PIL.OleFileIO 源代码

#!/usr/bin/env python

# olefile (formerly OleFileIO_PL) version 0.42 2015-01-25
#
# Module to read/write Microsoft OLE2 files (also called Structured Storage or
# Microsoft Compound Document File Format), such as Microsoft Office 97-2003
# documents, Image Composer and FlashPix files, Outlook messages, ...
# This version is compatible with Python 2.6+ and 3.x
#
# Project website: http://www.decalage.info/olefile
#
# olefile is copyright (c) 2005-2015 Philippe Lagadec (http://www.decalage.info)
#
# olefile is based on the OleFileIO module from the PIL library v1.1.6
# See: http://www.pythonware.com/products/pil/index.htm
#
# The Python Imaging Library (PIL) is
# Copyright (c) 1997-2005 by Secret Labs AB
# Copyright (c) 1995-2005 by Fredrik Lundh
#
# See source code and LICENSE.txt for information on usage and redistribution.


# Since OleFileIO_PL v0.30, only Python 2.6+ and 3.x is supported
# This import enables print() as a function rather than a keyword
# (main requirement to be compatible with Python 3.x)
# The comment on the line below should be printed on Python 2.5 or older:
from __future__ import print_function   # This version of olefile requires Python 2.6+ or 3.x.


__author__  = "Philippe Lagadec"
__date__    = "2015-01-25"
__version__ = '0.42b'

#--- LICENSE ------------------------------------------------------------------

# olefile (formerly OleFileIO_PL) is copyright (c) 2005-2015 Philippe Lagadec
# (http://www.decalage.info)
#
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without modification,
# are permitted provided that the following conditions are met:
#
#  * Redistributions of source code must retain the above copyright notice, this
#    list of conditions and the following disclaimer.
#  * Redistributions in binary form must reproduce the above copyright notice,
#    this list of conditions and the following disclaimer in the documentation
#    and/or other materials provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

# ----------
# PIL License:
#
# olefile is based on source code from the OleFileIO module of the Python
# Imaging Library (PIL) published by Fredrik Lundh under the following license:

# The Python Imaging Library (PIL) is
#    Copyright (c) 1997-2005 by Secret Labs AB
#    Copyright (c) 1995-2005 by Fredrik Lundh
#
# By obtaining, using, and/or copying this software and/or its associated
# documentation, you agree that you have read, understood, and will comply with
# the following terms and conditions:
#
# Permission to use, copy, modify, and distribute this software and its
# associated documentation for any purpose and without fee is hereby granted,
# provided that the above copyright notice appears in all copies, and that both
# that copyright notice and this permission notice appear in supporting
# documentation, and that the name of Secret Labs AB or the author(s) not be used
# in advertising or publicity pertaining to distribution of the software
# without specific, written prior permission.
#
# SECRET LABS AB AND THE AUTHORS DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS
# SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS.
# IN NO EVENT SHALL SECRET LABS AB OR THE AUTHORS BE LIABLE FOR ANY SPECIAL,
# INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
# LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
# OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
# PERFORMANCE OF THIS SOFTWARE.

#-----------------------------------------------------------------------------
# CHANGELOG: (only olefile/OleFileIO_PL changes compared to PIL 1.1.6)
# 2005-05-11 v0.10 PL: - a few fixes for Python 2.4 compatibility
#                        (all changes flagged with [PL])
# 2006-02-22 v0.11 PL: - a few fixes for some Office 2003 documents which raise
#                        exceptions in _OleStream.__init__()
# 2006-06-09 v0.12 PL: - fixes for files above 6.8MB (DIFAT in loadfat)
#                      - added some constants
#                      - added header values checks
#                      - added some docstrings
#                      - getsect: bugfix in case sectors >512 bytes
#                      - getsect: added conformity checks
#                      - DEBUG_MODE constant to activate debug display
# 2007-09-04 v0.13 PL: - improved/translated (lots of) comments
#                      - updated license
#                      - converted tabs to 4 spaces
# 2007-11-19 v0.14 PL: - added OleFileIO._raise_defect() to adapt sensitivity
#                      - improved _unicode() to use Python 2.x unicode support
#                      - fixed bug in _OleDirectoryEntry
# 2007-11-25 v0.15 PL: - added safety checks to detect FAT loops
#                      - fixed _OleStream which didn't check stream size
#                      - added/improved many docstrings and comments
#                      - moved helper functions _unicode and _clsid out of
#                        OleFileIO class
#                      - improved OleFileIO._find() to add Unix path syntax
#                      - OleFileIO._find() is now case-insensitive
#                      - added get_type() and get_rootentry_name()
#                      - rewritten loaddirectory and _OleDirectoryEntry
# 2007-11-27 v0.16 PL: - added _OleDirectoryEntry.kids_dict
#                      - added detection of duplicate filenames in storages
#                      - added detection of duplicate references to streams
#                      - added get_size() and exists() to _OleDirectoryEntry
#                      - added isOleFile to check header before parsing
#                      - added __all__ list to control public keywords in pydoc
# 2007-12-04 v0.17 PL: - added _load_direntry to fix a bug in loaddirectory
#                      - improved _unicode(), added workarounds for Python <2.3
#                      - added set_debug_mode and -d option to set debug mode
#                      - fixed bugs in OleFileIO.open and _OleDirectoryEntry
#                      - added safety check in main for large or binary
#                        properties
#                      - allow size>0 for storages for some implementations
# 2007-12-05 v0.18 PL: - fixed several bugs in handling of FAT, MiniFAT and
#                        streams
#                      - added option '-c' in main to check all streams
# 2009-12-10 v0.19 PL: - bugfix for 32 bit arrays on 64 bits platforms
#                        (thanks to Ben G. and Martijn for reporting the bug)
# 2009-12-11 v0.20 PL: - bugfix in OleFileIO.open when filename is not plain str
# 2010-01-22 v0.21 PL: - added support for big-endian CPUs such as PowerPC Macs
# 2012-02-16 v0.22 PL: - fixed bug in getproperties, patch by chuckleberryfinn
#                        (https://bitbucket.org/decalage/olefileio_pl/issue/7)
#                      - added close method to OleFileIO (fixed issue #2)
# 2012-07-25 v0.23 PL: - added support for file-like objects (patch by mete0r_kr)
# 2013-05-05 v0.24 PL: - getproperties: added conversion from filetime to python
#                        datetime
#                      - main: displays properties with date format
#                      - new class OleMetadata to parse standard properties
#                      - added get_metadata method
# 2013-05-07 v0.24 PL: - a few improvements in OleMetadata
# 2013-05-24 v0.25 PL: - getproperties: option to not convert some timestamps
#                      - OleMetaData: total_edit_time is now a number of seconds,
#                        not a timestamp
#                      - getproperties: added support for VT_BOOL, VT_INT, V_UINT
#                      - getproperties: filter out null chars from strings
#                      - getproperties: raise non-fatal defects instead of
#                        exceptions when properties cannot be parsed properly
# 2013-05-27       PL: - getproperties: improved exception handling
#                      - _raise_defect: added option to set exception type
#                      - all non-fatal issues are now recorded, and displayed
#                        when run as a script
# 2013-07-11 v0.26 PL: - added methods to get modification and creation times
#                        of a directory entry or a storage/stream
#                      - fixed parsing of direntry timestamps
# 2013-07-24       PL: - new options in listdir to list storages and/or streams
# 2014-02-04 v0.30 PL: - upgraded code to support Python 3.x by Martin Panter
#                      - several fixes for Python 2.6 (xrange, MAGIC)
#                      - reused i32 from Pillow's _binary
# 2014-07-18 v0.31     - preliminary support for 4K sectors
# 2014-07-27 v0.31 PL: - a few improvements in OleFileIO.open (header parsing)
#                      - Fixed loadfat for large files with 4K sectors (issue #3)
# 2014-07-30 v0.32 PL: - added write_sect to write sectors to disk
#                      - added write_mode option to OleFileIO.__init__ and open
# 2014-07-31       PL: - fixed padding in write_sect for Python 3, added checks
#                      - added write_stream to write a stream to disk
# 2014-09-26 v0.40 PL: - renamed OleFileIO_PL to olefile
# 2014-11-09       NE: - added support for Jython (Niko Ehrenfeuchter)
# 2014-11-13 v0.41 PL: - improved isOleFile and OleFileIO.open to support OLE
#                        data in a string buffer and file-like objects.
# 2014-11-21       PL: - updated comments according to Pillow's commits
# 2015-01-24 v0.42 PL: - changed the default path name encoding from Latin-1
#                        to UTF-8 on Python 2.x (Unicode on Python 3.x)
#                      - added path_encoding option to override the default
#                      - fixed a bug in _list when a storage is empty

#-----------------------------------------------------------------------------
# TODO (for version 1.0):
# + get rid of print statements, to simplify Python 2.x and 3.x support
# + add is_stream and is_storage
# + remove leading and trailing slashes where a path is used
# + add functions path_list2str and path_str2list
# + fix how all the methods handle unicode str and/or bytes as arguments
# + add path attrib to _OleDirEntry, set it once and for all in init or
#   append_kids (then listdir/_list can be simplified)
# - TESTS with Linux, MacOSX, Python 1.5.2, various files, PIL, ...
# - add underscore to each private method, to avoid their display in
#   pydoc/epydoc documentation - Remove it for classes to be documented
# - replace all raised exceptions with _raise_defect (at least in OleFileIO)
# - merge code from _OleStream and OleFileIO.getsect to read sectors
#   (maybe add a class for FAT and MiniFAT ?)
# - add method to check all streams (follow sectors chains without storing all
#   stream in memory, and report anomalies)
# - use _OleDirectoryEntry.kids_dict to improve _find and _list ?
# - fix Unicode names handling (find some way to stay compatible with Py1.5.2)
#   => if possible avoid converting names to Latin-1
# - review DIFAT code: fix handling of DIFSECT blocks in FAT (not stop)
# - rewrite OleFileIO.getproperties
# - improve docstrings to show more sample uses
# - see also original notes and FIXME below
# - remove all obsolete FIXMEs
# - OleMetadata: fix version attrib according to
#   http://msdn.microsoft.com/en-us/library/dd945671%28v=office.12%29.aspx

# IDEAS:
# - in OleFileIO._open and _OleStream, use size=None instead of 0x7FFFFFFF for
#   streams with unknown size
# - use arrays of int instead of long integers for FAT/MiniFAT, to improve
#   performance and reduce memory usage ? (possible issue with values >2^31)
# - provide tests with unittest (may need write support to create samples)
# - move all debug code (and maybe dump methods) to a separate module, with
#   a class which inherits OleFileIO ?
# - fix docstrings to follow epydoc format
# - add support for big endian byte order ?
# - create a simple OLE explorer with wxPython

