''' Care about office's formats ''' import os import logging import zipfile import fileinput try: import cairo import poppler except ImportError: pass import mat import parser import archive import pdfrw class OpenDocumentStripper(archive.GenericArchiveStripper): ''' An open document file is a zip, with xml file into. The one that interest us is meta.xml ''' def get_meta(self): ''' Return a dict with all the meta of the file by trying to read the meta.xml file. ''' zipin = zipfile.ZipFile(self.filename, 'r') metadata = {} try: content = zipin.read('meta.xml') zipin.close() metadata[self.filename] = 'harful meta' except KeyError: # no meta.xml file found logging.debug('%s has no opendocument metadata' % self.filename) return metadata def _remove_all(self, method): ''' FIXME ? There is a patch implementing the Zipfile.remove() method here : http://bugs.python.org/issue6818 ''' zipin = zipfile.ZipFile(self.filename, 'r') zipout = zipfile.ZipFile(self.output, 'w', allowZip64=True) for item in zipin.namelist(): name = os.path.join(self.tempdir, item) _, ext = os.path.splitext(name) if item.endswith('manifest.xml'): # contain the list of all files present in the archive zipin.extract(item, self.tempdir) for line in fileinput.input(name, inplace=1): #remove the line which contains "meta.xml" line = line.strip() if not 'meta.xml' in line: print line zipout.write(name, item) elif ext in parser.NOMETA or item == 'mimetype': #keep NOMETA files, and the "manifest" file if item != 'meta.xml': # contains the metadata zipin.extract(item, self.tempdir) zipout.write(name, item) else: zipin.extract(item, self.tempdir) if os.path.isfile(name): try: cfile = mat.create_class_file(name, False, self.add2archive) if method == 'normal': cfile.remove_all() else: cfile.remove_all_ugly() logging.debug('Processing %s from %s' % (item, self.filename)) zipout.write(name, item) except: logging.info('%s\' fileformat is not supported' % item) if self.add2archive: zipout.write(name, item) zipout.comment = '' logging.info('%s treated' % self.filename) zipin.close() zipout.close() self.do_backup() def is_clean(self): ''' Check if the file is clean from harmful metadatas ''' zipin = zipfile.ZipFile(self.filename, 'r') try: zipin.getinfo('meta.xml') except KeyError: # no meta.xml in the file czf = archive.ZipStripper(self.filename, self.parser, 'application/zip', self.backup, self.add2archive) if czf.is_clean(): zipin.close() return True zipin.close() return False class PdfStripper(parser.GenericParser): ''' Represent a pdf file ''' def __init__(self, filename, parser, mime, backup, add2archive): super(PdfStripper, self).__init__(filename, parser, mime, backup, add2archive) uri = 'file://' + os.path.abspath(self.filename) self.password = None self.document = poppler.document_new_from_file(uri, self.password) self.meta_list = ('title', 'author', 'subject', 'keywords', 'creator', 'producer', 'creation-date', 'mod-date', 'metadata') def is_clean(self): ''' Check if the file is clean from harmful metadatas ''' for key in self.meta_list: if key == 'creation-date' or key == 'mod-date': if self.document.get_property(key) != -1: return False elif self.document.get_property(key) is not None and \ self.document.get_property(key) != '': return False return True def remove_all(self): ''' Opening the pdf with poppler, then doing a render on a cairo pdfsurface for each pages. Thanks to Lunar^for the idea. http://cairographics.org/documentation/pycairo/2/ python-poppler is not documented at all : have fun ;) ''' page = self.document.get_page(0) page_width, page_height = page.get_size() surface = cairo.PDFSurface(self.output, page_width, page_height) context = cairo.Context(surface) # context draws on the surface logging.debug('Pdf rendering of %s' % self.filename) for pagenum in xrange(self.document.get_n_pages()): page = self.document.get_page(pagenum) context.translate(0, 0) page.render(context) # render the page on context context.show_page() # draw context on surface surface.finish() #For now, poppler cannot write meta, so we must use pdfrw logging.debug('Removing %s\'s superficial metadata' % self.filename) trailer = pdfrw.PdfReader(self.output) trailer.Info.Producer = trailer.Info.Creator = None writer = pdfrw.PdfWriter() writer.trailer = trailer writer.write(self.output) self.do_backup() def get_meta(self): ''' Return a dict with all the meta of the file ''' metadata = {} for key in self.meta_list: if key == 'creation-date' or key == 'mod-date': #creation and modification are set to -1 if self.document.get_property(key) != -1: metadata[key] = self.document.get_property(key) elif self.document.get_property(key) is not None and \ self.document.get_property(key) != '': metadata[key] = self.document.get_property(key) return metadata class OpenXmlStripper(archive.GenericArchiveStripper): ''' Represent an office openxml document, which is like an opendocument format, with some tricky stuff added. It contains mostly xml, but can have media blobs, crap, ... (I don't like this format.) ''' def _remove_all(self, method): ''' FIXME ? There is a patch implementing the Zipfile.remove() method here : http://bugs.python.org/issue6818 ''' zipin = zipfile.ZipFile(self.filename, 'r') zipout = zipfile.ZipFile(self.output, 'w', allowZip64=True) for item in zipin.namelist(): name = os.path.join(self.tempdir, item) _, ext = os.path.splitext(name) if item.startswith('docProps/'): # metadatas pass elif ext in parser.NOMETA or item == '.rels': #keep parser.NOMETA files, and the file named ".rels" zipin.extract(item, self.tempdir) zipout.write(name, item) else: zipin.extract(item, self.tempdir) if os.path.isfile(name): # don't care about folders try: cfile = mat.create_class_file(name, False, self.add2archive) if method == 'normal': cfile.remove_all() else: cfile.remove_all_ugly() logging.debug('Processing %s from %s' % (item, self.filename)) zipout.write(name, item) except: logging.info('%s\' fileformat is not supported' % item) if self.add2archive: zipout.write(name, item) zipout.comment = '' logging.info('%s treated' % self.filename) zipin.close() zipout.close() self.do_backup() def is_clean(self): ''' Check if the file is clean from harmful metadatas ''' zipin = zipfile.ZipFile(self.filename, 'r') for item in zipin.namelist(): if item.startswith('docProps/'): return False zipin.close() czf = archive.ZipStripper(self.filename, self.parser, 'application/zip', self.backup, self.add2archive) if not czf.is_clean(): return False else: return True def get_meta(self): ''' Return a dict with all the meta of the file ''' zipin = zipfile.ZipFile(self.filename, 'r') metadata = {} for item in zipin.namelist(): if item.startswith('docProps/'): metadata[item] = 'harmful content' zipin.close() return metadata