moby/pkg/system/filesys_windows.go
Sebastiaan van Stijn 509f19f611
replace pkg/system Sequential funcs with moby/sys/sequential
Migrating these functions to allow them being shared between moby, docker/cli,
and containerd, and to allow using them without importing all of sys / system,
which (in containerd) also depends on hcsshim and more.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
2022-08-30 09:33:49 +02:00

118 lines
3.1 KiB
Go

package system // import "github.com/docker/docker/pkg/system"
import (
"os"
"regexp"
"syscall"
"unsafe"
"golang.org/x/sys/windows"
)
const (
// SddlAdministratorsLocalSystem is local administrators plus NT AUTHORITY\System
SddlAdministratorsLocalSystem = "D:P(A;OICI;GA;;;BA)(A;OICI;GA;;;SY)"
)
// MkdirAllWithACL is a wrapper for MkdirAll that creates a directory
// with an appropriate SDDL defined ACL.
func MkdirAllWithACL(path string, perm os.FileMode, sddl string) error {
return mkdirall(path, true, sddl)
}
// MkdirAll implementation that is volume path aware for Windows. It can be used
// as a drop-in replacement for os.MkdirAll()
func MkdirAll(path string, _ os.FileMode) error {
return mkdirall(path, false, "")
}
// mkdirall is a custom version of os.MkdirAll modified for use on Windows
// so that it is both volume path aware, and can create a directory with
// a DACL.
func mkdirall(path string, applyACL bool, sddl string) error {
if re := regexp.MustCompile(`^\\\\\?\\Volume{[a-z0-9-]+}$`); re.MatchString(path) {
return nil
}
// The rest of this method is largely copied from os.MkdirAll and should be kept
// as-is to ensure compatibility.
// Fast path: if we can tell whether path is a directory or file, stop with success or error.
dir, err := os.Stat(path)
if err == nil {
if dir.IsDir() {
return nil
}
return &os.PathError{
Op: "mkdir",
Path: path,
Err: syscall.ENOTDIR,
}
}
// Slow path: make sure parent exists and then call Mkdir for path.
i := len(path)
for i > 0 && os.IsPathSeparator(path[i-1]) { // Skip trailing path separator.
i--
}
j := i
for j > 0 && !os.IsPathSeparator(path[j-1]) { // Scan backward over element.
j--
}
if j > 1 {
// Create parent
err = mkdirall(path[0:j-1], false, sddl)
if err != nil {
return err
}
}
// Parent now exists; invoke os.Mkdir or mkdirWithACL and use its result.
if applyACL {
err = mkdirWithACL(path, sddl)
} else {
err = os.Mkdir(path, 0)
}
if err != nil {
// Handle arguments like "foo/." by
// double-checking that directory doesn't exist.
dir, err1 := os.Lstat(path)
if err1 == nil && dir.IsDir() {
return nil
}
return err
}
return nil
}
// mkdirWithACL creates a new directory. If there is an error, it will be of
// type *PathError. .
//
// This is a modified and combined version of os.Mkdir and windows.Mkdir
// in golang to cater for creating a directory am ACL permitting full
// access, with inheritance, to any subfolder/file for Built-in Administrators
// and Local System.
func mkdirWithACL(name string, sddl string) error {
sa := windows.SecurityAttributes{Length: 0}
sd, err := windows.SecurityDescriptorFromString(sddl)
if err != nil {
return &os.PathError{Op: "mkdir", Path: name, Err: err}
}
sa.Length = uint32(unsafe.Sizeof(sa))
sa.InheritHandle = 1
sa.SecurityDescriptor = sd
namep, err := windows.UTF16PtrFromString(name)
if err != nil {
return &os.PathError{Op: "mkdir", Path: name, Err: err}
}
e := windows.CreateDirectory(namep, &sa)
if e != nil {
return &os.PathError{Op: "mkdir", Path: name, Err: e}
}
return nil
}