diff options
author | Jason A. Donenfeld <Jason@zx2c4.com> | 2019-05-23 14:53:44 +0200 |
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committer | Jason A. Donenfeld <Jason@zx2c4.com> | 2019-05-23 15:16:02 +0200 |
commit | a74a29bc937cf75c1af4166e746df49ef53b2fc2 (patch) | |
tree | 1d9c3ad1ca48fa370fd25b3a86007ec70466be4e /ipc/winpipe/pipe.go | |
parent | dc9bbec9dbca1daff8265b6e6da6b36185e74660 (diff) |
ipc: use simplified fork of winio
Diffstat (limited to 'ipc/winpipe/pipe.go')
-rw-r--r-- | ipc/winpipe/pipe.go | 516 |
1 files changed, 516 insertions, 0 deletions
diff --git a/ipc/winpipe/pipe.go b/ipc/winpipe/pipe.go new file mode 100644 index 0000000..1e99a93 --- /dev/null +++ b/ipc/winpipe/pipe.go @@ -0,0 +1,516 @@ +// +build windows + +/* SPDX-License-Identifier: MIT + * + * Copyright (C) 2005 Microsoft + * Copyright (C) 2017-2019 WireGuard LLC. All Rights Reserved. + */ + +package winpipe + +import ( + "context" + "errors" + "fmt" + "io" + "net" + "os" + "runtime" + "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 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 +//sys ntCreateNamedPipeFile(pipe *syscall.Handle, access uint32, oa *objectAttributes, iosb *ioStatusBlock, share uint32, disposition uint32, options uint32, typ uint32, readMode uint32, completionMode uint32, maxInstances uint32, inboundQuota uint32, outputQuota uint32, timeout *int64) (status ntstatus) = ntdll.NtCreateNamedPipeFile +//sys rtlNtStatusToDosError(status ntstatus) (winerr error) = ntdll.RtlNtStatusToDosErrorNoTeb +//sys rtlDosPathNameToNtPathName(name *uint16, ntName *unicodeString, filePart uintptr, reserved uintptr) (status ntstatus) = ntdll.RtlDosPathNameToNtPathName_U +//sys rtlDefaultNpAcl(dacl *uintptr) (status ntstatus) = ntdll.RtlDefaultNpAcl + +type ioStatusBlock struct { + Status, Information uintptr +} + +type objectAttributes struct { + Length uintptr + RootDirectory uintptr + ObjectName *unicodeString + Attributes uintptr + SecurityDescriptor *securityDescriptor + SecurityQoS uintptr +} + +type unicodeString struct { + Length uint16 + MaximumLength uint16 + Buffer uintptr +} + +type securityDescriptor struct { + Revision byte + Sbz1 byte + Control uint16 + Owner uintptr + Group uintptr + Sacl uintptr + Dacl uintptr +} + +type ntstatus int32 + +func (status ntstatus) Err() error { + if status >= 0 { + return nil + } + return rtlNtStatusToDosError(status) +} + +const ( + cERROR_PIPE_BUSY = syscall.Errno(231) + cERROR_NO_DATA = syscall.Errno(232) + cERROR_PIPE_CONNECTED = syscall.Errno(535) + cERROR_SEM_TIMEOUT = syscall.Errno(121) + + cSECURITY_SQOS_PRESENT = 0x100000 + cSECURITY_ANONYMOUS = 0 + + cPIPE_TYPE_MESSAGE = 4 + + cPIPE_READMODE_MESSAGE = 2 + + cFILE_OPEN = 1 + cFILE_CREATE = 2 + + cFILE_PIPE_MESSAGE_TYPE = 1 + cFILE_PIPE_REJECT_REMOTE_CLIENTS = 2 + + cSE_DACL_PRESENT = 4 +) + +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 + } else if err == syscall.ERROR_MORE_DATA { + // ERROR_MORE_DATA indicates that the pipe's read mode is message mode + // and the message still has more bytes. Treat this as a success, since + // this package presents all named pipes as byte streams. + err = nil + } + return n, err +} + +func (s pipeAddress) Network() string { + return "pipe" +} + +func (s pipeAddress) String() string { + return string(s) +} + +// tryDialPipe attempts to dial the pipe at `path` until `ctx` cancellation or timeout. +func tryDialPipe(ctx context.Context, path *string) (syscall.Handle, error) { + for { + select { + case <-ctx.Done(): + return syscall.Handle(0), ctx.Err() + default: + 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 == nil { + return h, nil + } + if err != cERROR_PIPE_BUSY { + return h, &os.PathError{Err: err, Op: "open", Path: *path} + } + // Wait 10 msec and try again. This is a rather simplistic + // view, as we always try each 10 milliseconds. + time.Sleep(time.Millisecond * 10) + } + } +} + +// DialPipe connects to a named pipe by path, timing out if the connection +// takes longer than the specified duration. If timeout is nil, then we use +// a default timeout of 2 seconds. (We do not use WaitNamedPipe.) +func DialPipe(path