# FUTURE EVOLUTIONS to add write support:
# see issue #6 on Bitbucket:
# https://bitbucket.org/decalage/olefileio_pl/issue/6/improve-olefileio_pl-to-write-ole-files

#-----------------------------------------------------------------------------
# NOTES from PIL 1.1.6:

# History:
# 1997-01-20 fl   Created
# 1997-01-22 fl   Fixed 64-bit portability quirk
# 2003-09-09 fl   Fixed typo in OleFileIO.loadfat (noted by Daniel Haertle)
# 2004-02-29 fl   Changed long hex constants to signed integers
#
# Notes:
# FIXME: sort out sign problem (eliminate long hex constants)
# FIXME: change filename to use "a/b/c" instead of ["a", "b", "c"]
# FIXME: provide a glob mechanism function (using fnmatchcase)
#
# Literature:
#
# "FlashPix Format Specification, Appendix A", Kodak and Microsoft,
#  September 1996.
#
# Quotes:
#
# "If this document and functionality of the Software conflict,
#  the actual functionality of the Software represents the correct
#  functionality" -- Microsoft, in the OLE format specification

#------------------------------------------------------------------------------


import io
import sys
import struct
import array
import os.path
import datetime

#=== COMPATIBILITY WORKAROUNDS ================================================

# [PL] Define explicitly the public API to avoid private objects in pydoc:
#TODO: add more
# __all__ = ['OleFileIO', 'isOleFile', 'MAGIC']

# For Python 3.x, need to redefine long as int:
if str is not bytes:
    long = int

# Need to make sure we use xrange both on Python 2 and 3.x:
try:
    # on Python 2 we need xrange:
    iterrange = xrange
except:
    # no xrange, for Python 3 it was renamed as range:
    iterrange = range

# [PL] workaround to fix an issue with array item size on 64 bits systems:
if array.array('L').itemsize == 4:
    # on 32 bits platforms, long integers in an array are 32 bits:
    UINT32 = 'L'
elif array.array('I').itemsize == 4:
    # on 64 bits platforms, integers in an array are 32 bits:
    UINT32 = 'I'
elif array.array('i').itemsize == 4:
    # On 64 bit Jython, signed integers ('i') are the only way to store our 32
    # bit values in an array in a *somewhat* reasonable way, as the otherwise
    # perfectly suited 'H' (unsigned int, 32 bits) results in a completely
    # unusable behaviour. This is most likely caused by the fact that Java
    # doesn't have unsigned values, and thus Jython's "array" implementation,
    # which is based on "jarray", doesn't have them either.
    # NOTE: to trick Jython into converting the values it would normally
    # interpret as "signed" into "unsigned", a binary-and operation with
    # 0xFFFFFFFF can be used. This way it is possible to use the same comparing
    # operations on all platforms / implementations. The corresponding code
    # lines are flagged with a 'JYTHON-WORKAROUND' tag below.
    UINT32 = 'i'
else:
    raise ValueError('Need to fix a bug with 32 bit arrays, please contact author...')


# [PL] These workarounds were inspired from the Path module
# (see http://www.jorendorff.com/articles/python/path/)
try:
    basestring
except NameError:
    basestring = str

# [PL] Experimental setting: if True, OLE filenames will be kept in Unicode
# if False (default PIL behaviour), all filenames are converted to Latin-1.
KEEP_UNICODE_NAMES = True

if sys.version_info[0] < 3:
    # On Python 2.x, the default encoding for path names is UTF-8:
    DEFAULT_PATH_ENCODING = 'utf-8'
else:
    # On Python 3.x, the default encoding for path names is Unicode (None):
    DEFAULT_PATH_ENCODING = None


#=== DEBUGGING ===============================================================

#TODO: replace this by proper logging

# [PL] DEBUG display mode: False by default, use set_debug_mode() or "-d" on
# command line to change it.
DEBUG_MODE = False


