Files
go-winio/pipe_test.go
T
John Starks bd71ef0e5d pipe: Fix ListenPipe/DialPipe race
ListenPipe can fail if there is a concurrent DialPipe because there is a
race window where DialPipe can connect to the initial server named pipe
before it is connected to and closed by ListenPipe.

To fix this, use the lower-level NT API for creating the server pipe,
since this API allows for specifying that a server pipe should initially
be in the disconnected state instead of the listening state. This allows
us to avoid the race condition by creating the pipe in the correct state
initially, so there is no longer a need to create a dummy client
connection.
2019-04-08 10:08:23 -07:00

538 lines
9.6 KiB
Go

package winio
import (
"bufio"
"bytes"
"io"
"net"
"os"
"sync"
"syscall"
"testing"
"time"
"unsafe"
)
var testPipeName = `\\.\pipe\winiotestpipe`
var aLongTimeAgo = time.Unix(1, 0)
func TestDialUnknownFailsImmediately(t *testing.T) {
_, err := DialPipe(testPipeName, nil)
if err.(*os.PathError).Err != syscall.ENOENT {
t.Fatalf("expected ENOENT got %v", err)
}
}
func TestDialListenerTimesOut(t *testing.T) {
l, err := ListenPipe(testPipeName, nil)
if err != nil {
t.Fatal(err)
}
defer l.Close()
var d = time.Duration(10 * time.Millisecond)
_, err = DialPipe(testPipeName, &d)
if err != ErrTimeout {
t.Fatalf("expected ErrTimeout, got %v", err)
}
}
func TestDialAccessDeniedWithRestrictedSD(t *testing.T) {
c := PipeConfig{
SecurityDescriptor: "D:P(A;;0x1200FF;;;WD)",
}
l, err := ListenPipe(testPipeName, &c)
if err != nil {
t.Fatal(err)
}
defer l.Close()
_, err = DialPipe(testPipeName, nil)
if err.(*os.PathError).Err != syscall.ERROR_ACCESS_DENIED {
t.Fatalf("expected ERROR_ACCESS_DENIED, got %v", err)
}
}
func getConnection(cfg *PipeConfig) (client net.Conn, server net.Conn, err error) {
l, err := ListenPipe(testPipeName, cfg)
if err != nil {
return
}
defer l.Close()
type response struct {
c net.Conn
err error
}
ch := make(chan response)
go func() {
c, err := l.Accept()
ch <- response{c, err}
}()
c, err := DialPipe(testPipeName, nil)
if err != nil {
return
}
r := <-ch
if err = r.err; err != nil {
c.Close()
return
}
client = c
server = r.c
return
}
func TestReadTimeout(t *testing.T) {
c, s, err := getConnection(nil)
if err != nil {
t.Fatal(err)
}
defer c.Close()
defer s.Close()
c.SetReadDeadline(time.Now().Add(10 * time.Millisecond))
buf := make([]byte, 10)
_, err = c.Read(buf)
if err != ErrTimeout {
t.Fatalf("expected ErrTimeout, got %v", err)
}
}
func server(l net.Listener, ch chan int) {
c, err := l.Accept()
if err != nil {
panic(err)
}
rw := bufio.NewReadWriter(bufio.NewReader(c), bufio.NewWriter(c))
s, err := rw.ReadString('\n')
if err != nil {
panic(err)
}
_, err = rw.WriteString("got " + s)
if err != nil {
panic(err)
}
err = rw.Flush()
if err != nil {
panic(err)
}
c.Close()
ch <- 1
}
func TestFullListenDialReadWrite(t *testing.T) {
l, err := ListenPipe(testPipeName, nil)
if err != nil {
t.Fatal(err)
}
defer l.Close()
ch := make(chan int)
go server(l, ch)
c, err := DialPipe(testPipeName, nil)
if err != nil {
t.Fatal(err)
}
defer c.Close()
rw := bufio.NewReadWriter(bufio.NewReader(c), bufio.NewWriter(c))
_, err = rw.WriteString("hello world\n")
if err != nil {
t.Fatal(err)
}
err = rw.Flush()
if err != nil {
t.Fatal(err)
}
s, err := rw.ReadString('\n')