string, timeout *time.Duration) (net.Conn, error) { + var absTimeout time.Time + if timeout != nil { + absTimeout = time.Now().Add(*timeout) + } else { + absTimeout = time.Now().Add(time.Second * 2) + } + ctx, _ := context.WithDeadline(context.Background(), absTimeout) + conn, err := DialPipeContext(ctx, path) + if err == context.DeadlineExceeded { + return nil, ErrTimeout + } + return conn, err +} + +// DialPipeContext attempts to connect to a named pipe by `path` until `ctx` +// cancellation or timeout. +func DialPipeContext(ctx context.Context, path string) (net.Conn, error) { + var err error + var h syscall.Handle + h, err = tryDialPipe(ctx, &path) + if err != nil { + return nil, err + } + + var flags uint32 + err = getNamedPipeInfo(h, &flags, nil, nil, nil) + if err != nil { + return nil, err + } + + 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 + config PipeConfig + acceptCh chan (chan acceptResponse) + closeCh chan int + doneCh chan int +} + +func makeServerPipeHandle(path string, sd []byte, c *PipeConfig, first bool) (syscall.Handle, error) { + path16, err := syscall.UTF16FromString(path) + if err != nil { + return 0, &os.PathError{Op: "open", Path: path, Err: err} + } + + var oa objectAttributes + oa.Length = unsafe.Sizeof(oa) + + var ntPath unicodeString + if err := rtlDosPathNameToNtPathName(&path16[0], &ntPath, 0, 0).Err(); err != nil { + return 0, &os.PathError{Op: "open", Path: path, Err: err} + } + defer localFree(ntPath.Buffer) + oa.ObjectName = &ntPath + + // The security descriptor is only needed for the first pipe. + if first { + if sd != nil { + len := uint32(len(sd)) + sdb := localAlloc(0, len) + defer localFree(sdb) + copy((*[0xffff]byte)(unsafe.Pointer(sdb))[:], sd) + oa.SecurityDescriptor = (*securityDescriptor)(unsafe.Pointer(sdb)) + } else { + // Construct the default named pipe security descriptor. + var dacl uintptr + if err := rtlDefaultNpAcl(&dacl).Err(); err != nil { + return 0, fmt.Errorf("getting default named pipe ACL: %s", err) + } + defer localFree(dacl) + + sdb := &securityDescriptor{ + Revision: 1, + Control: cSE_DACL_PRESENT, + Dacl: dacl, + } + oa.SecurityDescriptor = sdb + } + } + + typ := uint32(cFILE_PIPE_REJECT_REMOTE_CLIENTS) + if c.MessageMode { + typ |= cFILE_PIPE_MESSAGE_TYPE + } + + disposition := uint32(cFILE_OPEN) + access := uint32(syscall.GENERIC_READ | syscall.GENERIC_WRITE | syscall.SYNCHRONIZE) + if first { + disposition = cFILE_CREATE + // By not asking for read or write access, the named pipe file system + // will put this pipe into an initially disconnected state, blocking + // client connections until the next call with first == false. + access = syscall.SYNCHRONIZE + } + + timeout := int64(-50 * 10000) // 50ms + + var ( + h syscall.Handle + iosb ioStatusBlock + ) + err = ntCreateNamedPipeFile(&h, access, &oa, &iosb, syscall.FILE_SHARE_READ|syscall.FILE_SHARE_WRITE, disposition, 0, typ, 0, 0, 0xffffffff, uint32(c.InputBufferSize), uint32(c.OutputBufferSize), &timeout).Err() + if err != nil { + return 0, &os.PathError{Op: "open", Path: path, Err: err} + } + + runtime.KeepAlive(ntPath) + return h, nil +} + +func (l *win32PipeListener) makeServerPipe() (*win32File, error) { + h, err := makeServerPipeHandle(l.path, nil, &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) makeConnectedServerPipe() (*win32File, error) { + p, err := l.makeServerPipe() + if err != nil { + return nil, err + } + + // 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 + } + } + return p, err +} + +func (l *win32PipeListener) listenerRoutine() { + closed := false + for !closed { + select { + case <-l.closeCh: + closed = true + case responseCh := <-l.acceptCh: + var ( + p *win32File + err error + ) + for { + p, err = l.makeConnectedServerPipe() + // If the connection was immediately closed by the client, try + // again. + if err != cERROR_NO_DATA { + break + } + } + responseCh <- acceptResponse{p, err} + closed = err == ErrPipeListenerClosed + } + } + 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 + } + l := &win32PipeListener{ + firstHandle: h, + path: path, + 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) +} |