README
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go-winio
This repository contains utilities for efficiently performing Win32 IO operations in Go. Currently, this is focused on accessing named pipes and other file handles, and for using named pipes as a net transport.
This code relies on IO completion ports to avoid blocking IO on system threads, allowing Go to reuse the thread to schedule another goroutine. This limits support to Windows Vista and newer operating systems. This is similar to the implementation of network sockets in Go's net package.
Please see the LICENSE file for licensing information.
Thanks to natefinch for the inspiration for this library. See https://github.com/natefinch/npipe for another named pipe implementation.
Documentation
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Index ¶
- Constants
- Variables
- func DialPipe(path string, timeout *time.Duration) (net.Conn, error)
- func EncodeReparsePoint(rp *ReparsePoint) []byte
- func ListenPipe(path string, c *PipeConfig) (net.Listener, error)
- func LookupSidByName(name string) (sid string, err error)
- func MakeOpenFile(h syscall.Handle) (io.ReadWriteCloser, error)
- func OpenForBackup(path string, access uint32, share uint32, createmode uint32) (*os.File, error)
- func RunWithPrivilege(name string, fn func() error) error
- func RunWithPrivileges(names []string, fn func() error) error
- func SddlToSecurityDescriptor(sddl string) ([]byte, error)
- func SecurityDescriptorToSddl(sd []byte) (string, error)
- func SetFileBasicInfo(f *os.File, bi *FileBasicInfo) error
- type AccountLookupError
- type BackupFileReader
- type BackupFileWriter
- type BackupHeader
- type BackupStreamReader
- type BackupStreamWriter
- type FileBasicInfo
- type FileIDInfo
- type PipeConfig
- type PrivilegeError
- type ReparsePoint
- type SddlConversionError
- type UnsupportedReparsePointError
Constants ¶
const ( BackupData = uint32(iota + 1) BackupEaData BackupSecurity BackupAlternateData BackupLink BackupPropertyData BackupObjectId BackupReparseData BackupSparseBlock BackupTxfsData )
const ( WRITE_DAC = 0x40000 WRITE_OWNER = 0x80000 ACCESS_SYSTEM_SECURITY = 0x1000000 )
const ( SE_PRIVILEGE_ENABLED = 2 ERROR_NOT_ALL_ASSIGNED syscall.Errno = 1300 SeBackupPrivilege = "SeBackupPrivilege" SeRestorePrivilege = "SeRestorePrivilege" )
const (
StreamSparseAttributes = uint32(8)
)
Variables ¶
var ( ErrFileClosed = errors.New("file has already been closed") ErrTimeout = &timeoutError{} )
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") )
Functions ¶
func DialPipe ¶
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 EncodeReparsePoint ¶
func EncodeReparsePoint(rp *ReparsePoint) []byte
EncodeReparsePoint encodes a Win32 REPARSE_DATA_BUFFER structure describing a symlink or mount point.
func ListenPipe ¶
func ListenPipe(path string, c *PipeConfig) (net.Listener, error)
ListenPipe creates a listener on a Windows named pipe path, e.g. \\.\pipe\mypipe. The pipe must not already exist.
func LookupSidByName ¶
LookupSidByName looks up the SID of an account by name
func MakeOpenFile ¶
func MakeOpenFile(h syscall.Handle) (io.ReadWriteCloser, error)
func OpenForBackup ¶
OpenForBackup opens a file or directory, potentially skipping access checks if the backup or restore privileges have been acquired.
If the file opened was a directory, it cannot be used with Readdir().
func RunWithPrivilege ¶
func RunWithPrivileges ¶
func SetFileBasicInfo ¶
func SetFileBasicInfo(f *os.File, bi *FileBasicInfo) error
SetFileBasicInfo sets times and attributes for a file.