[文档]def debug_print(msg): print(msg)
[文档]def debug_pass(msg): pass
debug = debug_pass
[文档]def set_debug_mode(debug_mode): """ Set debug mode on or off, to control display of debugging messages. :param mode: True or False """ global DEBUG_MODE, debug DEBUG_MODE = debug_mode if debug_mode: debug = debug_print else: debug = debug_pass
#=== CONSTANTS =============================================================== # magic bytes that should be at the beginning of every OLE file: MAGIC = b'\xD0\xCF\x11\xE0\xA1\xB1\x1A\xE1' # [PL]: added constants for Sector IDs (from AAF specifications) MAXREGSECT = 0xFFFFFFFA # (-6) maximum SECT DIFSECT = 0xFFFFFFFC # (-4) denotes a DIFAT sector in a FAT FATSECT = 0xFFFFFFFD # (-3) denotes a FAT sector in a FAT ENDOFCHAIN = 0xFFFFFFFE # (-2) end of a virtual stream chain FREESECT = 0xFFFFFFFF # (-1) unallocated sector # [PL]: added constants for Directory Entry IDs (from AAF specifications) MAXREGSID = 0xFFFFFFFA # (-6) maximum directory entry ID NOSTREAM = 0xFFFFFFFF # (-1) unallocated directory entry # [PL] object types in storage (from AAF specifications) STGTY_EMPTY = 0 # empty directory entry (according to OpenOffice.org doc) STGTY_STORAGE = 1 # element is a storage object STGTY_STREAM = 2 # element is a stream object STGTY_LOCKBYTES = 3 # element is an ILockBytes object STGTY_PROPERTY = 4 # element is an IPropertyStorage object STGTY_ROOT = 5 # element is a root storage # # -------------------------------------------------------------------- # property types VT_EMPTY = 0; VT_NULL = 1; VT_I2 = 2; VT_I4 = 3; VT_R4 = 4; VT_R8 = 5; VT_CY = 6; VT_DATE = 7; VT_BSTR = 8; VT_DISPATCH = 9; VT_ERROR = 10; VT_BOOL = 11; VT_VARIANT = 12; VT_UNKNOWN = 13; VT_DECIMAL = 14; VT_I1 = 16; VT_UI1 = 17; VT_UI2 = 18; VT_UI4 = 19; VT_I8 = 20; VT_UI8 = 21; VT_INT = 22; VT_UINT = 23; VT_VOID = 24; VT_HRESULT = 25; VT_PTR = 26; VT_SAFEARRAY = 27; VT_CARRAY = 28; VT_USERDEFINED = 29; VT_LPSTR = 30; VT_LPWSTR = 31; VT_FILETIME = 64; VT_BLOB = 65; VT_STREAM = 66; VT_STORAGE = 67; VT_STREAMED_OBJECT = 68; VT_STORED_OBJECT = 69; VT_BLOB_OBJECT = 70; VT_CF = 71; VT_CLSID = 72; VT_VECTOR = 0x1000; # map property id to name (for debugging purposes) VT = {} for keyword, var in list(vars().items()): if keyword[:3] == "VT_": VT[var] = keyword # # -------------------------------------------------------------------- # Some common document types (root.clsid fields) WORD_CLSID = "00020900-0000-0000-C000-000000000046" #TODO: check Excel, PPT, ... # [PL]: Defect levels to classify parsing errors - see OleFileIO._raise_defect() DEFECT_UNSURE = 10 # a case which looks weird, but not sure it's a defect DEFECT_POTENTIAL = 20 # a potential defect DEFECT_INCORRECT = 30 # an error according to specifications, but parsing # can go on DEFECT_FATAL = 40 # an error which cannot be ignored, parsing is # impossible # Minimal size of an empty OLE file, with 512-bytes sectors = 1536 bytes # (this is used in isOleFile and OleFile.open) MINIMAL_OLEFILE_SIZE = 1536 # [PL] add useful constants to __all__: # for key in list(vars().keys()): # if key.startswith('STGTY_') or key.startswith('DEFECT_'): # __all__.append(key) #=== FUNCTIONS ===============================================================
[文档]def isOleFile(filename): """ Test if a file is an OLE container (according to the magic bytes in its header). :param filename: string-like or file-like object, OLE file to parse - if filename is a string smaller than 1536 bytes, it is the path of the file to open. (bytes or unicode string) - if filename is a string longer than 1535 bytes, it is parsed as the content of an OLE file in memory. (bytes type only) - if filename is a file-like object (with read and seek methods), it is parsed as-is. :returns: True if OLE, False otherwise. """ # check if filename is a string-like or file-like object: if hasattr(filename, 'read'): # file-like object: use it directly header = filename.read(len(MAGIC)) # just in case, seek back to start of file: filename.seek(0) elif isinstance(filename, bytes) and len(filename) >= MINIMAL_OLEFILE_SIZE: # filename is a bytes string containing the OLE file to be parsed: header = filename[:len(MAGIC)] else: # string-like object: filename of file on disk header = open(filename, 'rb').read(len(MAGIC)) if header == MAGIC: return True else: return False
if bytes is str: # version for Python 2.x def i8(c): return ord(c) else: # version for Python 3.x
[文档] def i8(c): return c if c.__class__ is int else c[0]
#TODO: replace i16 and i32 with more readable struct.unpack equivalent?
[文档]def i16(c, o = 0): """ Converts a 2-bytes (16 bits) string to an integer. c: string containing bytes to convert o: offset of bytes to convert in string """ return struct.unpack("<H", c[o:o+2])[0]
[文档]def i32(c, o = 0): """ Converts a 4-bytes (32 bits) string to an integer. c: string containing bytes to convert o: offset of bytes to convert in string """ return struct.unpack("<I", c[o:o+4])[0]
def _clsid(clsid): """ Converts a CLSID to a human-readable string. :param clsid: string of length 16. """ assert len(clsid) == 16 # if clsid is only made of null bytes, return an empty string: # (PL: why not simply return the string with zeroes?) if not clsid.strip(b"\0"): return "" return (("%08X-%04X-%04X-%02X%02X-" + "%02X" * 6) % ((i32(clsid, 0), i16(clsid, 4), i16(clsid, 6)) + tuple(map(i8, clsid[8:16]))))
[文档]def filetime2datetime(filetime): """ convert FILETIME (64 bits int) to Python datetime.datetime """ # TODO: manage exception when microseconds is too large # inspired from http://code.activestate.com/recipes/511425-filetime-to-datetime/ _FILETIME_null_date = datetime.datetime(1601, 1, 1, 0, 0, 0) #debug('timedelta days=%d' % (filetime//(10*1000000*3600*24))) return _FILETIME_null_date + datetime.timedelta(microseconds=filetime//10)
#=== CLASSES ==================================================================
[文档]class OleMetadata(object): """ class to parse and store metadata from standard properties of OLE files. Available attributes: codepage, title, subject, author, keywords, comments, template, last_saved_by, revision_number, total_edit_time, last_printed, create_time, last_saved_time, num_pages, num_words, num_chars, thumbnail, creating_application, security, codepage_doc, category, presentation_target, bytes, lines, paragraphs, slides, notes, hidden_slides, mm_clips, scale_crop, heading_pairs, titles_of_parts, manager, company, links_dirty, chars_with_spaces, unused, shared_doc, link_base, hlinks, hlinks_changed, version, dig_sig, content_type, content_status, language, doc_version Note: an attribute is set to None when not present in the properties of the OLE file. References for SummaryInformation stream: - https://msdn.microsoft.com/en-us/library/dd942545.aspx - https://msdn.microsoft.com/en-us/library/dd925819%28v=office.12%29.aspx - https://msdn.microsoft.com/en-us/library/windows/desktop/aa380376%28v=vs.85%29.aspx - https://msdn.microsoft.com/en-us/library/aa372045.aspx - http://sedna-soft.de/articles/summary-information-stream/ - http://poi.apache.org/apidocs/org/apache/poi/hpsf/SummaryInformation.html References for DocumentSummaryInformation stream: - https://msdn.microsoft.com/en-us/library/dd945671%28v=office.12%29.aspx - https://msdn.microsoft.com/en-us/library/windows/desktop/aa380374%28v=vs.85%29.aspx - http://poi.apache.org/apidocs/org/apache/poi/hpsf/DocumentSummaryInformation.html new in version 0.25 """ # attribute names for SummaryInformation stream properties: # (ordered by property id, starting at 1) SUMMARY_ATTRIBS = ['codepage', 'title', 'subject', 'author', 'keywords', 'comments', 'template', 'last_saved_by', 'revision_number', 'total_edit_time', 'last_printed', 'create_time', 'last_saved_time', 'num_pages', 'num_words', 'num_chars', 'thumbnail', 'creating_application', 'security'] # attribute names for DocumentSummaryInformation stream properties: # (ordered by property id, starting at 1) DOCSUM_ATTRIBS = ['codepage_doc', 'category', 'presentation_target', 'bytes', 'lines', 'paragraphs', 'slides', 'notes', 'hidden_slides', 'mm_clips', 'scale_crop', 'heading_pairs', 'titles_of_parts', 'manager', 'company', 'links_dirty', 'chars_with_spaces', 'unused', 'shared_doc', 'link_base', 'hlinks', 'hlinks_changed', 'version', 'dig_sig', 'content_type', 'content_status', 'language', 'doc_version'] def __init__(self): """ Constructor for OleMetadata All attributes are set to None by default """ # properties from SummaryInformation stream self.codepage = None self.title = None self.subject = None self.author = None self.keywords = None self.comments = None self.template = None self.last_saved_by = None self.revision_number = None self.total_edit_time = None self.last_printed = None self.create_time = None self.last_saved_time = None self.num_pages = None self.num_words = None self.num_chars = None self.thumbnail = None self.creating_application = None self.security = None # properties from DocumentSummaryInformation stream self.codepage_doc = None self.category = None self.presentation_target = None self.bytes = None self.lines = None self.paragraphs = None self.slides = None self.notes = None self.hidden_slides = None self.mm_clips = None self.scale_crop = None self.heading_pairs = None self.titles_of_parts = None self.manager = None self.company = None self.links_dirty = None self.chars_with_spaces = None self.unused = None self.shared_doc = None self.link_base = None self.hlinks = None self.hlinks_changed = None self.version = None self.dig_sig = None self.content_type = None self.content_status = None self.language = None self.doc_version = None
[文档] def parse_properties(self, olefile): """ Parse standard properties of an OLE file, from the streams "\x05SummaryInformation" and "\x05DocumentSummaryInformation", if present. Properties are converted to strings, integers or python datetime objects. If a property is not present, its value is set to None. """ # first set all attributes to None: for attrib in (self.SUMMARY_ATTRIBS + self.DOCSUM_ATTRIBS): setattr(self, attrib, None) if olefile.exists("\x05SummaryInformation"): # get properties from the stream: # (converting timestamps to python datetime, except total_edit_time, # which is property #10) props = olefile.getproperties("\x05SummaryInformation", convert_time=True, no_conversion=[10]) # store them into this object's attributes: for i in range(len(self.SUMMARY_ATTRIBS)): # ids for standards properties start at 0x01, until 0x13 value = props.get(i+1, None) setattr(self, self.SUMMARY_ATTRIBS[i], value) if olefile.exists("\x05DocumentSummaryInformation"): # get properties from the stream: props = olefile.getproperties("\x05DocumentSummaryInformation", convert_time=True) # store them into this object's attributes: for i in range(len(self.DOCSUM_ATTRIBS)): # ids for standards properties start at 0x01, until 0x13 value = props.get(i+1, None) setattr(self, self.DOCSUM_ATTRIBS[i], value)
[文档] def dump(self): """ Dump all metadata, for debugging purposes. """ print('Properties from SummaryInformation stream:') for prop in self.SUMMARY_ATTRIBS: value = getattr(self, prop) print('- %s: %s' % (prop, repr(value))) print('Properties from DocumentSummaryInformation stream:') for prop in self.DOCSUM_ATTRIBS: value = getattr(self, prop) print('- %s: %s' % (prop, repr(value)))
