Windows Shell Items (AKA "shellbags") is an undocumented set of structures used internally within Windows to identify paths in Windows Folder Hierarchy. It is widely used in Windows Shell (and most visible in File Explorer), both as in-memory and in-file structures. Some formats embed them, namely:
The format is mostly undocumented, and is known to vary between various Windows versions.
This page hosts a formal specification of Windows Shell Items using Kaitai Struct. This specification can be automatically translated into a variety of programming languages to get a parsing library.
# This is a generated file! Please edit source .ksy file and use kaitai-struct-compiler to rebuild
# type: ignore
import kaitaistruct
from kaitaistruct import ReadWriteKaitaiStruct, KaitaiStream, BytesIO
if getattr(kaitaistruct, 'API_VERSION', (0, 9)) < (0, 11):
raise Exception("Incompatible Kaitai Struct Python API: 0.11 or later is required, but you have %s" % (kaitaistruct.__version__))
class WindowsShellItems(ReadWriteKaitaiStruct):
"""Windows Shell Items (AKA "shellbags") is an undocumented set of
structures used internally within Windows to identify paths in
Windows Folder Hierarchy. It is widely used in Windows Shell (and
most visible in File Explorer), both as in-memory and in-file
structures. Some formats embed them, namely:
* Windows Shell link files (.lnk) Windows registry
* Windows registry "ShellBags" keys
The format is mostly undocumented, and is known to vary between
various Windows versions.
.. seealso::
Source - https://github.com/libyal/libfwsi/blob/main/documentation/Windows%20Shell%20Item%20format.asciidoc
"""
def __init__(self, _io=None, _parent=None, _root=None):
super(WindowsShellItems, self).__init__(_io)
self._parent = _parent
self._root = _root or self
def _read(self):
self.items = []
i = 0
while True:
_t_items = WindowsShellItems.ShellItem(self._io, self, self._root)
try:
_t_items._read()
finally:
_ = _t_items
self.items.append(_)
if _.len_data == 0:
break
i += 1
self._dirty = False
def _fetch_instances(self):
pass
for i in range(len(self.items)):
pass
self.items[i]._fetch_instances()
def _write__seq(self, io=None):
super(WindowsShellItems, self)._write__seq(io)
for i in range(len(self.items)):
pass
self.items[i]._write__seq(self._io)
def _check(self):
if len(self.items) == 0:
raise kaitaistruct.ConsistencyError(u"items", 0, len(self.items))
for i in range(len(self.items)):
pass
if self.items[i]._root != self._root:
raise kaitaistruct.ConsistencyError(u"items", self._root, self.items[i]._root)
if self.items[i]._parent != self:
raise kaitaistruct.ConsistencyError(u"items", self, self.items[i]._parent)
_ = self.items[i]
if (_.len_data == 0) != (i == len(self.items) - 1):
raise kaitaistruct.ConsistencyError(u"items", i == len(self.items) - 1, _.len_data == 0)
self._dirty = False
class FileEntryBody(ReadWriteKaitaiStruct):
"""
.. seealso::
Source - https://github.com/libyal/libfwsi/blob/main/documentation/Windows%20Shell%20Item%20format.asciidoc#34-file-entry-shell-item
"""
def __init__(self, _io=None, _parent=None, _root=None):
super(WindowsShellItems.FileEntryBody, self).__init__(_io)
self._parent = _parent
self._root = _root
def _read(self):
self._unnamed0 = self._io.read_u1()
self.file_size = self._io.read_u4le()
self.last_mod_time = self._io.read_u4le()
self.file_attrs = self._io.read_u2le()
self._dirty = False
def _fetch_instances(self):
pass
def _write__seq(self, io=None):
super(WindowsShellItems.FileEntryBody, self)._write__seq(io)
self._io.write_u1(self._unnamed0)
self._io.write_u4le(self.file_size)
self._io.write_u4le(self.last_mod_time)
self._io.write_u2le(self.file_attrs)
def _check(self):
self._dirty = False
@property
def is_dir(self):
if hasattr(self, '_m_is_dir'):
return self._m_is_dir
self._m_is_dir = self._parent.code & 1 != 0
return getattr(self, '_m_is_dir', None)
def _invalidate_is_dir(self):
del self._m_is_dir
@property
def is_file(self):
if hasattr(self, '_m_is_file'):
return self._m_is_file
self._m_is_file = self._parent.code & 2 != 0
return getattr(self, '_m_is_file', None)
def _invalidate_is_file(self):
del self._m_is_file
class RootFolderBody(ReadWriteKaitaiStruct):
"""
.. seealso::
Source - https://github.com/libyal/libfwsi/blob/main/documentation/Windows%20Shell%20Item%20format.asciidoc#32-root-folder-shell-item
"""
def __init__(self, _io=None, _parent=None, _root=None):
super(WindowsShellItems.RootFolderBody, self).__init__(_io)
self._parent = _parent
self._root = _root
def _read(self):
self.sort_index = self._io.read_u1()
self.shell_folder_id = self._io.read_bytes(16)
self._dirty = False
def _fetch_instances(self):
