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winpipe: move syscalls into x/sys
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Signed-off-by: Jason A. Donenfeld <[email protected]>
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@zx2c4
zx2c4 committed Mar 6, 2021
1 parent c1b1fd4 commit 7e3b837
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Showing 7 changed files with 1,174 additions and 837 deletions.
4 changes: 2 additions & 2 deletions ipc/uapi_windows.go
View file
Original file line number Diff line number Diff line change
Expand Up @@ -62,10 +62,10 @@ func init() {
}

func UAPIListen(name string) (net.Listener, error) {
config := winpipe.PipeConfig{
config := winpipe.ListenConfig{
SecurityDescriptor: UAPISecurityDescriptor,
}
listener, err := winpipe.ListenPipe(`\\.\pipe\ProtectedPrefix\Administrators\WireGuard\`+name, &config)
listener, err := winpipe.Listen(`\\.\pipe\ProtectedPrefix\Administrators\WireGuard\`+name, &config)
if err != nil {
return nil, err
}
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121 changes: 42 additions & 79 deletions ipc/winpipe/file.go
View file
Original file line number Diff line number Diff line change
Expand Up @@ -5,54 +5,21 @@
* Copyright (C) 2005 Microsoft
* Copyright (C) 2017-2021 WireGuard LLC. All Rights Reserved.
*/

package winpipe

import (
"errors"
"io"
"os"
"runtime"
"sync"
"sync/atomic"
"time"
"unsafe"

"golang.org/x/sys/windows"
)

//sys cancelIoEx(file windows.Handle, o *windows.Overlapped) (err error) = CancelIoEx
//sys createIoCompletionPort(file windows.Handle, port windows.Handle, key uintptr, threadCount uint32) (newport windows.Handle, err error) = CreateIoCompletionPort
//sys getQueuedCompletionStatus(port windows.Handle, bytes *uint32, key *uintptr, o **ioOperation, timeout uint32) (err error) = GetQueuedCompletionStatus
//sys setFileCompletionNotificationModes(h windows.Handle, flags uint8) (err error) = SetFileCompletionNotificationModes
//sys wsaGetOverlappedResult(h windows.Handle, o *windows.Overlapped, bytes *uint32, wait bool, flags *uint32) (err error) = ws2_32.WSAGetOverlappedResult

type atomicBool int32

func (b *atomicBool) isSet() bool { return atomic.LoadInt32((*int32)(b)) != 0 }
func (b *atomicBool) setFalse() { atomic.StoreInt32((*int32)(b), 0) }
func (b *atomicBool) setTrue() { atomic.StoreInt32((*int32)(b), 1) }
func (b *atomicBool) swap(new bool) bool {
var newInt int32
if new {
newInt = 1
}
return atomic.SwapInt32((*int32)(b), newInt) == 1
}

const (
cFILE_SKIP_COMPLETION_PORT_ON_SUCCESS = 1
cFILE_SKIP_SET_EVENT_ON_HANDLE = 2
)

var (
ErrFileClosed = errors.New("file has already been closed")
ErrTimeout = &timeoutError{}
)

type timeoutError struct{}

func (e *timeoutError) Error() string { return "i/o timeout" }
func (e *timeoutError) Timeout() bool { return true }
func (e *timeoutError) Temporary() bool { return true }

type timeoutChan chan struct{}

var ioInitOnce sync.Once
Expand All @@ -71,21 +38,21 @@ type ioOperation struct {
}

func initIo() {
h, err := createIoCompletionPort(windows.InvalidHandle, 0, 0, 0xffffffff)
h, err := windows.CreateIoCompletionPort(windows.InvalidHandle, 0, 0, 0)
if err != nil {
panic(err)
}
ioCompletionPort = h
go ioCompletionProcessor(h)
}