if err != nil {
t.Fatal(err)
}
ms := "got hello world\n"
if s != ms {
t.Errorf("expected '%s', got '%s'", ms, s)
}
<-ch
}
func TestCloseAbortsListen(t *testing.T) {
l, err := ListenPipe(testPipeName, nil)
if err != nil {
t.Fatal(err)
}
ch := make(chan error)
go func() {
_, err := l.Accept()
ch <- err
}()
time.Sleep(30 * time.Millisecond)
l.Close()
err = <-ch
if err != ErrPipeListenerClosed {
t.Fatalf("expected ErrPipeListenerClosed, got %v", err)
}
}
func ensureEOFOnClose(t *testing.T, r io.Reader, w io.Closer) {
b := make([]byte, 10)
w.Close()
n, err := r.Read(b)
if n > 0 {
t.Errorf("unexpected byte count %d", n)
}
if err != io.EOF {
t.Errorf("expected EOF: %v", err)
}
}
func TestCloseClientEOFServer(t *testing.T) {
c, s, err := getConnection(nil)
if err != nil {
t.Fatal(err)
}
defer c.Close()
defer s.Close()
ensureEOFOnClose(t, c, s)
}
func TestCloseServerEOFClient(t *testing.T) {
c, s, err := getConnection(nil)
if err != nil {
t.Fatal(err)
}
defer c.Close()
defer s.Close()
ensureEOFOnClose(t, s, c)
}
func TestCloseWriteEOF(t *testing.T) {
cfg := &PipeConfig{
MessageMode: true,
}
c, s, err := getConnection(cfg)
if err != nil {
t.Fatal(err)
}
defer c.Close()
defer s.Close()
type closeWriter interface {
CloseWrite() error
}
err = c.(closeWriter).CloseWrite()
if err != nil {
t.Fatal(err)
}
b := make([]byte, 10)
_, err = s.Read(b)
if err != io.EOF {
t.Fatal(err)
}
}
func TestAcceptAfterCloseFails(t *testing.T) {
l, err := ListenPipe(testPipeName, nil)
if err != nil {
t.Fatal(err)
}
l.Close()
_, err = l.Accept()
if err != ErrPipeListenerClosed {
t.Fatalf("expected ErrPipeListenerClosed, got %v", err)
}
}
func TestDialTimesOutByDefault(t *testing.T) {
l, err := ListenPipe(testPipeName, nil)
if err != nil {
t.Fatal(err)
}
defer l.Close()
_, err = DialPipe(testPipeName, nil)
if err != ErrTimeout {
t.Fatalf("expected ErrTimeout, got %v", err)
}
}
func TestTimeoutPendingRead(t *testing.T) {
l, err := ListenPipe(testPipeName, nil)
if err != nil {
t.Fatal(err)
}
defer l.Close()
serverDone := make(chan struct{})
go func() {
s, err := l.Accept()
if err != nil {
t.Fatal(err)
}
time.Sleep(1 * time.Second)
s.Close()
close(serverDone)
}()
client, err := DialPipe(testPipeName, nil)
if err != nil {
t.Fatal(err)
}
defer client.Close()
clientErr := make(chan error)
go func() {
buf := make([]byte, 10)
_, err = client.Read(buf)
clientErr <- err
}()
time.Sleep(100 * time.Millisecond) // make *sure* the pipe is reading before we set the deadline
client.SetReadDeadline(aLongTimeAgo)
select {
case err = <-clientErr:
if err != ErrTimeout {
t.Fatalf("expected ErrTimeout, got %v", err)
}
case <-time.After(100 * time.Millisecond):
t.Fatalf("timed out while waiting for read to cancel")
<-clientErr
}
<-serverDone
}
func TestTimeoutPendingWrite(t *testing.T) {
l, err := ListenPipe(testPipeName, nil)
if err != nil {
t.Fatal(err)
}
defer l.Close()
serverDone := make(chan struct{})
go func() {
s, err := l.Accept()
if err != nil {
t.Fatal(err)
}
time.Sleep(1 * time.Second)
s.Close()
close(serverDone)
}()
client, err := DialPipe(testPipeName, nil)
if err != nil {
t.Fatal(err)
}
defer client.Close()
clientErr := make(chan error)
go func() {
_, err = client.Write([]byte("this should timeout"))
clientErr <- err
}()