pass
def _write__seq(self, io=None):
super(WindowsShellItems.RootFolderBody, self)._write__seq(io)
self._io.write_u1(self.sort_index)
self._io.write_bytes(self.shell_folder_id)
def _check(self):
if len(self.shell_folder_id) != 16:
raise kaitaistruct.ConsistencyError(u"shell_folder_id", 16, len(self.shell_folder_id))
self._dirty = False
class ShellItem(ReadWriteKaitaiStruct):
"""
.. seealso::
Section 2.2.2 - https://winprotocoldoc.blob.core.windows.net/productionwindowsarchives/MS-SHLLINK/[MS-SHLLINK].pdf
"""
def __init__(self, _io=None, _parent=None, _root=None):
super(WindowsShellItems.ShellItem, self).__init__(_io)
self._parent = _parent
self._root = _root
def _read(self):
self.len_data = self._io.read_u2le()
if self.len_data >= 2:
pass
self._raw_data = self._io.read_bytes(self.len_data - 2)
_io__raw_data = KaitaiStream(BytesIO(self._raw_data))
self.data = WindowsShellItems.ShellItemData(_io__raw_data, self, self._root)
self.data._read()
self._dirty = False
def _fetch_instances(self):
pass
if self.len_data >= 2:
pass
self.data._fetch_instances()
def _write__seq(self, io=None):
super(WindowsShellItems.ShellItem, self)._write__seq(io)
self._io.write_u2le(self.len_data)
if self.len_data >= 2:
pass
_io__raw_data = KaitaiStream(BytesIO(bytearray(self.len_data - 2)))
self._io.add_child_stream(_io__raw_data)
_pos2 = self._io.pos()
self._io.seek(self._io.pos() + (self.len_data - 2))
def handler(parent, _io__raw_data=_io__raw_data):
self._raw_data = _io__raw_data.to_byte_array()
if len(self._raw_data) != self.len_data - 2:
raise kaitaistruct.ConsistencyError(u"raw(data)", self.len_data - 2, len(self._raw_data))
parent.write_bytes(self._raw_data)
_io__raw_data.write_back_handler = KaitaiStream.WriteBackHandler(_pos2, handler)
self.data._write__seq(_io__raw_data)
def _check(self):
if self.len_data >= 2:
pass
if self.data._root != self._root:
raise kaitaistruct.ConsistencyError(u"data", self._root, self.data._root)
if self.data._parent != self:
raise kaitaistruct.ConsistencyError(u"data", self, self.data._parent)
self._dirty = False
class ShellItemData(ReadWriteKaitaiStruct):
def __init__(self, _io=None, _parent=None, _root=None):
super(WindowsShellItems.ShellItemData, self).__init__(_io)
self._parent = _parent
self._root = _root
def _read(self):
self.code = self._io.read_u1()
_on = self.code
if _on == 31:
pass
self.body1 = WindowsShellItems.RootFolderBody(self._io, self, self._root)
self.body1._read()
_on = self.code & 112
if _on == 32:
pass
self.body2 = WindowsShellItems.VolumeBody(self._io, self, self._root)
self.body2._read()
elif _on == 48:
pass
self.body2 = WindowsShellItems.FileEntryBody(self._io, self, self._root)
self.body2._read()
self._dirty = False
def _fetch_instances(self):
pass
_on = self.code
if _on == 31:
pass
self.body1._fetch_instances()
_on = self.code & 112
if _on == 32:
pass
self.body2._fetch_instances()
elif _on == 48:
pass
self.body2._fetch_instances()
def _write__seq(self, io=None):
super(WindowsShellItems.ShellItemData, self)._write__seq(io)
self._io.write_u1(self.code)
_on = self.code
if _on == 31:
pass
self.body1._write__seq(self._io)
_on = self.code & 112
if _on == 32:
pass
self.body2._write__seq(self._io)
elif _on == 48:
pass
self.body2._write__seq(self._io)
def _check(self):
_on = self.code
if _on == 31:
pass
if self.body1._root != self._root:
raise kaitaistruct.ConsistencyError(u"body1", self._root, self.body1._root)
if self.body1._parent != self:
raise kaitaistruct.ConsistencyError(u"body1", self, self.body1._parent)
_on = self.code & 112
if _on == 32:
pass
if self.body2._root != self._root:
raise kaitaistruct.ConsistencyError(u"body2", self._root, self.body2._root)
if self.body2._parent != self:
raise kaitaistruct.ConsistencyError(u"body2", self, self.body2._parent)
elif _on == 48:
pass
if self.body2._root != self._root:
raise kaitaistruct.ConsistencyError(u"body2", self._root, self.body2._root)
if self.body2._parent != self:
raise kaitaistruct.ConsistencyError(u"body2", self, self.body2._parent)
self._dirty = False
class VolumeBody(ReadWriteKaitaiStruct):
"""
.. seealso::
Source - https://github.com/libyal/libfwsi/blob/main/documentation/Windows%20Shell%20Item%20format.asciidoc#33-volume-shell-item
"""
def __init__(self, _io=None, _parent=None, _root=None):
super(WindowsShellItems.VolumeBody, self).__init__(_io)
self._parent = _parent
self._root = _root
def _read(self):
self.flags = self._io.read_u1()
self._dirty = False
def _fetch_instances(self):
pass
def _write__seq(self, io=None):
super(WindowsShellItems.VolumeBody, self)._write__seq(io)
self._io.write_u1(self.flags)
def _check(self):
self._dirty = False