// win32File implements Reader, Writer, and Closer on a Win32 handle without blocking in a syscall.
// file implements Reader, Writer, and Closer on a Win32 handle without blocking in a syscall.
// It takes ownership of this handle and will close it if it is garbage collected.
type win32File struct {
type file struct {
handle windows.Handle
wg sync.WaitGroup
wgLock sync.RWMutex
closing atomicBool
closing uint32 // used as atomic boolean
socket bool
readDeadline deadlineHandler
writeDeadline deadlineHandler
Expand All @@ -96,18 +63,18 @@ type deadlineHandler struct {
channel timeoutChan
channelLock sync.RWMutex
timer *time.Timer
timedout atomicBool
timedout uint32 // used as atomic boolean
}

// makeWin32File makes a new win32File from an existing file handle
func makeWin32File(h windows.Handle) (*win32File, error) {
f := &win32File{handle: h}
// makeFile makes a new file from an existing file handle
func makeFile(h windows.Handle) (*file, error) {
f := &file{handle: h}
ioInitOnce.Do(initIo)
_, err := createIoCompletionPort(h, ioCompletionPort, 0, 0xffffffff)
_, err := windows.CreateIoCompletionPort(h, ioCompletionPort, 0, 0)
if err != nil {
return nil, err
}
err = setFileCompletionNotificationModes(h, cFILE_SKIP_COMPLETION_PORT_ON_SUCCESS|cFILE_SKIP_SET_EVENT_ON_HANDLE)
err = windows.SetFileCompletionNotificationModes(h, windows.FILE_SKIP_COMPLETION_PORT_ON_SUCCESS|windows.FILE_SKIP_SET_EVENT_ON_HANDLE)
if err != nil {
return nil, err
}
Expand All @@ -116,18 +83,14 @@ func makeWin32File(h windows.Handle) (*win32File, error) {
return f, nil
}

func MakeOpenFile(h windows.Handle) (io.ReadWriteCloser, error) {
return makeWin32File(h)
}

// closeHandle closes the resources associated with a Win32 handle
func (f *win32File) closeHandle() {
func (f *file) closeHandle() {
f.wgLock.Lock()
// Atomically set that we are closing, releasing the resources only once.
if !f.closing.swap(true) {
if atomic.SwapUint32(&f.closing, 1) == 0 {
f.wgLock.Unlock()
// cancel all IO and wait for it to complete
cancelIoEx(f.handle, nil)
windows.CancelIoEx(f.handle, nil)
f.wg.Wait()
// at this point, no new IO can start
windows.Close(f.handle)
Expand All @@ -137,19 +100,19 @@ func (f *win32File) closeHandle() {
}
}

// Close closes a win32File.
func (f *win32File) Close() error {
// Close closes a file.
func (f *file) Close() error {
f.closeHandle()
return nil
}

// prepareIo prepares for a new IO operation.
// The caller must call f.wg.Done() when the IO is finished, prior to Close() returning.
func (f *win32File) prepareIo() (*ioOperation, error) {
func (f *file) prepareIo() (*ioOperation, error) {
f.wgLock.RLock()
if f.closing.isSet() {
if atomic.LoadUint32(&f.closing) == 1 {
f.wgLock.RUnlock()
return nil, ErrFileClosed
return nil, os.ErrClosed
}
f.wg.Add(1)
f.wgLock.RUnlock()
Expand All @@ -164,7 +127,7 @@ func ioCompletionProcessor(h windows.Handle) {
var bytes uint32
var key uintptr
var op *ioOperation
err := getQueuedCompletionStatus(h, &bytes, &key, &op, windows.INFINITE)
err := windows.GetQueuedCompletionStatus(h, &bytes, &key, (**windows.Overlapped)(unsafe.Pointer(&op)), windows.INFINITE)
if op == nil {
panic(err)
}
Expand All @@ -174,13 +137,13 @@ func ioCompletionProcessor(h windows.Handle) {

