986f076276
Add a new generic container registry client via a new `container` package. Use this to create a command line utility as well as a new upload target for container registries. The code uses the github.com/containers/* project and packages to interact with container registires that is also used by skopeo, podman et al. One if the dependencies is `proglottis/gpgme` that is using cgo to bind libgpgme, so we have to add the corresponding devel package to the BuildRequires as well as installing it on CI. Checks will follow later via an integration test.
128 lines
3.4 KiB
Go
128 lines
3.4 KiB
Go
package winio
|
|
|
|
import (
|
|
"bytes"
|
|
"encoding/binary"
|
|
"fmt"
|
|
"strings"
|
|
"unicode/utf16"
|
|
"unsafe"
|
|
)
|
|
|
|
const (
|
|
reparseTagMountPoint = 0xA0000003
|
|
reparseTagSymlink = 0xA000000C
|
|
)
|
|
|
|
type reparseDataBuffer struct {
|
|
ReparseTag uint32
|
|
ReparseDataLength uint16
|
|
Reserved uint16
|
|
SubstituteNameOffset uint16
|
|
SubstituteNameLength uint16
|
|
PrintNameOffset uint16
|
|
PrintNameLength uint16
|
|
}
|
|
|
|
// ReparsePoint describes a Win32 symlink or mount point.
|
|
type ReparsePoint struct {
|
|
Target string
|
|
IsMountPoint bool
|
|
}
|
|
|
|
// UnsupportedReparsePointError is returned when trying to decode a non-symlink or
|
|
// mount point reparse point.
|
|
type UnsupportedReparsePointError struct {
|
|
Tag uint32
|
|
}
|
|
|
|
func (e *UnsupportedReparsePointError) Error() string {
|
|
return fmt.Sprintf("unsupported reparse point %x", e.Tag)
|
|
}
|
|
|
|
// DecodeReparsePoint decodes a Win32 REPARSE_DATA_BUFFER structure containing either a symlink
|
|
// or a mount point.
|
|
func DecodeReparsePoint(b []byte) (*ReparsePoint, error) {
|
|
tag := binary.LittleEndian.Uint32(b[0:4])
|
|
return DecodeReparsePointData(tag, b[8:])
|
|
}
|
|
|
|
func DecodeReparsePointData(tag uint32, b []byte) (*ReparsePoint, error) {
|
|
isMountPoint := false
|
|
switch tag {
|
|
case reparseTagMountPoint:
|
|
isMountPoint = true
|
|
case reparseTagSymlink:
|
|
default:
|
|
return nil, &UnsupportedReparsePointError{tag}
|
|
}
|
|
nameOffset := 8 + binary.LittleEndian.Uint16(b[4:6])
|
|
if !isMountPoint {
|
|
nameOffset += 4
|
|
}
|
|
nameLength := binary.LittleEndian.Uint16(b[6:8])
|
|
name := make([]uint16, nameLength/2)
|
|
err := binary.Read(bytes.NewReader(b[nameOffset:nameOffset+nameLength]), binary.LittleEndian, &name)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return &ReparsePoint{string(utf16.Decode(name)), isMountPoint}, nil
|
|
}
|
|
|
|
func isDriveLetter(c byte) bool {
|
|
return (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z')
|
|
}
|
|
|
|
// EncodeReparsePoint encodes a Win32 REPARSE_DATA_BUFFER structure describing a symlink or
|
|
// mount point.
|
|
func EncodeReparsePoint(rp *ReparsePoint) []byte {
|
|
// Generate an NT path and determine if this is a relative path.
|
|
var ntTarget string
|
|
relative := false
|
|
if strings.HasPrefix(rp.Target, `\\?\`) {
|
|
ntTarget = `\??\` + rp.Target[4:]
|
|
} else if strings.HasPrefix(rp.Target, `\\`) {
|
|
ntTarget = `\??\UNC\` + rp.Target[2:]
|
|
} else if len(rp.Target) >= 2 && isDriveLetter(rp.Target[0]) && rp.Target[1] == ':' {
|
|
ntTarget = `\??\` + rp.Target
|
|
} else {
|
|
ntTarget = rp.Target
|
|
relative = true
|
|
}
|
|
|
|
// The paths must be NUL-terminated even though they are counted strings.
|
|
target16 := utf16.Encode([]rune(rp.Target + "\x00"))
|
|
ntTarget16 := utf16.Encode([]rune(ntTarget + "\x00"))
|
|
|
|
size := int(unsafe.Sizeof(reparseDataBuffer{})) - 8
|
|
size += len(ntTarget16)*2 + len(target16)*2
|
|
|
|
tag := uint32(reparseTagMountPoint)
|
|
if !rp.IsMountPoint {
|
|
tag = reparseTagSymlink
|
|
size += 4 // Add room for symlink flags
|
|
}
|
|
|
|
data := reparseDataBuffer{
|
|
ReparseTag: tag,
|
|
ReparseDataLength: uint16(size),
|
|
SubstituteNameOffset: 0,
|
|
SubstituteNameLength: uint16((len(ntTarget16) - 1) * 2),
|
|
PrintNameOffset: uint16(len(ntTarget16) * 2),
|
|
PrintNameLength: uint16((len(target16) - 1) * 2),
|
|
}
|
|
|
|
var b bytes.Buffer
|
|
binary.Write(&b, binary.LittleEndian, &data)
|
|
if !rp.IsMountPoint {
|
|
flags := uint32(0)
|
|
if relative {
|
|
flags |= 1
|
|
}
|
|
binary.Write(&b, binary.LittleEndian, flags)
|
|
}
|
|
|
|
binary.Write(&b, binary.LittleEndian, ntTarget16)
|
|
binary.Write(&b, binary.LittleEndian, target16)
|
|
return b.Bytes()
|
|
}
|