Types ¶
type AccountLookupError ¶
func (*AccountLookupError) Error ¶
func (e *AccountLookupError) Error() string
type BackupFileReader ¶
type BackupFileReader struct {
// contains filtered or unexported fields
}
BackupFileReader provides an io.ReadCloser interface on top of the BackupRead Win32 API.
func NewBackupFileReader ¶
func NewBackupFileReader(f *os.File, includeSecurity bool) *BackupFileReader
NewBackupFileReader returns a new BackupFileReader from a file handle. If includeSecurity is true, Read will attempt to read the security descriptor of the file.
func (*BackupFileReader) Close ¶
func (r *BackupFileReader) Close() error
Close frees Win32 resources associated with the BackupFileReader. It does not close the underlying file.
type BackupFileWriter ¶
type BackupFileWriter struct {
// contains filtered or unexported fields
}
BackupFileWriter provides an io.WriteCloser interface on top of the BackupWrite Win32 API.
func NewBackupFileWriter ¶
func NewBackupFileWriter(f *os.File, includeSecurity bool) *BackupFileWriter
NewBackupFileWrtier returns a new BackupFileWriter from a file handle. If includeSecurity is true, Write() will attempt to restore the security descriptor from the stream.
func (*BackupFileWriter) Close ¶
func (w *BackupFileWriter) Close() error
Close frees Win32 resources associated with the BackupFileWriter. It does not close the underlying file.
type BackupHeader ¶
type BackupHeader struct {
Id uint32 // The backup stream ID
Attributes uint32 // Stream attributes
Size int64 // The size of the stream in bytes
Name string // The name of the stream (for BackupAlternateData only).
Offset int64 // The offset of the stream in the file (for BackupSparseBlock only).
}
BackupHeader represents a backup stream of a file.
type BackupStreamReader ¶
type BackupStreamReader struct {
// contains filtered or unexported fields
}
BackupStreamReader reads from a stream produced by the BackupRead Win32 API and produces a series of BackupHeader values.
func NewBackupStreamReader ¶
func NewBackupStreamReader(r io.Reader) *BackupStreamReader
NewBackupStreamReader produces a BackupStreamReader from any io.Reader.
func (*BackupStreamReader) Next ¶
func (r *BackupStreamReader) Next() (*BackupHeader, error)
Next returns the next backup stream and prepares for calls to Write(). It skips the remainder of the current stream if it was not completely read.
type BackupStreamWriter ¶
type BackupStreamWriter struct {
// contains filtered or unexported fields
}
BackupStreamWriter writes a stream compatible with the BackupWrite Win32 API.
func NewBackupStreamWriter ¶
func NewBackupStreamWriter(w io.Writer) *BackupStreamWriter
NewBackupStreamWriter produces a BackupStreamWriter on top of an io.Writer.
func (*BackupStreamWriter) Write ¶
func (w *BackupStreamWriter) Write(b []byte) (int, error)
Write writes to the current backup stream.
func (*BackupStreamWriter) WriteHeader ¶
func (w *BackupStreamWriter) WriteHeader(hdr *BackupHeader) error
WriteHeader writes the next backup stream header and prepares for calls to Write().
type FileBasicInfo ¶
type FileBasicInfo struct {
CreationTime, LastAccessTime, LastWriteTime, ChangeTime syscall.Filetime
FileAttributes uintptr // includes padding
}
FileBasicInfo contains file access time and file attributes information.
func GetFileBasicInfo ¶
func GetFileBasicInfo(f *os.File) (*FileBasicInfo, error)
GetFileBasicInfo retrieves times and attributes for a file.
type FileIDInfo ¶
FileIDInfo contains the volume serial number and file ID for a file. This pair should be unique on a system.
type PipeConfig ¶
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
}
PipeConfig contain configuration for the pipe listener.
type PrivilegeError ¶
type PrivilegeError struct {
// contains filtered or unexported fields
}
func (*PrivilegeError) Error ¶
func (e *PrivilegeError) Error() string
type ReparsePoint ¶
ReparsePoint describes a Win32 symlink or mount point.
func DecodeReparsePoint ¶
func DecodeReparsePoint(b []byte) (*ReparsePoint, error)
DecodeReparsePoint decodes a Win32 REPARSE_DATA_BUFFER structure containing either a symlink or a mount point.
type SddlConversionError ¶
func (*SddlConversionError) Error ¶
func (e *SddlConversionError) Error() string
type UnsupportedReparsePointError ¶
type UnsupportedReparsePointError struct {
Tag uint32
}
UnsupportedReparsePointError is returned when trying to decode a non-symlink or mount point reparse point.
func (*UnsupportedReparsePointError) Error ¶
func (e *UnsupportedReparsePointError) Error() string
Source Files