// asyncIo processes the return value from ReadFile or WriteFile, blocking until
// the operation has actually completed.
func (f *win32File) asyncIo(c *ioOperation, d *deadlineHandler, bytes uint32, err error) (int, error) {
func (f *file) asyncIo(c *ioOperation, d *deadlineHandler, bytes uint32, err error) (int, error) {
if err != windows.ERROR_IO_PENDING {
return int(bytes), err
}

if f.closing.isSet() {
cancelIoEx(f.handle, &c.o)
if atomic.LoadUint32(&f.closing) == 1 {
windows.CancelIoEx(f.handle, &c.o)
}

var timeout timeoutChan
Expand All @@ -195,20 +158,20 @@ func (f *win32File) asyncIo(c *ioOperation, d *deadlineHandler, bytes uint32, er
case r = <-c.ch:
err = r.err
if err == windows.ERROR_OPERATION_ABORTED {
if f.closing.isSet() {
err = ErrFileClosed
if atomic.LoadUint32(&f.closing) == 1 {
err = os.ErrClosed
}
} else if err != nil && f.socket {
// err is from Win32. Query the overlapped structure to get the winsock error.
var bytes, flags uint32
err = wsaGetOverlappedResult(f.handle, &c.o, &bytes, false, &flags)
err = windows.WSAGetOverlappedResult(f.handle, &c.o, &bytes, false, &flags)
}
case <-timeout:
cancelIoEx(f.handle, &c.o)
windows.CancelIoEx(f.handle, &c.o)
r = <-c.ch
err = r.err
if err == windows.ERROR_OPERATION_ABORTED {
err = ErrTimeout
err = os.ErrDeadlineExceeded
}
}

Expand All @@ -220,15 +183,15 @@ func (f *win32File) asyncIo(c *ioOperation, d *deadlineHandler, bytes uint32, er
}

// Read reads from a file handle.
func (f *win32File) Read(b []byte) (int, error) {
func (f *file) Read(b []byte) (int, error) {
c, err := f.prepareIo()
if err != nil {
return 0, err
}
defer f.wg.Done()

if f.readDeadline.timedout.isSet() {
return 0, ErrTimeout
if atomic.LoadUint32(&f.readDeadline.timedout) == 1 {
return 0, os.ErrDeadlineExceeded
}

var bytes uint32
Expand All @@ -247,15 +210,15 @@ func (f *win32File) Read(b []byte) (int, error) {
}

// Write writes to a file handle.
func (f *win32File) Write(b []byte) (int, error) {
func (f *file) Write(b []byte) (int, error) {
c, err := f.prepareIo()
if err != nil {
return 0, err
}
defer f.wg.Done()

if f.writeDeadline.timedout.isSet() {
return 0, ErrTimeout
if atomic.LoadUint32(&f.writeDeadline.timedout) == 1 {
return 0, os.ErrDeadlineExceeded
}

var bytes uint32
Expand All @@ -265,19 +228,19 @@ func (f *win32File) Write(b []byte) (int, error) {
return n, err
}

func (f *win32File) SetReadDeadline(deadline time.Time) error {
func (f *file) SetReadDeadline(deadline time.Time) error {
return f.readDeadline.set(deadline)
}

func (f *win32File) SetWriteDeadline(deadline time.Time) error {
func (f *file) SetWriteDeadline(deadline time.Time) error {
return f.writeDeadline.set(deadline)
}

func (f *win32File) Flush() error {
func (f *file) Flush() error {
return windows.FlushFileBuffers(f.handle)
}

func (f *win32File) Fd() uintptr {
func (f *file) Fd() uintptr {
return uintptr(f.handle)
}

Expand All @@ -291,7 +254,7 @@ func (d *deadlineHandler) set(deadline time.Time) error {
}
d.timer = nil
}
d.timedout.setFalse()
atomic.StoreUint32(&d.timedout, 0)

select {
case <-d.channel:
Expand All @@ -306,7 +269,7 @@ func (d *deadlineHandler) set(deadline time.Time) error {
}

timeoutIO := func() {
d.timedout.setTrue()
atomic.StoreUint32(&d.timedout, 1)
close(d.channel)
}

Expand Down
9 changes: 0 additions & 9 deletions ipc/winpipe/mksyscall.go
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