time.Sleep(100 * time.Millisecond) // make *sure* the pipe is writing before we set the deadline
client.SetWriteDeadline(aLongTimeAgo)
select {
case err = <-clientErr:
if err != ErrTimeout {
t.Fatalf("expected ErrTimeout, got %v", err)
}
case <-time.After(100 * time.Millisecond):
t.Fatalf("timed out while waiting for write to cancel")
<-clientErr
}
<-serverDone
}
type CloseWriter interface {
CloseWrite() error
}
func TestEchoWithMessaging(t *testing.T) {
c := PipeConfig{
MessageMode: true, // Use message mode so that CloseWrite() is supported
InputBufferSize: 65536, // Use 64KB buffers to improve performance
OutputBufferSize: 65536,
}
l, err := ListenPipe(testPipeName, &c)
if err != nil {
t.Fatal(err)
}
defer l.Close()
listenerDone := make(chan bool)
clientDone := make(chan bool)
go func() {
// server echo
conn, e := l.Accept()
if e != nil {
t.Fatal(e)
}
defer conn.Close()
time.Sleep(500 * time.Millisecond) // make *sure* we don't begin to read before eof signal is sent
io.Copy(conn, conn)
conn.(CloseWriter).CloseWrite()
close(listenerDone)
}()
timeout := 1 * time.Second
client, err := DialPipe(testPipeName, &timeout)
if err != nil {
t.Fatal(err)
}
defer client.Close()
go func() {
// client read back
bytes := make([]byte, 2)
n, e := client.Read(bytes)
if e != nil {
t.Fatal(e)
}
if n != 2 {
t.Fatalf("expected 2 bytes, got %v", n)
}
close(clientDone)
}()
payload := make([]byte, 2)
payload[0] = 0
payload[1] = 1
n, err := client.Write(payload)
if err != nil {
t.Fatal(err)
}
if n != 2 {
t.Fatalf("expected 2 bytes, got %v", n)
}
client.(CloseWriter).CloseWrite()
<-listenerDone
<-clientDone
}
func TestConnectRace(t *testing.T) {
l, err := ListenPipe(testPipeName, nil)
if err != nil {
t.Fatal(err)
}
defer l.Close()
go func() {
for {
s, err := l.Accept()
if err == ErrPipeListenerClosed {
return
}
if err != nil {
t.Fatal(err)
}
s.Close()
}
}()
for i := 0; i < 1000; i++ {
c, err := DialPipe(testPipeName, nil)
if err != nil {
t.Fatal(err)
}
c.Close()
}
}
func TestMessageReadMode(t *testing.T) {
var wg sync.WaitGroup
defer wg.Wait()
l, err := ListenPipe(testPipeName, &PipeConfig{MessageMode: true})
if err != nil {
t.Fatal(err)
}
defer l.Close()
msg := ([]byte)("hello world")
wg.Add(1)
go func() {
defer wg.Done()
s, err := l.Accept()
if err != nil {
t.Fatal(err)
}
_, err = s.Write(msg)
if err != nil {
t.Fatal(err)
}
s.Close()
}()
c, err := DialPipe(testPipeName, nil)
if err != nil {
t.Fatal(err)
}
defer c.Close()
setNamedPipeHandleState := syscall.NewLazyDLL("kernel32.dll").NewProc("SetNamedPipeHandleState")
p := c.(*win32MessageBytePipe)
mode := uint32(cPIPE_READMODE_MESSAGE)
if s, _, err := setNamedPipeHandleState.Call(uintptr(p.handle), uintptr(unsafe.Pointer(&mode)), 0, 0); s == 0 {
t.Fatal(err)
}
ch := make([]byte, 1)
var vmsg []byte
for {
n, err := c.Read(ch)
if err == io.EOF {
break
}
if err != nil {
t.Fatal(err)
}
if n != 1 {
t.Fatal("expected 1: ", n)
}
vmsg = append(vmsg, ch[0])
}
if !bytes.Equal(msg, vmsg) {
t.Fatalf("expected %s: %s", msg, vmsg)
}
}
func TestListenConnectRace(t *testing.T) {
for i := 0; i < 50 && !t.Failed(); i++ {
var wg sync.WaitGroup
wg.Add(1)
go func() {
c, err := DialPipe(testPipeName, nil)
if err == nil {
c.Close()
}
wg.Done()
}()
s, err := ListenPipe(testPipeName, nil)
if err != nil {
t.Error(i, err)
} else {
s.Close()
}
wg.Wait()
}
}