#--- _OleStream --------------------------------------------------------------- class _OleStream(io.BytesIO): """ OLE2 Stream Returns a read-only file object which can be used to read the contents of a OLE stream (instance of the BytesIO class). To open a stream, use the openstream method in the OleFile class. This function can be used with either ordinary streams, or ministreams, depending on the offset, sectorsize, and fat table arguments. Attributes: - size: actual size of data stream, after it was opened. """ # FIXME: should store the list of sects obtained by following # the fat chain, and load new sectors on demand instead of # loading it all in one go. def __init__(self, fp, sect, size, offset, sectorsize, fat, filesize): """ Constructor for _OleStream class. :param fp: file object, the OLE container or the MiniFAT stream :param sect: sector index of first sector in the stream :param size: total size of the stream :param offset: offset in bytes for the first FAT or MiniFAT sector :param sectorsize: size of one sector :param fat: array/list of sector indexes (FAT or MiniFAT) :param filesize: size of OLE file (for debugging) :returns: a BytesIO instance containing the OLE stream """ debug('_OleStream.__init__:') debug(' sect=%d (%X), size=%d, offset=%d, sectorsize=%d, len(fat)=%d, fp=%s' % (sect, sect, size, offset, sectorsize, len(fat), repr(fp))) # [PL] To detect malformed documents with FAT loops, we compute the # expected number of sectors in the stream: unknown_size = False if size == 0x7FFFFFFF: # this is the case when called from OleFileIO._open(), and stream # size is not known in advance (for example when reading the # Directory stream). Then we can only guess maximum size: size = len(fat)*sectorsize # and we keep a record that size was unknown: unknown_size = True debug(' stream with UNKNOWN SIZE') nb_sectors = (size + (sectorsize-1)) // sectorsize debug('nb_sectors = %d' % nb_sectors) # This number should (at least) be less than the total number of # sectors in the given FAT: if nb_sectors > len(fat): raise IOError('malformed OLE document, stream too large') # optimization(?): data is first a list of strings, and join() is called # at the end to concatenate all in one string. # (this may not be really useful with recent Python versions) data = [] # if size is zero, then first sector index should be ENDOFCHAIN: if size == 0 and sect != ENDOFCHAIN: debug('size == 0 and sect != ENDOFCHAIN:') raise IOError('incorrect OLE sector index for empty stream') # [PL] A fixed-length for loop is used instead of an undefined while # loop to avoid DoS attacks: for i in range(nb_sectors): # Sector index may be ENDOFCHAIN, but only if size was unknown if sect == ENDOFCHAIN: if unknown_size: break else: # else this means that the stream is smaller than declared: debug('sect=ENDOFCHAIN before expected size') raise IOError('incomplete OLE stream') # sector index should be within FAT: if sect < 0 or sect >= len(fat): debug('sect=%d (%X) / len(fat)=%d' % (sect, sect, len(fat))) debug('i=%d / nb_sectors=%d' % (i, nb_sectors)) ## tmp_data = b"".join(data) ## f = open('test_debug.bin', 'wb') ## f.write(tmp_data) ## f.close() ## debug('data read so far: %d bytes' % len(tmp_data)) raise IOError('incorrect OLE FAT, sector index out of range') #TODO: merge this code with OleFileIO.getsect() ? #TODO: check if this works with 4K sectors: try: fp.seek(offset + sectorsize * sect) except: debug('sect=%d, seek=%d, filesize=%d' % (sect, offset+sectorsize*sect, filesize)) raise IOError('OLE sector index out of range') sector_data = fp.read(sectorsize) # [PL] check if there was enough data: # Note: if sector is the last of the file, sometimes it is not a # complete sector (of 512 or 4K), so we may read less than # sectorsize. if len(sector_data) != sectorsize and sect != (len(fat)-1): debug('sect=%d / len(fat)=%d, seek=%d / filesize=%d, len read=%d' % (sect, len(fat), offset+sectorsize*sect, filesize, len(sector_data))) debug('seek+len(read)=%d' % (offset+sectorsize*sect+len(sector_data))) raise IOError('incomplete OLE sector') data.append(sector_data) # jump to next sector in the FAT: try: sect = fat[sect] & 0xFFFFFFFF # JYTHON-WORKAROUND except IndexError: # [PL] if pointer is out of the FAT an exception is raised raise IOError('incorrect OLE FAT, sector index out of range') # [PL] Last sector should be a "end of chain" marker: if sect != ENDOFCHAIN: raise IOError('incorrect last sector index in OLE stream') data = b"".join(data) # Data is truncated to the actual stream size: if len(data) >= size: data = data[:size] # actual stream size is stored for future use: self.size = size elif unknown_size: # actual stream size was not known, now we know the size of read # data: self.size = len(data) else: # read data is less than expected: debug('len(data)=%d, size=%d' % (len(data), size)) raise IOError('OLE stream size is less than declared') # when all data is read in memory, BytesIO constructor is called io.BytesIO.__init__(self, data) # Then the _OleStream object can be used as a read-only file object. #--- _OleDirectoryEntry ------------------------------------------------------- class _OleDirectoryEntry(object): """ OLE2 Directory Entry """ # [PL] parsing code moved from OleFileIO.loaddirectory # struct to parse directory entries: # <: little-endian byte order, standard sizes # (note: this should guarantee that Q returns a 64 bits int) # 64s: string containing entry name in unicode (max 31 chars) + null char # H: uint16, number of bytes used in name buffer, including null = (len+1)*2 # B: uint8, dir entry type (between 0 and 5) # B: uint8, color: 0=black, 1=red # I: uint32, index of left child node in the red-black tree, NOSTREAM if none # I: uint32, index of right child node in the red-black tree, NOSTREAM if none # I: uint32, index of child root node if it is a storage, else NOSTREAM # 16s: CLSID, unique identifier (only used if it is a storage) # I: uint32, user flags # Q (was 8s): uint64, creation timestamp or zero # Q (was 8s): uint64, modification timestamp or zero # I: uint32, SID of first sector if stream or ministream, SID of 1st sector # of stream containing ministreams if root entry, 0 otherwise # I: uint32, total stream size in bytes if stream (low 32 bits), 0 otherwise # I: uint32, total stream size in bytes if stream (high 32 bits), 0 otherwise STRUCT_DIRENTRY = '<64sHBBIII16sIQQIII' # size of a directory entry: 128 bytes DIRENTRY_SIZE = 128 assert struct.calcsize(STRUCT_DIRENTRY) == DIRENTRY_SIZE def __init__(self, entry, sid, olefile): """ Constructor for an _OleDirectoryEntry object. Parses a 128-bytes entry from the OLE Directory stream. :param entry : string (must be 128 bytes long) :param sid : index of this directory entry in the OLE file directory :param olefile: OleFileIO containing this directory entry """ self.sid = sid # ref to olefile is stored for future use self.olefile = olefile # kids is a list of children entries, if this entry is a storage: # (list of _OleDirectoryEntry objects) self.kids = [] # kids_dict is a dictionary of children entries, indexed by their # name in lowercase: used to quickly find an entry, and to detect # duplicates self.kids_dict = {} # flag used to detect if the entry is referenced more than once in # directory: self.used = False # decode DirEntry ( name, namelength, self.entry_type, self.color, self.sid_left, self.sid_right, self.sid_child, clsid, self.dwUserFlags, self.createTime, self.modifyTime, self.isectStart, sizeLow, sizeHigh ) = struct.unpack(_OleDirectoryEntry.STRUCT_DIRENTRY, entry) if self.entry_type not in [STGTY_ROOT, STGTY_STORAGE, STGTY_STREAM, STGTY_EMPTY]: olefile.raise_defect(DEFECT_INCORRECT, 'unhandled OLE storage type') # only first directory entry can (and should) be root: if self.entry_type == STGTY_ROOT and sid != 0: olefile.raise_defect(DEFECT_INCORRECT, 'duplicate OLE root entry') if sid == 0 and self.entry_type != STGTY_ROOT: olefile.raise_defect(DEFECT_INCORRECT, 'incorrect OLE root entry') #debug (struct.unpack(fmt_entry, entry[:len_entry])) # name should be at most 31 unicode characters + null character, # so 64 bytes in total (31*2 + 2): if namelength > 64: olefile.raise_defect(DEFECT_INCORRECT, 'incorrect DirEntry name length') # if exception not raised, namelength is set to the maximum value: namelength = 64 # only characters without ending null char are kept: name = name[:(namelength-2)] #TODO: check if the name is actually followed by a null unicode character ([MS-CFB] 2.6.1) #TODO: check if the name does not contain forbidden characters: # [MS-CFB] 2.6.1: "The following characters are illegal and MUST NOT be part of the name: '/', '\', ':', '!'." # name is converted from UTF-16LE to the path encoding specified in the OleFileIO: self.name = olefile._decode_utf16_str(name) debug('DirEntry SID=%d: %s' % (self.sid, repr(self.name))) debug(' - type: %d' % self.entry_type) debug(' - sect: %d' % self.isectStart) debug(' - SID left: %d, right: %d, child: %d' % (self.sid_left, self.sid_right, self.sid_child)) # sizeHigh is only used for 4K sectors, it should be zero for 512 bytes # sectors, BUT apparently some implementations set it as 0xFFFFFFFF, 1 # or some other value so it cannot be raised as a defect in general: if olefile.sectorsize == 512: if sizeHigh != 0 and sizeHigh != 0xFFFFFFFF: debug('sectorsize=%d, sizeLow=%d, sizeHigh=%d (%X)' % (olefile.sectorsize, sizeLow, sizeHigh, sizeHigh)) olefile.raise_defect(DEFECT_UNSURE, 'incorrect OLE stream size') self.size = sizeLow else: self.size = sizeLow + (long(sizeHigh) << 32) debug(' - size: %d (sizeLow=%d, sizeHigh=%d)' % (self.size, sizeLow, sizeHigh)) self.clsid = _clsid(clsid) # a storage should have a null size, BUT some implementations such as # Word 8 for Mac seem to allow non-null values => Potential defect: if self.entry_type == STGTY_STORAGE and self.size != 0: olefile.raise_defect(DEFECT_POTENTIAL, 'OLE storage with size>0') # check if stream is not already referenced elsewhere: if self.entry_type in (STGTY_ROOT, STGTY_STREAM) and self.size > 0: if self.size < olefile.minisectorcutoff \ and self.entry_type == STGTY_STREAM: # only streams can be in MiniFAT # ministream object minifat = True else: minifat = False olefile._check_duplicate_stream(self.isectStart, minifat) def build_storage_tree(self): """ Read and build the red-black tree attached to this _OleDirectoryEntry object, if it is a storage. Note that this method builds a tree of all subentries, so it should only be called for the root object once. """ debug('build_storage_tree: SID=%d - %s - sid_child=%d' % (self.sid, repr(self.name), self.sid_child)) if self.sid_child != NOSTREAM: # if child SID is not NOSTREAM, then this entry is a storage. # Let's walk through the tree of children to fill the kids list: self.append_kids(self.sid_child) # Note from OpenOffice documentation: the safest way is to # recreate the tree because some implementations may store broken # red-black trees... # in the OLE file, entries are sorted on (length, name). # for convenience, we sort them on name instead: # (see rich comparison methods in this class) self.kids.sort() def append_kids(self, child_sid): """ Walk through red-black tree of children of this directory entry to add all of them to the kids list. (recursive method) :param child_sid : index of child directory entry to use, or None when called first time for the root. (only used during recursion) """ # [PL] this method was added to use simple recursion instead of a complex # algorithm. # if this is not a storage or a leaf of the tree, nothing to do: if child_sid == NOSTREAM: return # check if child SID is in the proper range: if child_sid < 0 or child_sid >= len(self.olefile.direntries): self.olefile.raise_defect(DEFECT_FATAL, 'OLE DirEntry index out of range') # get child direntry: child = self.olefile._load_direntry(child_sid) #direntries[child_sid] debug('append_kids: child_sid=%d - %s - sid_left=%d, sid_right=%d, sid_child=%d' % (child.sid, repr(child.name), child.sid_left, child.sid_right, child.sid_child)) # the directory entries are organized as a red-black tree. # (cf. Wikipedia for details) # First walk through left side of the tree: self.append_kids(child.sid_left) # Check if its name is not already used (case-insensitive): name_lower = child.name.lower() if name_lower in self.kids_dict: self.olefile.raise_defect(DEFECT_INCORRECT, "Duplicate filename in OLE storage") # Then the child_sid _OleDirectoryEntry object is appended to the # kids list and dictionary: self.kids.append(child) self.kids_dict[name_lower] = child # Check if kid was not already referenced in a storage: if child.used: self.olefile.raise_defect(DEFECT_INCORRECT, 'OLE Entry referenced more than once') child.used = True # Finally walk through right side of the tree: self.append_kids(child.sid_right) # Afterwards build kid's own tree if it's also a storage: child.build_storage_tree() def __eq__(self, other): "Compare entries by name" return self.name == other.name def __lt__(self, other): "Compare entries by name" return self.name < other.name def __ne__(self, other): return not self.