file/magic/Magdir/msooxml

#------------------------------------------------------------------------------
# $File: msooxml,v 1.8 2018/05/24 18:11:17 christos Exp $
# msooxml:  file(1) magic for Microsoft Office XML
# From: Ralf Brown <ralf.brown@gmail.com>

# .docx, .pptx, and .xlsx are XML plus other files inside a ZIP
#   archive.  The first member file is normally "[Content_Types].xml".
#   but some libreoffice generated files put this later. Perhaps skip
#   the "[Content_Types].xml" test?
# Since MSOOXML doesn't have anything like the uncompressed "mimetype"
#   file of ePub or OpenDocument, we'll have to scan for a filename
#   which can distinguish between the three types

0		name		msooxml
>0		string		word/		Microsoft Word 2007+
!:mime application/vnd.openxmlformats-officedocument.wordprocessingml.document
>0		string		ppt/		Microsoft PowerPoint 2007+
!:mime application/vnd.openxmlformats-officedocument.presentationml.presentation
>0		string		xl/		Microsoft Excel 2007+
!:mime application/vnd.openxmlformats-officedocument.spreadsheetml.sheet

# start by checking for ZIP local file header signature
0		string		PK\003\004
!:strength +10
# make sure the first file is correct
>0x1E		use		msooxml
>0x1E		regex		\\[Content_Types\\]\\.xml|_rels/\\.rels
# skip to the second local file header
# since some documents include a 520-byte extra field following the file
# header, we need to scan for the next header
>>(18.l+49)	search/2000	PK\003\004
# now skip to the *third* local file header; again, we need to scan due to a
# 520-byte extra field following the file header
>>>&26		search/1000	PK\003\004
# and check the subdirectory name to determine which type of OOXML
# file we have.  Correct the mimetype with the registered ones:
# http://technet.microsoft.com/en-us/library/cc179224.aspx
>>>>&26		use		msooxml	
>>>>&26		default		x
# OpenOffice/Libreoffice orders ZIP entry differently, so check the 4th file
>>>>>&26	search/1000	PK\003\004
>>>>>>&26	use		msooxml	
>>>>>>&26	default		x		Microsoft OOXML