("unable to run test server: %v", err)
}
defer s.Shutdown()
c := new(Client)
m := new(Msg)
m.SetQuestion("miek.nl", TypeSOA)
b.StartTimer()
for i := 0; i < b.N; i++ {
c.Exchange(m, addrstr)
}
runtime.GOMAXPROCS(a)
}
func benchmarkServe6(b *testing.B) {
b.StopTimer()
HandleFunc("miek.nl.", HelloServer)
defer HandleRemove("miek.nl.")
a := runtime.GOMAXPROCS(4)
s, addrstr, err := RunLocalUDPServer("[::1]:0")
if err != nil {
b.Fatalf("unable to run test server: %v", err)
}
defer s.Shutdown()
c := new(Client)
m := new(Msg)
m.SetQuestion("miek.nl", TypeSOA)
b.StartTimer()
for i := 0; i < b.N; i++ {
c.Exchange(m, addrstr)
}
runtime.GOMAXPROCS(a)
}
func HelloServerCompress(w ResponseWriter, req *Msg) {
m := new(Msg)
m.SetReply(req)
m.Extra = make([]RR, 1)
m.Extra[0] = &TXT{Hdr: RR_Header{Name: m.Question[0].Name, Rrtype: TypeTXT, Class: ClassINET, Ttl: 0}, Txt: []string{"Hello world"}}
m.Compress = true
w.WriteMsg(m)
}
func BenchmarkServeCompress(b *testing.B) {
b.StopTimer()
HandleFunc("miek.nl.", HelloServerCompress)
defer HandleRemove("miek.nl.")
a := runtime.GOMAXPROCS(4)
s, addrstr, err := RunLocalUDPServer(":0")
if err != nil {
b.Fatalf("unable to run test server: %v", err)
}
defer s.Shutdown()
c := new(Client)
m := new(Msg)
m.SetQuestion("miek.nl", TypeSOA)
b.StartTimer()
for i := 0; i < b.N; i++ {
c.Exchange(m, addrstr)
}
runtime.GOMAXPROCS(a)
}
func TestDotAsCatchAllWildcard(t *testing.T) {
mux := NewServeMux()
mux.Handle(".", HandlerFunc(HelloServer))
mux.Handle("example.com.", HandlerFunc(AnotherHelloServer))
handler := mux.match("www.miek.nl.", TypeTXT)
if handler == nil {
t.Error("wildcard match failed")
}
handler = mux.match("www.example.com.", TypeTXT)
if handler == nil {
t.Error("example.com match failed")
}
handler = mux.match("a.www.example.com.", TypeTXT)
if handler == nil {
t.Error("a.www.example.com match failed")
}
handler = mux.match("boe.", TypeTXT)
if handler == nil {
t.Error("boe. match failed")
}
}
func TestCaseFolding(t *testing.T) {
mux := NewServeMux()
mux.Handle("_udp.example.com.", HandlerFunc(HelloServer))
handler := mux.match("_dns._udp.example.com.", TypeSRV)
if handler == nil {
t.Error("case sensitive characters folded")
}
handler = mux.match("_DNS._UDP.EXAMPLE.COM.", TypeSRV)
if handler == nil {
t.Error("case insensitive characters not folded")
}
}
func TestRootServer(t *testing.T) {
mux := NewServeMux()
mux.Handle(".", HandlerFunc(HelloServer))
handler := mux.match(".", TypeNS)
if handler == nil {
t.Error("root match failed")
}
}
type maxRec struct {
max int
sync.RWMutex
}
var M = new(maxRec)
func HelloServerLargeResponse(resp ResponseWriter, req *Msg) {
m := new(Msg)
m.SetReply(req)
m.Authoritative = true
m1 := 0
M.RLock()
m1 = M.max
M.RUnlock()
for i := 0; i < m1; i++ {
aRec := &A{
Hdr: RR_Header{
Name: req.Question[0].Name,
Rrtype: TypeA,
Class: ClassINET,
Ttl: 0,
},
A: net.ParseIP(fmt.Sprintf("127.0.0.%d", i+1)).To4(),
}
m.Answer = append(m.Answer, aRec)
}
resp.WriteMsg(m)
}
func TestServingLargeResponses(t *testing.T) {
HandleFunc("example.", HelloServerLargeResponse)
defer HandleRemove("example.")
s, addrstr, err := RunLocalUDPServer(":0")
if err != nil {
t.Fatalf("unable to run test server: %v", err)
}
defer s.Shutdown()
// Create request
m := new(Msg)
m.SetQuestion("web.service.example.", TypeANY)
c := new(Client)
c.Net = "udp"
M.Lock()
M.max = 2
M.Unlock()
_, _, err = c.Exchange(m, addrstr)
if err != nil {
t.Errorf("failed to exchange: %v", err)
}
// This must fail
M.Lock()
M.max = 20
M.Unlock()
_, _, err = c.Exchange(m, addrstr)
if err == nil {
t.Error("failed to fail exchange, this should generate packet error")
}
// But this must work again
c.UDPSize = 7000
_, _, err = c.Exchange(m, addrstr)
if err != nil {
t.Errorf("failed to exchange: %v", err)
}
}
func TestServingResponse(t *testing.T) {
if testing.Short() {
t.Skip("skipping test in short mode.")
