diff options
Diffstat (limited to 'vendor/github.com/Microsoft/go-winio/pipe.go')
| -rw-r--r-- | vendor/github.com/Microsoft/go-winio/pipe.go | 231 |
1 files changed, 160 insertions, 71 deletions
diff --git a/vendor/github.com/Microsoft/go-winio/pipe.go b/vendor/github.com/Microsoft/go-winio/pipe.go index d99eedb64..d6a46f6a2 100644 --- a/vendor/github.com/Microsoft/go-winio/pipe.go +++ b/vendor/github.com/Microsoft/go-winio/pipe.go @@ -3,10 +3,13 @@ package winio import ( + "context" "errors" + "fmt" "io" "net" "os" + "runtime" "syscall" "time" "unsafe" @@ -18,6 +21,48 @@ import ( //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) @@ -25,21 +70,20 @@ const ( 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 + cSECURITY_SQOS_PRESENT = 0x100000 + cSECURITY_ANONYMOUS = 0 - cPIPE_REJECT_REMOTE_CLIENTS = 0x8 + cPIPE_TYPE_MESSAGE = 4 - cPIPE_UNLIMITED_INSTANCES = 255 + cPIPE_READMODE_MESSAGE = 2 - cNMPWAIT_USE_DEFAULT_WAIT = 0 - cNMPWAIT_NOWAIT = 1 + cFILE_OPEN = 1 + cFILE_CREATE = 2 - cPIPE_TYPE_MESSAGE = 4 + cFILE_PIPE_MESSAGE_TYPE = 1 + cFILE_PIPE_REJECT_REMOTE_CLIENTS = 2 - cPIPE_READMODE_MESSAGE = 2 + cSE_DACL_PRESENT = 4 ) var ( @@ -137,9 +181,30 @@ 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 5 seconds. (We do not use WaitNamedPipe.) +// 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 { @@ -147,23 +212,22 @@ func DialPipe(path string, timeout *time.Duration) (net.Conn, error) { } 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 - 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 - } - if time.Now().After(absTimeout) { - return nil, ErrTimeout - } - - // Wait 10 msec and try again. This is a rather simplistic - // view, as we always try each 10 milliseconds. - time.Sleep(time.Millisecond * 10) - } + h, err = tryDialPipe(ctx, &path) if err != nil { - return nil, &os.PathError{Op: "open", Path: path, Err: err} + return nil, err } var flags uint32 @@ -194,43 +258,87 @@ type acceptResponse struct { } type win32PipeListener struct { - firstHandle syscall.Handle - path string - securityDescriptor []byte - config PipeConfig - acceptCh chan (chan acceptResponse) - closeCh chan int - doneCh chan int + firstHandle syscall.Handle + path string + 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 +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 { - flags |= cFILE_FLAG_FIRST_PIPE_INSTANCE + 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 + } } - var mode uint32 = cPIPE_REJECT_REMOTE_CLIENTS + typ := uint32(cFILE_PIPE_REJECT_REMOTE_CLIENTS) if c.MessageMode { - mode |= cPIPE_TYPE_MESSAGE + typ |= cFILE_PIPE_MESSAGE_TYPE } - 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) + 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 } - h, err := createNamedPipe(path, flags, mode, cPIPE_UNLIMITED_INSTANCES, uint32(c.OutputBufferSize), uint32(c.InputBufferSize), 0, sa) + + 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, l.securityDescriptor, &l.config, false) + h, err := makeServerPipeHandle(l.path, nil, &l.config, false) if err != nil { return nil, err } @@ -341,32 +449,13 @@ func ListenPipe(path string, c *PipeConfig) (net.Listener, error) { if err != nil { return nil, err } - // Create a client handle and connect it. This results in the pipe - // instance always existing, so that clients see ERROR_PIPE_BUSY - // rather than ERROR_FILE_NOT_FOUND. This ties the first instance - // up so that no other instances can be used. This would have been - // cleaner if the Win32 API matched CreateFile with ConnectNamedPipe - // instead of CreateNamedPipe. (Apparently created named pipes are - // considered to be in listening state regardless of whether any - // active calls to ConnectNamedPipe are outstanding.) - 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 - } - // Close the client handle. The server side of the instance will - // still be busy, leading to ERROR_PIPE_BUSY instead of - // ERROR_NOT_FOUND, as long as we don't close the server handle, - // or disconnect the client with DisconnectNamedPipe. - 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), + 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 |