__eq__(other) def __le__(self, other): return self.__eq__(other) or self.__lt__(other) # Reflected __lt__() and __le__() will be used for __gt__() and __ge__() #TODO: replace by the same function as MS implementation ? # (order by name length first, then case-insensitive order) def dump(self, tab = 0): "Dump this entry, and all its subentries (for debug purposes only)" TYPES = ["(invalid)", "(storage)", "(stream)", "(lockbytes)", "(property)", "(root)"] print(" "*tab + repr(self.name), TYPES[self.entry_type], end=' ') if self.entry_type in (STGTY_STREAM, STGTY_ROOT): print(self.size, "bytes", end=' ') print() if self.entry_type in (STGTY_STORAGE, STGTY_ROOT) and self.clsid: print(" "*tab + "{%s}" % self.clsid) for kid in self.kids: kid.dump(tab + 2) def getmtime(self): """ Return modification time of a directory entry. :returns: None if modification time is null, a python datetime object otherwise (UTC timezone) new in version 0.26 """ if self.modifyTime == 0: return None return filetime2datetime(self.modifyTime) def getctime(self): """ Return creation time of a directory entry. :returns: None if modification time is null, a python datetime object otherwise (UTC timezone) new in version 0.26 """ if self.createTime == 0: return None return filetime2datetime(self.createTime) #--- OleFileIO ----------------------------------------------------------------
[文档]class OleFileIO(object): """ OLE container object This class encapsulates the interface to an OLE 2 structured storage file. Use the :py:meth:`~PIL.OleFileIO.OleFileIO.listdir` and :py:meth:`~PIL.OleFileIO.OleFileIO.openstream` methods to access the contents of this file. Object names are given as a list of strings, one for each subentry level. The root entry should be omitted. For example, the following code extracts all image streams from a Microsoft Image Composer file:: ole = OleFileIO("fan.mic") for entry in ole.listdir(): if entry[1:2] == "Image": fin = ole.openstream(entry) fout = open(entry[0:1], "wb") while True: s = fin.read(8192) if not s: break fout.write(s) You can use the viewer application provided with the Python Imaging Library to view the resulting files (which happens to be standard TIFF files). """ def __init__(self, filename=None, raise_defects=DEFECT_FATAL, write_mode=False, debug=False, path_encoding=DEFAULT_PATH_ENCODING): """ Constructor for the OleFileIO class. :param filename: file to open. - if filename is a string smaller than 1536 bytes, it is the path of the file to open. (bytes or unicode string) - if filename is a string longer than 1535 bytes, it is parsed as the content of an OLE file in memory. (bytes type only) - if filename is a file-like object (with read, seek and tell methods), it is parsed as-is. :param raise_defects: minimal level for defects to be raised as exceptions. (use DEFECT_FATAL for a typical application, DEFECT_INCORRECT for a security-oriented application, see source code for details) :param write_mode: bool, if True the file is opened in read/write mode instead of read-only by default. :param debug: bool, set debug mode :param path_encoding: None or str, name of the codec to use for path names (streams and storages), or None for Unicode. Unicode by default on Python 3+, UTF-8 on Python 2.x. (new in olefile 0.42, was hardcoded to Latin-1 until olefile v0.41) """ set_debug_mode(debug) # minimal level for defects to be raised as exceptions: self._raise_defects_level = raise_defects # list of defects/issues not raised as exceptions: # tuples of (exception type, message) self.parsing_issues = [] self.write_mode = write_mode self.path_encoding = path_encoding self._filesize = None self.fp = None if filename: self.open(filename, write_mode=write_mode)
[文档] def raise_defect(self, defect_level, message, exception_type=IOError): """ This method should be called for any defect found during file parsing. It may raise an IOError exception according to the minimal level chosen for the OleFileIO object. :param defect_level: defect level, possible values are: - DEFECT_UNSURE : a case which looks weird, but not sure it's a defect - DEFECT_POTENTIAL : a potential defect - DEFECT_INCORRECT : an error according to specifications, but parsing can go on - DEFECT_FATAL : an error which cannot be ignored, parsing is impossible :param message: string describing the defect, used with raised exception. :param exception_type: exception class to be raised, IOError by default """ # added by [PL] if defect_level >= self._raise_defects_level: raise exception_type(message) else: # just record the issue, no exception raised: self.parsing_issues.append((exception_type, message))
def _decode_utf16_str(self, utf16_str, errors='replace'): """ Decode a string encoded in UTF-16 LE format, as found in the OLE directory or in property streams. Return a string encoded according to the path_encoding specified for the OleFileIO object. :param utf16_str: bytes string encoded in UTF-16 LE format :param errors: str, see python documentation for str.decode() :return: str, encoded according to path_encoding """ unicode_str = utf16_str.decode('UTF-16LE', errors) if self.path_encoding: # an encoding has been specified for path names: return unicode_str.encode(self.path_encoding, errors) else: # path_encoding=None, return the Unicode string as-is: return unicode_str
[文档] def open(self, filename, write_mode=False): """ Open an OLE2 file in read-only or read/write mode. Read and parse the header, FAT and directory. :param filename: string-like or file-like object, OLE file to parse - if filename is a string smaller than 1536 bytes, it is the path of the file to open. (bytes or unicode string) - if filename is a string longer than 1535 bytes, it is parsed as the content of an OLE file in memory. (bytes type only) - if filename is a file-like object (with read, seek and tell methods), it is parsed as-is. :param write_mode: bool, if True the file is opened in read/write mode instead of read-only by default. (ignored if filename is not a path) """ self.write_mode = write_mode # [PL] check if filename is a string-like or file-like object: # (it is better to check for a read() method) if hasattr(filename, 'read'): #TODO: also check seek and tell methods? # file-like object: use it directly self.fp = filename elif isinstance(filename, bytes) and len(filename) >= MINIMAL_OLEFILE_SIZE: # filename is a bytes string containing the OLE file to be parsed: # convert it to BytesIO self.fp = io.BytesIO(filename) else: # string-like object: filename of file on disk if self.write_mode: # open file in mode 'read with update, binary' # According to https://docs.python.org/2/library/functions.html#open # 'w' would truncate the file, 'a' may only append on some Unixes mode = 'r+b' else: # read-only mode by default mode = 'rb' self.fp = open(filename, mode) # obtain the filesize by using seek and tell, which should work on most # file-like objects: #TODO: do it above, using getsize with filename when possible? #TODO: fix code to fail with clear exception when filesize cannot be obtained filesize = 0 self.fp.seek(0, os.SEEK_END) try: filesize = self.fp.tell() finally: self.fp.seek(0) self._filesize = filesize # lists of streams in FAT and MiniFAT, to detect duplicate references # (list of indexes of first sectors of each stream) self._used_streams_fat = [] self._used_streams_minifat = [] header = self.fp.read(512) if len(header) != 512 or header[:8] != MAGIC: self.raise_defect(DEFECT_FATAL, "not an OLE2 structured storage file") # [PL] header structure according to AAF specifications: ##Header ##struct StructuredStorageHeader { // [offset from start (bytes), length (bytes)] ##BYTE _abSig[8]; // [00H,08] {0xd0, 0xcf, 0x11, 0xe0, 0xa1, 0xb1, ## // 0x1a, 0xe1} for current version ##CLSID _clsid; // [08H,16] reserved must be zero (WriteClassStg/ ## // GetClassFile uses root directory class id) ##USHORT _uMinorVersion; // [18H,02] minor version of the format: 33 is ## // written by reference implementation ##USHORT _uDllVersion; // [1AH,02] major version of the dll/format: 3 for ## // 512-byte sectors, 4 for 4 KB sectors ##USHORT _uByteOrder; // [1CH,02] 0xFFFE: indicates Intel byte-ordering ##USHORT _uSectorShift; // [1EH,02] size of sectors in power-of-two; ## // typically 9 indicating 512-byte sectors ##USHORT _uMiniSectorShift; // [20H,02] size of mini-sectors in power-of-two; ## // typically 6 indicating 64-byte mini-sectors ##USHORT _usReserved; // [22H,02] reserved, must be zero ##ULONG _ulReserved1; // [24H,04] reserved, must be zero ##FSINDEX _csectDir; // [28H,04] must be zero for 512-byte sectors, ## // number of SECTs in directory chain for 4 KB ## // sectors ##FSINDEX _csectFat; // [2CH,04] number of SECTs in the FAT chain ##SECT _sectDirStart; // [30H,04] first SECT in the directory chain ##DFSIGNATURE _signature; // [34H,04] signature used for transactions; must ## // be zero. The reference implementation ## // does not support transactions ##ULONG _ulMiniSectorCutoff; // [38H,04] maximum size for a mini stream; ## // typically 4096 bytes ##SECT _sectMiniFatStart; // [3CH,04] first SECT in the MiniFAT chain ##FSINDEX _csectMiniFat; // [40H,04] number of SECTs in the MiniFAT chain ##SECT _sectDifStart; // [44H,04] first SECT in the DIFAT chain ##FSINDEX _csectDif; // [48H,04] number of SECTs in the DIFAT chain ##SECT _sectFat[109]; // [4CH,436] the SECTs of first 109 FAT sectors ##}; # [PL] header decoding: # '<' indicates little-endian byte ordering for Intel (cf. struct module help) fmt_header = '<8s16sHHHHHHLLLLLLLLLL' header_size = struct.calcsize(fmt_header) debug("fmt_header size = %d, +FAT = %d" % (header_size, header_size + 109*4)) header1 = header[:header_size] ( self.Sig, self.clsid, self.MinorVersion, self.DllVersion, self.ByteOrder, self.SectorShift, self.MiniSectorShift, self.Reserved, self.Reserved1, self.csectDir, self.csectFat, self.sectDirStart, self.signature, self.MiniSectorCutoff, self.MiniFatStart, self.csectMiniFat, self.sectDifStart, self.csectDif ) = struct.unpack(fmt_header, header1) debug(struct.unpack(fmt_header, header1)) if self.Sig != MAGIC: # OLE signature should always be present self.raise_defect(DEFECT_FATAL, "incorrect OLE signature") if self.clsid != bytearray(16): # according to AAF specs, CLSID should always be zero self.raise_defect(DEFECT_INCORRECT, "incorrect CLSID in OLE header") debug("MinorVersion = %d" % self.MinorVersion) debug("DllVersion = %d" % self.DllVersion) if self.DllVersion not in [3, 4]: # version 3: usual format, 512 bytes per sector # version 4: large format, 4K per sector self.raise_defect(DEFECT_INCORRECT, "incorrect DllVersion in OLE header") debug("ByteOrder = %X" % self.ByteOrder) if self.ByteOrder != 0xFFFE: # For now only common little-endian documents are handled correctly self.raise_defect(DEFECT_FATAL, "incorrect ByteOrder in OLE header") # TODO: add big-endian support for documents created on Mac ? # But according to [MS-CFB] ? v20140502, ByteOrder MUST be 0xFFFE. self.SectorSize = 2**self.SectorShift debug("SectorSize = %d" % self.SectorSize) if self.SectorSize not in [512, 4096]: self.raise_defect(DEFECT_INCORRECT, "incorrect SectorSize in OLE header") if (self.DllVersion == 3 and self.SectorSize != 512) \ or (self.DllVersion == 4 and self.SectorSize != 4096): self.raise_defect(DEFECT_INCORRECT, "SectorSize does not match DllVersion in OLE header") self.MiniSectorSize = 2**self.MiniSectorShift debug("MiniSectorSize = %d" % self.MiniSectorSize) if self.MiniSectorSize not in [64]: self.raise_defect(DEFECT_INCORRECT, "incorrect MiniSectorSize in OLE header") if self.Reserved != 0 or self.Reserved1 != 0: self.raise_defect(DEFECT_INCORRECT, "incorrect OLE header (non-null reserved bytes)") debug("csectDir = %d" % self.csectDir) # Number of directory sectors (only allowed if DllVersion != 3) if self.SectorSize == 512 and self.csectDir != 0: self.raise_defect(DEFECT_INCORRECT, "incorrect csectDir in OLE header") debug("csectFat = %d" % self.csectFat) # csectFat = number of FAT sectors in the file debug("sectDirStart = %X" % self.sectDirStart) # sectDirStart = 1st sector containing the directory debug("signature = %d" % self.signature) # Signature should be zero, BUT some implementations do not follow this # rule => only a potential defect: # (according to MS-CFB, may be != 0 for applications supporting file # transactions) if self.signature != 0: self.raise_defect(DEFECT_POTENTIAL, "incorrect OLE header (signature>0)") debug("MiniSectorCutoff = %d" % self.MiniSectorCutoff) # MS-CFB: This integer field MUST be set to 0x00001000. This field # specifies the maximum size of a user-defined data stream allocated # from the mini FAT and mini stream, and that cutoff is 4096 bytes. # Any user-defined data stream larger than or equal to this cutoff size # must be allocated as normal sectors from the FAT. if self.MiniSectorCutoff != 0x1000: self.raise_defect(DEFECT_INCORRECT, "incorrect MiniSectorCutoff in OLE header") debug("MiniFatStart = %X" % self.MiniFatStart) debug("csectMiniFat = %d" % self.csectMiniFat) debug("sectDifStart = %X" % self.sectDifStart) debug("csectDif = %d" % self.csectDif) # calculate the number of sectors in the file # (-1 because header doesn't count) self.nb_sect = ((filesize + self.SectorSize-1) // self.SectorSize) - 1 debug("Number of sectors in the file: %d" % self.nb_sect) #TODO: change this test, because an OLE file MAY contain other data # after the last sector. # file clsid self.clsid = _clsid(header[8:24]) #TODO: remove redundant attributes, and fix the code which uses them? self.sectorsize = self.SectorSize #1 << i16(header, 30) self.minisectorsize = self.MiniSectorSize #1 << i16(header, 32) self.minisectorcutoff = self.MiniSectorCutoff # i32(header, 56) # check known streams for duplicate references (these are always in FAT, # never in MiniFAT): self._check_duplicate_stream(self.sectDirStart) # check MiniFAT only if it is not empty: if self.csectMiniFat: self._check_duplicate_stream(self.MiniFatStart) # check DIFAT only if it is not empty: if self.csectDif: self._check_duplicate_stream(self.sectDifStart) # Load file allocation tables self.loadfat(header) # Load directory. This sets both the direntries list (ordered by sid) # and the root (ordered by hierarchy) members. self.loaddirectory(self.sectDirStart)#i32(header, 48)) self.ministream = None self.minifatsect = self.MiniFatStart #i32(header, 60)
[文档] def close(self): """ close the OLE file, to release the file object """ self.fp.close()
def _check_duplicate_stream(self, first_sect, minifat=False): """ Checks if a stream has not been already referenced elsewhere. This method should only be called once for each known stream, and only if stream size is not null. :param first_sect: int, index of first sector of the stream in FAT :param minifat: bool, if True, stream is located in the MiniFAT, else in the FAT """ if minifat: debug('_check_duplicate_stream: sect=%d in MiniFAT' % first_sect) used_streams = self._used_streams_minifat else: debug('_check_duplicate_stream: sect=%d in FAT' % first_sect) # some values can be safely ignored (not a real stream): if first_sect in (DIFSECT, FATSECT, ENDOFCHAIN, FREESECT): return used_streams = self._used_streams_fat #TODO: would it be more efficient using a dict or hash values, instead # of a list of long ? if first_sect in used_streams: self.raise_defect(DEFECT_INCORRECT, 'Stream referenced twice') else: used_streams.append(first_sect)
[文档] def dumpfat(self, fat, firstindex=0): "Displays a part of FAT in human-readable form for debugging purpose" # [PL] added only for debug if not DEBUG_MODE: return # dictionary to convert special FAT values in human-readable strings VPL = 8 # values per line (8+1 * 8+1 = 81) fatnames = { FREESECT: "..free..", ENDOFCHAIN: "[ END. ]", FATSECT: "FATSECT ", DIFSECT: "DIFSECT " } nbsect = len(fat) nlines = (nbsect+VPL-1)//VPL print("index", end=" ") for i in range(VPL): print("%8X" % i, end=" ") print() for l in range(nlines): index = l*VPL print("%8X:" % (firstindex+index), end=" ") for i in range(index, index+VPL): if i >= nbsect: break sect = fat[i] aux = sect & 0xFFFFFFFF # JYTHON-WORKAROUND if aux in fatnames: name = fatnames[aux] else: if sect == i+1: name = " --->" else: name = "%8X" % sect print(name, end=" ") print()
[文档] def dumpsect(self, sector, firstindex=0): "Displays a sector in a human-readable form, for debugging purpose." if not DEBUG_MODE: return VPL = 8 # number of values per line (8+1 * 8+1 = 81) tab = array.array(UINT32, sector) if sys.byteorder == 'big': tab.byteswap() nbsect = len(tab) nlines = (nbsect+VPL-1)//VPL print("index", end=" ") for i in range(VPL): print("%8X" % i, end=" ") print() for l in range(nlines): index = l*VPL print("%8X:" % (firstindex+index), end=" ") for i in range(index, index+VPL): if i >= nbsect: break sect = tab[i] name = "%8X" % sect print(name, end=" ") print()
[文档] def sect2array(self, sect): """ convert a sector to an array of 32 bits unsigned integers, swapping bytes on big endian CPUs such as PowerPC (old Macs) """ a = array.array(UINT32, sect) # if CPU is big endian, swap bytes: if sys.byteorder == 'big': a.byteswap() return a
[文档] def loadfat_sect(self, sect): """ Adds the indexes of the given sector to the FAT :param sect: string containing the first FAT sector, or array of long integers :returns: index of last FAT sector. """ # a FAT sector is an array of ulong integers. if isinstance(sect, array.array): # if sect is already an array it is directly used fat1 = sect else: # if it's a raw sector, it is parsed in an array fat1 = self.sect2array(sect) self.dumpsect(sect) # The FAT is a sector chain starting at the first index of itself. for isect in fat1: isect = isect & 0xFFFFFFFF # JYTHON-WORKAROUND debug("isect = %X" % isect) if isect == ENDOFCHAIN or isect == FREESECT: # the end of the sector chain has been reached debug("found end of sector chain") break # read the FAT sector s = self.getsect(isect) # parse it as an array of 32 bits integers, and add it to the # global FAT array nextfat = self.sect2array(s) self.fat = self.fat + nextfat return isect
[文档] def loadfat(self, header): """ Load the FAT table. """ # The 1st sector of the file contains sector numbers for the first 109 # FAT sectors, right after the header which is 76 bytes long. # (always 109, whatever the sector size: 512 bytes = 76+4*109) # Additional sectors are described by DIF blocks sect = header[76:512] debug("len(sect)=%d, so %d integers" % (len(sect), len(sect)//4)) #fat = [] # [PL] FAT is an array of 32 bits unsigned ints, it's more effective # to use an array than a list in Python. # It's initialized as empty first: self.fat = array.array(UINT32) self.loadfat_sect(sect) #self.dumpfat(self.fat) ## for i in range(0, len(sect), 4): ## ix = i32(sect, i) ## # [PL] if ix == -2 or ix == -1: # ix == 0xFFFFFFFE or ix == 0xFFFFFFFF: ## if ix == 0xFFFFFFFE or ix == 0xFFFFFFFF: ## break ## s = self.getsect(ix) ## #fat = fat + [i32(s, i) for i in range(0, len(s), 4)] ## fat = fat + array.array(UINT32, s) if self.csectDif != 0: # [PL] There's a DIFAT because file is larger than 6.8MB # some checks just in case: if self.csectFat <= 109: # there must be at least 109 blocks in header and the rest in # DIFAT, so number of sectors must be >109. self.raise_defect(DEFECT_INCORRECT, 'incorrect DIFAT, not enough sectors') if self.sectDifStart >= self.nb_sect: # initial DIFAT block index must be valid self.raise_defect(DEFECT_FATAL, 'incorrect DIFAT, first index out of range') debug("DIFAT analysis...") # We compute the necessary number of DIFAT sectors : # Number of pointers per DIFAT sector = (sectorsize/4)-1 # (-1 because the last pointer is the next DIFAT sector number) nb_difat_sectors = (self.sectorsize//4)-1 # (if 512 bytes: each DIFAT sector = 127 pointers + 1 towards next DIFAT sector) nb_difat = (self.csectFat-109 + nb_difat_sectors-1)//nb_difat_sectors debug("nb_difat = %d" % nb_difat) if self.csectDif != nb_difat: raise IOError('incorrect DIFAT') isect_difat = self.sectDifStart for i in iterrange(nb_difat): debug("DIFAT block %d, sector %X" % (i, isect_difat)) #TODO: check if corresponding FAT SID = DIFSECT sector_difat = self.getsect(isect_difat) difat = self.sect2array(sector_difat) self.dumpsect(sector_difat) self.loadfat_sect(difat[:nb_difat_sectors]) # last DIFAT pointer is next DIFAT sector: isect_difat = difat[nb_difat_sectors] debug("next DIFAT sector: %X" % isect_difat) # checks: if isect_difat not in [ENDOFCHAIN, FREESECT]: # last DIFAT pointer value must be ENDOFCHAIN or FREESECT raise IOError('incorrect end of DIFAT') ## if len(self.fat) != self.csectFat: ## # FAT should contain csectFat blocks ## print("FAT length: %d instead of %d" % (len(self.fat), self.csectFat)) ## raise IOError('incorrect DIFAT') # since FAT is read from fixed-size sectors, it may contain more values # than the actual number of sectors in the file. # Keep only the relevant sector indexes: if len(self.fat) > self.nb_sect: debug('len(fat)=%d, shrunk to nb_sect=%d' % (len(self.fat), self.nb_sect)) self.fat = self.fat[:self.nb_sect] debug('\nFAT:') self.dumpfat(self.fat)