}
HandleFunc("miek.nl.", HelloServer)
s, addrstr, err := RunLocalUDPServer(":0")
if err != nil {
t.Fatalf("unable to run test server: %v", err)
}
c := new(Client)
m := new(Msg)
m.SetQuestion("miek.nl.", TypeTXT)
m.Response = false
_, _, err = c.Exchange(m, addrstr)
if err != nil {
t.Fatal("failed to exchange", err)
}
m.Response = true
_, _, err = c.Exchange(m, addrstr)
if err == nil {
t.Fatal("exchanged response message")
}
s.Shutdown()
s, addrstr, err = RunLocalUDPServerUnsafe(":0")
if err != nil {
t.Fatalf("unable to run test server: %v", err)
}
defer s.Shutdown()
m.Response = true
_, _, err = c.Exchange(m, addrstr)
if err != nil {
t.Fatal("could exchanged response message in Unsafe mode")
}
}
func TestShutdownTCP(t *testing.T) {
s, _, err := RunLocalTCPServer(":0")
if err != nil {
t.Fatalf("unable to run test server: %v", err)
}
err = s.Shutdown()
if err != nil {
t.Errorf("could not shutdown test TCP server, %v", err)
}
}
func TestShutdownTLS(t *testing.T) {
cert, err := tls.X509KeyPair(CertPEMBlock, KeyPEMBlock)
if err != nil {
t.Fatalf("unable to build certificate: %v", err)
}
config := tls.Config{
Certificates: []tls.Certificate{cert},
}
s, _, err := RunLocalTLSServer(":0", &config)
if err != nil {
t.Fatalf("unable to run test server: %v", err)
}
err = s.Shutdown()
if err != nil {
t.Errorf("could not shutdown test TLS server, %v", err)
}
}
type trigger struct {
done bool
sync.RWMutex
}
func (t *trigger) Set() {
t.Lock()
defer t.Unlock()
t.done = true
}
func (t *trigger) Get() bool {
t.RLock()
defer t.RUnlock()
return t.done
}
func TestHandlerCloseTCP(t *testing.T) {
ln, err := net.Listen("tcp", ":0")
if err != nil {
panic(err)
}
addr := ln.Addr().String()
server := &Server{Addr: addr, Net: "tcp", Listener: ln}
hname := "testhandlerclosetcp."
triggered := &trigger{}
HandleFunc(hname, func(w ResponseWriter, r *Msg) {
triggered.Set()
w.Close()
})
defer HandleRemove(hname)
go func() {
defer server.Shutdown()
c := &Client{Net: "tcp"}
m := new(Msg).SetQuestion(hname, 1)
tries := 0
exchange:
_, _, err := c.Exchange(m, addr)
if err != nil && err != io.EOF {
t.Errorf("exchange failed: %s\n", err)
if tries == 3 {
return
}
time.Sleep(time.Second / 10)
tries++
goto exchange
}
}()
server.ActivateAndServe()
if !triggered.Get() {
t.Fatalf("handler never called")
}
}
func TestShutdownUDP(t *testing.T) {
s, _, fin, err := RunLocalUDPServerWithFinChan(":0")
if err != nil {
t.Fatalf("unable to run test server: %v", err)
}
err = s.Shutdown()
if err != nil {
t.Errorf("could not shutdown test UDP server, %v", err)
}
select {
case <-fin:
case <-time.After(2 * time.Second):
t.Error("Could not shutdown test UDP server. Gave up waiting")
}
}
type ExampleFrameLengthWriter struct {
Writer
}
func (e *ExampleFrameLengthWriter) Write(m []byte) (int, error) {
fmt.Println("writing raw DNS message of length", len(m))
return e.Writer.Write(m)
}
func ExampleDecorateWriter() {
// instrument raw DNS message writing
wf := DecorateWriter(func(w Writer) Writer {
return &ExampleFrameLengthWriter{w}
})
// simple UDP server
pc, err := net.ListenPacket("udp", ":0")
if err != nil {
fmt.Println(err.Error())
return
}
server := &Server{
PacketConn: pc,
DecorateWriter: wf,
ReadTimeout: time.Hour, WriteTimeout: time.Hour,
}
waitLock := sync.Mutex{}
waitLock.Lock()
server.NotifyStartedFunc = waitLock.Unlock
defer server.Shutdown()
go func() {
server.ActivateAndServe()
pc.Close()
}()
waitLock.Lock()
HandleFunc("miek.nl.", HelloServer)
c := new(Client)
m := new(Msg)
m.SetQuestion("miek.nl.", TypeTXT)
_, _, err = c.Exchange(m, pc.LocalAddr().String())
if err != nil {
fmt.Println("failed to exchange", err.Error())
return
}
// Output: writing raw DNS message of length 56
}
var (
// CertPEMBlock is a X509 data used to test TLS servers (used with tls.X509KeyPair)
CertPEMBlock = []byte(`-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----`)
// KeyPEMBlock is a X509 data used to test TLS servers (used with tls.X509KeyPair)
KeyPEMBlock = []byte(`-----BEGIN RSA PRIVATE KEY-----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-----END RSA PRIVATE KEY-----`)
)