diff options
Diffstat (limited to 'vendor/github.com/Microsoft/go-winio/pipe.go')
-rw-r--r-- | vendor/github.com/Microsoft/go-winio/pipe.go | 404 |
1 files changed, 404 insertions, 0 deletions
diff --git a/vendor/github.com/Microsoft/go-winio/pipe.go b/vendor/github.com/Microsoft/go-winio/pipe.go new file mode 100644 index 000000000..44340b816 --- /dev/null +++ b/vendor/github.com/Microsoft/go-winio/pipe.go @@ -0,0 +1,404 @@ +// +build windows + +package winio + +import ( + "errors" + "io" + "net" + "os" + "syscall" + "time" + "unsafe" +) + +//sys connectNamedPipe(pipe syscall.Handle, o *syscall.Overlapped) (err error) = ConnectNamedPipe +//sys createNamedPipe(name string, flags uint32, pipeMode uint32, maxInstances uint32, outSize uint32, inSize uint32, defaultTimeout uint32, sa *syscall.SecurityAttributes) (handle syscall.Handle, err error) [failretval==syscall.InvalidHandle] = CreateNamedPipeW +//sys createFile(name string, access uint32, mode uint32, sa *syscall.SecurityAttributes, createmode uint32, attrs uint32, templatefile syscall.Handle) (handle syscall.Handle, err error) [failretval==syscall.InvalidHandle] = CreateFileW +//sys waitNamedPipe(name string, timeout uint32) (err error) = WaitNamedPipeW +//sys getNamedPipeInfo(pipe syscall.Handle, flags *uint32, outSize *uint32, inSize *uint32, maxInstances *uint32) (err error) = GetNamedPipeInfo +//sys getNamedPipeHandleState(pipe syscall.Handle, state *uint32, curInstances *uint32, maxCollectionCount *uint32, collectDataTimeout *uint32, userName *uint16, maxUserNameSize uint32) (err error) = GetNamedPipeHandleStateW +//sys localAlloc(uFlags uint32, length uint32) (ptr uintptr) = LocalAlloc + +const ( + cERROR_PIPE_BUSY = syscall.Errno(231) + cERROR_PIPE_CONNECTED = syscall.Errno(535) + cERROR_SEM_TIMEOUT = syscall.Errno(121) + + cPIPE_ACCESS_DUPLEX = 0x3 + cFILE_FLAG_FIRST_PIPE_INSTANCE = 0x80000 + cSECURITY_SQOS_PRESENT = 0x100000 + cSECURITY_ANONYMOUS = 0 + + cPIPE_REJECT_REMOTE_CLIENTS = 0x8 + + cPIPE_UNLIMITED_INSTANCES = 255 + + cNMPWAIT_USE_DEFAULT_WAIT = 0 + cNMPWAIT_NOWAIT = 1 + + cPIPE_TYPE_MESSAGE = 4 + + cPIPE_READMODE_MESSAGE = 2 +) + +var ( + // ErrPipeListenerClosed is returned for pipe operations on listeners that have been closed. + // This error should match net.errClosing since docker takes a dependency on its text. + ErrPipeListenerClosed = errors.New("use of closed network connection") + + errPipeWriteClosed = errors.New("pipe has been closed for write") +) + +type win32Pipe struct { + *win32File + path string +} + +type win32MessageBytePipe struct { + win32Pipe + writeClosed bool + readEOF bool +} + +type pipeAddress string + +func (f *win32Pipe) LocalAddr() net.Addr { + return pipeAddress(f.path) +} + +func (f *win32Pipe) RemoteAddr() net.Addr { + return pipeAddress(f.path) +} + +func (f *win32Pipe) SetDeadline(t time.Time) error { + f.SetReadDeadline(t) + f.SetWriteDeadline(t) + return nil +} + +// CloseWrite closes the write side of a message pipe in byte mode. +func (f *win32MessageBytePipe) CloseWrite() error { + if f.writeClosed { + return errPipeWriteClosed + } + err := f.win32File.Flush() + if err != nil { + return err + } + _, err = f.win32File.Write(nil) + if err != nil { + return err + } + f.writeClosed = true + return nil +} + +// Write writes bytes to a message pipe in byte mode. Zero-byte writes are ignored, since +// they are used to implement CloseWrite(). +func (f *win32MessageBytePipe) Write(b []byte) (int, error) { + if f.writeClosed { + return 0, errPipeWriteClosed + } + if len(b) == 0 { + return 0, nil + } + return f.win32File.Write(b) +} + +// Read reads bytes from a message pipe in byte mode. A read of a zero-byte message on a message +// mode pipe will return io.EOF, as will all subsequent reads. +func (f *win32MessageBytePipe) Read(b []byte) (int, error) { + if f.readEOF { + return 0, io.EOF + } + n, err := f.win32File.Read(b) + if err == io.EOF { + // If this was the result of a zero-byte read, then + // it is possible that the read was due to a zero-size + // message. Since we are simulating CloseWrite with a + // zero-byte message, ensure that all future Read() calls + // also return EOF. + f.readEOF = true + } + return n, err +} + +func (s pipeAddress) Network() string { + return "pipe" +} + +func (s pipeAddress) String() string { + return string(s) +} + +// DialPipe connects to a named pipe by path, timing out if the connection +// takes longer than the specified duration. If timeout is nil, then the timeout +// is the default timeout established by the pipe server. +func DialPipe(path string, timeout *time.Duration) (net.Conn, error) { + var absTimeout time.Time + if timeout != nil { + absTimeout = time.Now().Add(*timeout) + } + var err error + var h syscall.Handle + for { + h, err = createFile(path, syscall.GENERIC_READ|syscall.GENERIC_WRITE, 0, nil, syscall.OPEN_EXISTING, syscall.FILE_FLAG_OVERLAPPED|cSECURITY_SQOS_PRESENT|cSECURITY_ANONYMOUS, 0) + if err != cERROR_PIPE_BUSY { + break + } + now := time.Now() + var ms uint32 + if absTimeout.IsZero() { + ms = cNMPWAIT_USE_DEFAULT_WAIT + } else if now.After(absTimeout) { + ms = cNMPWAIT_NOWAIT + } else { + ms = uint32(absTimeout.Sub(now).Nanoseconds() / 1000 / 1000) + } + err = waitNamedPipe(path, ms) + if err != nil { + if err == cERROR_SEM_TIMEOUT { + return nil, ErrTimeout + } + break + } + } + if err != nil { + return nil, &os.PathError{Op: "open", Path: path, Err: err} + } + + var flags uint32 + err = getNamedPipeInfo(h, &flags, nil, nil, nil) + if err != nil { + return nil, err + } + + var state uint32 + err = getNamedPipeHandleState(h, &state, nil, nil, nil, nil, 0) + if err != nil { + return nil, err + } + + if state&cPIPE_READMODE_MESSAGE != 0 { + return nil, &os.PathError{Op: "open", Path: path, Err: errors.New("message readmode pipes not supported")} + } + + f, err := makeWin32File(h) + if err != nil { + syscall.Close(h) + return nil, err + } + + // If the pipe is in message mode, return a message byte pipe, which + // supports CloseWrite(). + if flags&cPIPE_TYPE_MESSAGE != 0 { + return &win32MessageBytePipe{ + win32Pipe: win32Pipe{win32File: f, path: path}, + }, nil + } + return &win32Pipe{win32File: f, path: path}, nil +} + +type acceptResponse struct { + f *win32File + err error +} + +type win32PipeListener struct { + firstHandle syscall.Handle + path string + securityDescriptor []byte + config PipeConfig + acceptCh chan (chan acceptResponse) + closeCh chan int + doneCh chan int +} + +func makeServerPipeHandle(path string, securityDescriptor []byte, c *PipeConfig, first bool) (syscall.Handle, error) { + var flags uint32 = cPIPE_ACCESS_DUPLEX | syscall.FILE_FLAG_OVERLAPPED + if first { + flags |= cFILE_FLAG_FIRST_PIPE_INSTANCE + } + + var mode uint32 = cPIPE_REJECT_REMOTE_CLIENTS + if c.MessageMode { + mode |= cPIPE_TYPE_MESSAGE + } + + sa := &syscall.SecurityAttributes{} + sa.Length = uint32(unsafe.Sizeof(*sa)) + if securityDescriptor != nil { + len := uint32(len(securityDescriptor)) + sa.SecurityDescriptor = localAlloc(0, len) + defer localFree(sa.SecurityDescriptor) + copy((*[0xffff]byte)(unsafe.Pointer(sa.SecurityDescriptor))[:], securityDescriptor) + } + h, err := createNamedPipe(path, flags, mode, cPIPE_UNLIMITED_INSTANCES, uint32(c.OutputBufferSize), uint32(c.InputBufferSize), 0, sa) + if err != nil { + return 0, &os.PathError{Op: "open", Path: path, Err: err} + } + return h, nil +} + +func (l *win32PipeListener) makeServerPipe() (*win32File, error) { + h, err := makeServerPipeHandle(l.path, l.securityDescriptor, &l.config, false) + if err != nil { + return nil, err + } + f, err := makeWin32File(h) + if err != nil { + syscall.Close(h) + return nil, err + } + return f, nil +} + +func (l *win32PipeListener) listenerRoutine() { + closed := false + for !closed { + select { + case <-l.closeCh: + closed = true + case responseCh := <-l.acceptCh: + p, err := l.makeServerPipe() + if err == nil { + // Wait for the client to connect. + ch := make(chan error) + go func(p *win32File) { + ch <- connectPipe(p) + }(p) + select { + case err = <-ch: + if err != nil { + p.Close() + p = nil + } + case <-l.closeCh: + // Abort the connect request by closing the handle. + p.Close() + p = nil + err = <-ch + if err == nil || err == ErrFileClosed { + err = ErrPipeListenerClosed + } + closed = true + } + } + responseCh <- acceptResponse{p, err} + } + } + syscall.Close(l.firstHandle) + l.firstHandle = 0 + // Notify Close() and Accept() callers that the handle has been closed. + close(l.doneCh) +} + +// PipeConfig contain configuration for the pipe listener. +type PipeConfig struct { + // SecurityDescriptor contains a Windows security descriptor in SDDL format. + SecurityDescriptor string + + // MessageMode determines whether the pipe is in byte or message mode. In either + // case the pipe is read in byte mode by default. The only practical difference in + // this implementation is that CloseWrite() is only supported for message mode pipes; + // CloseWrite() is implemented as a zero-byte write, but zero-byte writes are only + // transferred to the reader (and returned as io.EOF in this implementation) + // when the pipe is in message mode. + MessageMode bool + + // InputBufferSize specifies the size the input buffer, in bytes. + InputBufferSize int32 + + // OutputBufferSize specifies the size the input buffer, in bytes. + OutputBufferSize int32 +} + +// ListenPipe creates a listener on a Windows named pipe path, e.g. \\.\pipe\mypipe. +// The pipe must not already exist. +func ListenPipe(path string, c *PipeConfig) (net.Listener, error) { + var ( + sd []byte + err error + ) + if c == nil { + c = &PipeConfig{} + } + if c.SecurityDescriptor != "" { + sd, err = SddlToSecurityDescriptor(c.SecurityDescriptor) + if err != nil { + return nil, err + } + } + h, err := makeServerPipeHandle(path, sd, c, true) + if err != nil { + return nil, err + } + // Immediately open and then close a client handle so that the named pipe is + // created but not currently accepting connections. + h2, err := createFile(path, 0, 0, nil, syscall.OPEN_EXISTING, cSECURITY_SQOS_PRESENT|cSECURITY_ANONYMOUS, 0) + if err != nil { + syscall.Close(h) + return nil, err + } + syscall.Close(h2) + l := &win32PipeListener{ + firstHandle: h, + path: path, + securityDescriptor: sd, + config: *c, + acceptCh: make(chan (chan acceptResponse)), + closeCh: make(chan int), + doneCh: make(chan int), + } + go l.listenerRoutine() + return l, nil +} + +func connectPipe(p *win32File) error { + c, err := p.prepareIo() + if err != nil { + return err + } + defer p.wg.Done() + + err = connectNamedPipe(p.handle, &c.o) + _, err = p.asyncIo(c, nil, 0, err) + if err != nil && err != cERROR_PIPE_CONNECTED { + return err + } + return nil +} + +func (l *win32PipeListener) Accept() (net.Conn, error) { + ch := make(chan acceptResponse) + select { + case l.acceptCh <- ch: + response := <-ch + err := response.err + if err != nil { + return nil, err + } + if l.config.MessageMode { + return &win32MessageBytePipe{ + win32Pipe: win32Pipe{win32File: response.f, path: l.path}, + }, nil + } + return &win32Pipe{win32File: response.f, path: l.path}, nil + case <-l.doneCh: + return nil, ErrPipeListenerClosed + } +} + +func (l *win32PipeListener) Close() error { + select { + case l.closeCh <- 1: + <-l.doneCh + case <-l.doneCh: + } + return nil +} + +func (l *win32PipeListener) Addr() net.Addr { + return pipeAddress(l.path) +} |