[文档] def loadminifat(self): """ Load the MiniFAT table. """ # MiniFAT is stored in a standard sub-stream, pointed to by a header # field. # NOTE: there are two sizes to take into account for this stream: # 1) Stream size is calculated according to the number of sectors # declared in the OLE header. This allocated stream may be more than # needed to store the actual sector indexes. # (self.csectMiniFat is the number of sectors of size self.SectorSize) stream_size = self.csectMiniFat * self.SectorSize # 2) Actually used size is calculated by dividing the MiniStream size # (given by root entry size) by the size of mini sectors, *4 for # 32 bits indexes: nb_minisectors = (self.root.size + self.MiniSectorSize-1) // self.MiniSectorSize used_size = nb_minisectors * 4 debug('loadminifat(): minifatsect=%d, nb FAT sectors=%d, used_size=%d, stream_size=%d, nb MiniSectors=%d' % (self.minifatsect, self.csectMiniFat, used_size, stream_size, nb_minisectors)) if used_size > stream_size: # This is not really a problem, but may indicate a wrong implementation: self.raise_defect(DEFECT_INCORRECT, 'OLE MiniStream is larger than MiniFAT') # In any case, first read stream_size: s = self._open(self.minifatsect, stream_size, force_FAT=True).read() # [PL] Old code replaced by an array: # self.minifat = [i32(s, i) for i in range(0, len(s), 4)] self.minifat = self.sect2array(s) # Then shrink the array to used size, to avoid indexes out of MiniStream: debug('MiniFAT shrunk from %d to %d sectors' % (len(self.minifat), nb_minisectors)) self.minifat = self.minifat[:nb_minisectors] debug('loadminifat(): len=%d' % len(self.minifat)) debug('\nMiniFAT:') self.dumpfat(self.minifat)
[文档] def getsect(self, sect): """ Read given sector from file on disk. :param sect: int, sector index :returns: a string containing the sector data. """ # From [MS-CFB]: A sector number can be converted into a byte offset # into the file by using the following formula: # (sector number + 1) x Sector Size. # This implies that sector #0 of the file begins at byte offset Sector # Size, not at 0. # [PL] the original code in PIL was wrong when sectors are 4KB instead of # 512 bytes: # self.fp.seek(512 + self.sectorsize * sect) # [PL]: added safety checks: # print("getsect(%X)" % sect) try: self.fp.seek(self.sectorsize * (sect+1)) except: debug('getsect(): sect=%X, seek=%d, filesize=%d' % (sect, self.sectorsize*(sect+1), self._filesize)) self.raise_defect(DEFECT_FATAL, 'OLE sector index out of range') sector = self.fp.read(self.sectorsize) if len(sector) != self.sectorsize: debug('getsect(): sect=%X, read=%d, sectorsize=%d' % (sect, len(sector), self.sectorsize)) self.raise_defect(DEFECT_FATAL, 'incomplete OLE sector') return sector
[文档] def write_sect(self, sect, data, padding=b'\x00'): """ Write given sector to file on disk. :param sect: int, sector index :param data: bytes, sector data :param padding: single byte, padding character if data < sector size """ if not isinstance(data, bytes): raise TypeError("write_sect: data must be a bytes string") if not isinstance(padding, bytes) or len(padding) != 1: raise TypeError("write_sect: padding must be a bytes string of 1 char") #TODO: we could allow padding=None for no padding at all try: self.fp.seek(self.sectorsize * (sect+1)) except: debug('write_sect(): sect=%X, seek=%d, filesize=%d' % (sect, self.sectorsize*(sect+1), self._filesize)) self.raise_defect(DEFECT_FATAL, 'OLE sector index out of range') if len(data) < self.sectorsize: # add padding data += padding * (self.sectorsize - len(data)) elif len(data) < self.sectorsize: raise ValueError("Data is larger than sector size") self.fp.write(data)
[文档] def loaddirectory(self, sect): """ Load the directory. :param sect: sector index of directory stream. """ # The directory is stored in a standard # substream, independent of its size. # open directory stream as a read-only file: # (stream size is not known in advance) self.directory_fp = self._open(sect) # [PL] to detect malformed documents and avoid DoS attacks, the maximum # number of directory entries can be calculated: max_entries = self.directory_fp.size // 128 debug('loaddirectory: size=%d, max_entries=%d' % (self.directory_fp.size, max_entries)) # Create list of directory entries # self.direntries = [] # We start with a list of "None" object self.direntries = [None] * max_entries ## for sid in iterrange(max_entries): ## entry = fp.read(128) ## if not entry: ## break ## self.direntries.append(_OleDirectoryEntry(entry, sid, self)) # load root entry: root_entry = self._load_direntry(0) # Root entry is the first entry: self.root = self.direntries[0] # read and build all storage trees, starting from the root: self.root.build_storage_tree()
def _load_direntry(self, sid): """ Load a directory entry from the directory. This method should only be called once for each storage/stream when loading the directory. :param sid: index of storage/stream in the directory. :returns: a _OleDirectoryEntry object :exception IOError: if the entry has always been referenced. """ # check if SID is OK: if sid < 0 or sid >= len(self.direntries): self.raise_defect(DEFECT_FATAL, "OLE directory index out of range") # check if entry was already referenced: if self.direntries[sid] is not None: self.raise_defect(DEFECT_INCORRECT, "double reference for OLE stream/storage") # if exception not raised, return the object return self.direntries[sid] self.directory_fp.seek(sid * 128) entry = self.directory_fp.read(128) self.direntries[sid] = _OleDirectoryEntry(entry, sid, self) return self.direntries[sid]
[文档] def dumpdirectory(self): """ Dump directory (for debugging only) """ self.root.dump()
def _open(self, start, size = 0x7FFFFFFF, force_FAT=False): """ Open a stream, either in FAT or MiniFAT according to its size. (openstream helper) :param start: index of first sector :param size: size of stream (or nothing if size is unknown) :param force_FAT: if False (default), stream will be opened in FAT or MiniFAT according to size. If True, it will always be opened in FAT. """ debug('OleFileIO.open(): sect=%d, size=%d, force_FAT=%s' % (start, size, str(force_FAT))) # stream size is compared to the MiniSectorCutoff threshold: if size < self.minisectorcutoff and not force_FAT: # ministream object if not self.ministream: # load MiniFAT if it wasn't already done: self.loadminifat() # The first sector index of the miniFAT stream is stored in the # root directory entry: size_ministream = self.root.size debug('Opening MiniStream: sect=%d, size=%d' % (self.root.isectStart, size_ministream)) self.ministream = self._open(self.root.isectStart, size_ministream, force_FAT=True) return _OleStream(fp=self.ministream, sect=start, size=size, offset=0, sectorsize=self.minisectorsize, fat=self.minifat, filesize=self.ministream.size) else: # standard stream return _OleStream(fp=self.fp, sect=start, size=size, offset=self.sectorsize, sectorsize=self.sectorsize, fat=self.fat, filesize=self._filesize) def _list(self, files, prefix, node, streams=True, storages=False): """ listdir helper :param files: list of files to fill in :param prefix: current location in storage tree (list of names) :param node: current node (_OleDirectoryEntry object) :param streams: bool, include streams if True (True by default) - new in v0.26 :param storages: bool, include storages if True (False by default) - new in v0.26 (note: the root storage is never included) """ prefix = prefix + [node.name] for entry in node.kids: if entry.entry_type == STGTY_STORAGE: # this is a storage if storages: # add it to the list files.append(prefix[1:] + [entry.name]) # check its kids self._list(files, prefix, entry, streams, storages) elif entry.entry_type == STGTY_STREAM: # this is a stream if streams: # add it to the list files.append(prefix[1:] + [entry.name]) else: self.raise_defect(DEFECT_INCORRECT, 'The directory tree contains an entry which is not a stream nor a storage.')
[文档] def listdir(self, streams=True, storages=False): """ Return a list of streams and/or storages stored in this file :param streams: bool, include streams if True (True by default) - new in v0.26 :param storages: bool, include storages if True (False by default) - new in v0.26 (note: the root storage is never included) :returns: list of stream and/or storage paths """ files = [] self._list(files, [], self.root, streams, storages) return files
def _find(self, filename): """ Returns directory entry of given filename. (openstream helper) Note: this method is case-insensitive. :param filename: path of stream in storage tree (except root entry), either: - a string using Unix path syntax, for example: 'storage_1/storage_1.2/stream' - or a list of storage filenames, path to the desired stream/storage. Example: ['storage_1', 'storage_1.2', 'stream'] :returns: sid of requested filename :exception IOError: if file not found """ # if filename is a string instead of a list, split it on slashes to # convert to a list: if isinstance(filename, basestring): filename = filename.split('/') # walk across storage tree, following given path: node = self.root for name in filename: for kid in node.kids: if kid.name.lower() == name.lower(): break else: raise IOError("file not found") node = kid return node.sid
[文档] def openstream(self, filename): """ Open a stream as a read-only file object (BytesIO). Note: filename is case-insensitive. :param filename: path of stream in storage tree (except root entry), either: - a string using Unix path syntax, for example: 'storage_1/storage_1.2/stream' - or a list of storage filenames, path to the desired stream/storage. Example: ['storage_1', 'storage_1.2', 'stream'] :returns: file object (read-only) :exception IOError: if filename not found, or if this is not a stream. """ sid = self._find(filename) entry = self.direntries[sid] if entry.entry_type != STGTY_STREAM: raise IOError("this file is not a stream") return self._open(entry.isectStart, entry.size)
[文档] def write_stream(self, stream_name, data): """ Write a stream to disk. For now, it is only possible to replace an existing stream by data of the same size. :param stream_name: path of stream in storage tree (except root entry), either: - a string using Unix path syntax, for example: 'storage_1/storage_1.2/stream' - or a list of storage filenames, path to the desired stream/storage. Example: ['storage_1', 'storage_1.2', 'stream'] :param data: bytes, data to be written, must be the same size as the original stream. """ if not isinstance(data, bytes): raise TypeError("write_stream: data must be a bytes string") sid = self._find(stream_name) entry = self.direntries[sid] if entry.entry_type != STGTY_STREAM: raise IOError("this is not a stream") size = entry.size if size != len(data): raise ValueError("write_stream: data must be the same size as the existing stream") if size < self.minisectorcutoff: raise NotImplementedError("Writing a stream in MiniFAT is not implemented yet") sect = entry.isectStart # number of sectors to write nb_sectors = (size + (self.sectorsize-1)) // self.sectorsize debug('nb_sectors = %d' % nb_sectors) for i in range(nb_sectors): # try: # self.fp.seek(offset + self.sectorsize * sect) # except: # debug('sect=%d, seek=%d' % # (sect, offset+self.sectorsize*sect)) # raise IOError('OLE sector index out of range') # extract one sector from data, the last one being smaller: if i < (nb_sectors-1): data_sector = data[i*self.sectorsize:(i+1)*self.sectorsize] #TODO: comment this if it works assert(len(data_sector) == self.sectorsize) else: data_sector = data[i*self.sectorsize:] # TODO: comment this if it works debug('write_stream: size=%d sectorsize=%d data_sector=%d size%%sectorsize=%d' % (size, self.sectorsize, len(data_sector), size % self.sectorsize)) assert(len(data_sector) % self.sectorsize == size % self.sectorsize) self.write_sect(sect, data_sector) # self.fp.write(data_sector) # jump to next sector in the FAT: try: sect = self.fat[sect] except IndexError: # [PL] if pointer is out of the FAT an exception is raised raise IOError('incorrect OLE FAT, sector index out of range') # [PL] Last sector should be a "end of chain" marker: if sect != ENDOFCHAIN: raise IOError('incorrect last sector index in OLE stream')
[文档] def get_type(self, filename): """ Test if given filename exists as a stream or a storage in the OLE container, and return its type. :param filename: path of stream in storage tree. (see openstream for syntax) :returns: False if object does not exist, its entry type (>0) otherwise: - STGTY_STREAM: a stream - STGTY_STORAGE: a storage - STGTY_ROOT: the root entry """ try: sid = self._find(filename) entry = self.direntries[sid] return entry.entry_type except: return False
[文档] def getmtime(self, filename): """ Return modification time of a stream/storage. :param filename: path of stream/storage in storage tree. (see openstream for syntax) :returns: None if modification time is null, a python datetime object otherwise (UTC timezone) new in version 0.26 """ sid = self._find(filename) entry = self.direntries[sid] return entry.getmtime()
[文档] def getctime(self, filename): """ Return creation time of a stream/storage. :param filename: path of stream/storage in storage tree. (see openstream for syntax) :returns: None if creation time is null, a python datetime object otherwise (UTC timezone) new in version 0.26 """ sid = self._find(filename) entry = self.direntries[sid] return entry.getctime()
[文档] def exists(self, filename): """ Test if given filename exists as a stream or a storage in the OLE container. Note: filename is case-insensitive. :param filename: path of stream in storage tree. (see openstream for syntax) :returns: True if object exist, else False. """ try: sid = self._find(filename) return True except: return False
[文档] def get_size(self, filename): """ Return size of a stream in the OLE container, in bytes. :param filename: path of stream in storage tree (see openstream for syntax) :returns: size in bytes (long integer) :exception IOError: if file not found :exception TypeError: if this is not a stream. """ sid = self._find(filename) entry = self.direntries[sid] if entry.entry_type != STGTY_STREAM: #TODO: Should it return zero instead of raising an exception ? raise TypeError('object is not an OLE stream') return entry.size
[文档] def get_rootentry_name(self): """ Return root entry name. Should usually be 'Root Entry' or 'R' in most implementations. """ return self.root.name
[文档] def getproperties(self, filename, convert_time=False, no_conversion=None): """ Return properties described in substream. :param filename: path of stream in storage tree (see openstream for syntax) :param convert_time: bool, if True timestamps will be converted to Python datetime :param no_conversion: None or list of int, timestamps not to be converted (for example total editing time is not a real timestamp) :returns: a dictionary of values indexed by id (integer) """ # REFERENCE: [MS-OLEPS] https://msdn.microsoft.com/en-us/library/dd942421.aspx # make sure no_conversion is a list, just to simplify code below: if no_conversion is None: no_conversion = [] # stream path as a string to report exceptions: streampath = filename if not isinstance(streampath, str): streampath = '/'.join(streampath) fp = self.openstream(filename) data = {} try: # header s = fp.read(28) clsid = _clsid(s[8:24]) # format id s = fp.read(20) fmtid = _clsid(s[:16]) fp.seek(i32(s, 16)) # get section s = b"****" + fp.read(i32(fp.read(4))-4) # number of properties: num_props = i32(s, 4) except BaseException as exc: # catch exception while parsing property header, and only raise # a DEFECT_INCORRECT then return an empty dict, because this is not # a fatal error when parsing the whole file msg = 'Error while parsing properties header in stream %s: %s' % ( repr(streampath), exc) self.raise_defect(DEFECT_INCORRECT, msg, type(exc)) return data for i in range(num_props): try: id = 0 # just in case of an exception id = i32(s, 8+i*8) offset = i32(s, 12+i*8) type = i32(s, offset) debug('property id=%d: type=%d offset=%X' % (id, type, offset)) # test for common types first (should perhaps use # a dictionary instead?) if type == VT_I2: # 16-bit signed integer value = i16(s, offset+4) if value >= 32768: value = value - 65536 elif type == VT_UI2: # 2-byte unsigned integer value = i16(s, offset+4) elif type in (VT_I4, VT_INT, VT_ERROR): # VT_I4: 32-bit signed integer # VT_ERROR: HRESULT, similar to 32-bit signed integer, # see http://msdn.microsoft.com/en-us/library/cc230330.aspx value = i32(s, offset+4) elif type in (VT_UI4, VT_UINT): # 4-byte unsigned integer value = i32(s, offset+4) # FIXME elif type in (VT_BSTR, VT_LPSTR): # CodePageString, see http://msdn.microsoft.com/en-us/library/dd942354.aspx # size is a 32 bits integer, including the null terminator, and # possibly trailing or embedded null chars #TODO: if codepage is unicode, the string should be converted as such count = i32(s, offset+4) value = s[offset+8:offset+8+count-1] # remove all null chars: value = value.replace(b'\x00', b'') elif type == VT_BLOB: # binary large object (BLOB) # see http://msdn.microsoft.com/en-us/library/dd942282.aspx count = i32(s, offset+4) value = s[offset+8:offset+8+count] elif type == VT_LPWSTR: # UnicodeString # see http://msdn.microsoft.com/en-us/library/dd942313.aspx # "the string should NOT contain embedded or additional trailing # null characters." count = i32(s, offset+4) value = self._decode_utf16_str(s[offset+8:offset+8+count*2]) elif type == VT_FILETIME: value = long(i32(s, offset+4)) + (long(i32(s, offset+8)) << 32) # FILETIME is a 64-bit int: "number of 100ns periods # since Jan 1,1601". if convert_time and id not in no_conversion: debug('Converting property #%d to python datetime, value=%d=%fs' % (id, value, float(value) / 10000000)) # convert FILETIME to Python datetime.datetime # inspired from http://code.activestate.com/recipes/511425-filetime-to-datetime/ _FILETIME_null_date = datetime.datetime(1601, 1, 1, 0, 0, 0) debug('timedelta days=%d' % (value//(10*1000000*3600*24))) value = _FILETIME_null_date + datetime.timedelta(microseconds=value//10) else: # legacy code kept for backward compatibility: returns a # number of seconds since Jan 1,1601 value = value // 10000000 # seconds elif type == VT_UI1: # 1-byte unsigned integer value = i8(s[offset+4]) elif type == VT_CLSID: value = _clsid(s[offset+4:offset+20]) elif type == VT_CF: # PropertyIdentifier or ClipboardData?? # see http://msdn.microsoft.com/en-us/library/dd941945.aspx count = i32(s, offset+4) value = s[offset+8:offset+8+count] elif type == VT_BOOL: # VARIANT_BOOL, 16 bits bool, 0x0000=Fals, 0xFFFF=True # see http://msdn.microsoft.com/en-us/library/cc237864.aspx value = bool(i16(s, offset+4)) else: value = None # everything else yields "None" debug('property id=%d: type=%d not implemented in parser yet' % (id, type)) # missing: VT_EMPTY, VT_NULL, VT_R4, VT_R8, VT_CY, VT_DATE, # VT_DECIMAL, VT_I1, VT_I8, VT_UI8, # see http://msdn.microsoft.com/en-us/library/dd942033.aspx # FIXME: add support for VT_VECTOR # VT_VECTOR is a 32 uint giving the number of items, followed by # the items in sequence. The VT_VECTOR value is combined with the # type of items, e.g. VT_VECTOR|VT_BSTR # see http://msdn.microsoft.com/en-us/library/dd942011.aspx # print("%08x" % id, repr(value), end=" ") # print("(%s)" % VT[i32(s, offset) & 0xFFF]) data[id] = value except BaseException as exc: # catch exception while parsing each property, and only raise # a DEFECT_INCORRECT, because parsing can go on msg = 'Error while parsing property id %d in stream %s: %s' % ( id, repr(streampath), exc) self.raise_defect(DEFECT_INCORRECT, msg, type(exc)) return data
[文档] def get_metadata(self): """ Parse standard properties streams, return an OleMetadata object containing all the available metadata. (also stored in the metadata attribute of the OleFileIO object) new in version 0.25 """ self.metadata = OleMetadata() self.metadata.parse_properties(self) return self.metadata
# # -------------------------------------------------------------------- # This script can be used to dump the directory of any OLE2 structured # storage file. if __name__ == "__main__": # [PL] display quick usage info if launched from command-line if len(sys.argv) <= 1: print('olefile version %s %s - %s' % (__version__, __date__, __author__)) print( """ Launched from the command line, this script parses OLE files and prints info. Usage: olefile.py [-d] [-c] <file> [file2 ...] Options: -d : debug mode (displays a lot of debug information, for developers only) -c : check all streams (for debugging purposes) For more information, see http://www.decalage.info/olefile """) sys.exit() check_streams = False for filename in sys.argv[1:]: # try: # OPTIONS: if filename == '-d': # option to switch debug mode on: set_debug_mode(True) continue if filename == '-c': # option to switch check streams mode on: check_streams = True continue ole = OleFileIO(filename)#, raise_defects=DEFECT_INCORRECT) print("-" * 68) print(filename) print("-" * 68) ole.dumpdirectory() for streamname in ole.listdir(): if streamname[-1][0] == "\005": print(streamname, ": properties") props = ole.getproperties(streamname, convert_time=True) props = sorted(props.items()) for k, v in props: # [PL]: avoid to display too large or binary values: if isinstance(v, (basestring, bytes)): if len(v) > 50: v = v[:50] if isinstance(v, bytes): # quick and dirty binary check: for c in (1, 2, 3, 4, 5, 6, 7, 11, 12, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31): if c in bytearray(v): v = '(binary data)' break print(" ", k, v) if check_streams: # Read all streams to check if there are errors: print('\nChecking streams...') for streamname in ole.listdir(): # print name using repr() to convert binary chars to \xNN: print('-', repr('/'.join(streamname)), '-', end=' ') st_type = ole.get_type(streamname) if st_type == STGTY_STREAM: print('size %d' % ole.get_size(streamname)) # just try to read stream in memory: ole.openstream(streamname) else: print('NOT a stream : type=%d' % st_type) print() # for streamname in ole.listdir(): # # print name using repr() to convert binary chars to \xNN: # print('-', repr('/'.join(streamname)),'-', end=' ') # print(ole.getmtime(streamname)) # print() print('Modification/Creation times of all directory entries:') for entry in ole.direntries: if entry is not None: print('- %s: mtime=%s ctime=%s' % (entry.name, entry.getmtime(), entry.getctime())) print() # parse and display metadata: meta = ole.get_metadata() meta.dump() print() # [PL] Test a few new methods: root = ole.get_rootentry_name() print('Root entry name: "%s"' % root) if ole.exists('worddocument'): print("This is a Word document.") print("type of stream 'WordDocument':", ole.get_type('worddocument')) print("size :", ole.get_size('worddocument')) if ole.exists('macros/vba'): print("This document may contain VBA macros.") # print parsing issues: print('\nNon-fatal issues raised during parsing:') if ole.parsing_issues: for exctype, msg in ole.parsing_issues: print('- %s: %s' % (exctype.__name__, msg)) else: print('None') ## except IOError as v: ## print("***", "cannot read", file, "-", v) # this code was developed while listening to The Wedding Present "Sea Monsters"