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import os
import mimetypes
import subprocess
import tempfile
import glob
import logging
import zipfile
import shutil
import hachoir_core
import pdfrw
import mat
import parser
import archive
class OpenDocumentStripper(archive.GenericArchiveStripper):
'''
An open document file is a zip, with xml file into.
The one that interest us is meta.xml
'''
def remove_folder(self, folder_list):
for folder in folder_list:
dirname = folder.split('/')[0]
try:
shutil.rmtree(dirname)
except:#Some folder or open document format are buggies
pass
self.folder_list = []
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.filename + parser.POSTFIX, 'w',
allowZip64=True)
folder_list = []
for item in zipin.namelist():
if os.path.basename(item) is not item:#add folders to folder_list
folder_list.insert(0, os.path.dirname(item))
if item.endswith('.xml') or item.startswith('manifest'):
if item != 'meta.xml':#contains the metadata
zipin.extract(item)
zipout.write(item)
mat.secure_remove(item)
elif item == 'mimetype':
zipin.extract(item)
#remove line meta.xml
zipout.write(item)
mat.secure_remove(item)
else:
zipin.extract(item)
if os.path.isfile(item):
try:
cfile = mat.create_class_file(item, 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(item)
except:
logging.info('%s\' fileformat is not supported' %
item)
if self.add2archive:
zipout.write(item)
mat.secure_remove(item)
zipout.comment = ''
logging.info('%s treated' % self.filename)
zipin.close()
zipout.close()
self.remove_folder(folder_list)
if self.backup is False:
mat.secure_remove(self.filename) #remove the old file
os.rename(self.filename + parser.POSTFIX, self.filename)
def is_clean(self):
zipin = zipfile.ZipFile(self.filename, 'r')
try:
zipin.getinfo('meta.xml')
except KeyError:#no meta.xml in the file
zipin.close()
czf = archive.ZipStripper(self.realname, self.filename,
self.parser, self.editor, self.backup, self.add2archive)
if czf.is_clean():
return True
else:
return False
return False
class TorrentStripper(parser.Generic_parser):
'''
A torrent file looks like:
-root
-start
-announce
-announce-list
-comment
-created_by
-creation_date
-encoding
-info
-end
'''
def remove_all(self):
for field in self.editor['root']:
if self._should_remove(field):
#FIXME : hachoir does not support torrent metadata editing :<
del self.editor['/root/' + field.name]
hachoir_core.field.writeIntoFile(self.editor,
self.filename + parser.POSTFIX)
if self.backup is False:
mat.secure_remove(self.filename) #remove the old file
os.rename(self.filename + parser.POSTFIX, self.filename)
def is_clean(self):
for field in self.editor['root']:
if self._should_remove(field):
return False
return True
def get_meta(self):
metadata = {}
for field in self.editor['root']:
if self._should_remove(field):
try:#FIXME
metadata[field.name] = field.value
except:
metadata[field.name] = 'harmful content'
return metadata
def _should_remove(self, field):
if field.name in ('comment', 'created_by', 'creation_date', 'info'):
return True
else:
return False
class PdfStripper(parser.Generic_parser):
'''
Represent a pdf file, with the help of pdfrw
'''
def __init__(self, filename, realname, backup):
self.filename = filename
self.backup = backup
self.realname = realname
self.shortname = os.path.basename(filename)
self.mime = mimetypes.guess_type(filename)[0]
self.trailer = pdfrw.PdfReader(self.filename)
self.writer = pdfrw.PdfWriter()
self.convert = 'gm convert -antialias -enhance %s %s'
def remove_all(self):
'''
Remove all the meta fields that are compromizing
'''
self.trailer.Info.Title = ''
self.trailer.Info.Author = ''
self.trailer.Info.Producer = ''
self.trailer.Info.Creator = ''
self.trailer.Info.CreationDate = ''
self.trailer.Info.ModDate = ''
self.writer.trailer = self.trailer
self.writer.write(self.filename + parser.POSTFIX)
if self.backup is False:
mat.secure_remove(self.filename) #remove the old file
os.rename(self.filename + parser.POSTFIX, self.filename)
def remove_all_ugly(self):
'''
Transform each pages into a jpg, clean them,
then re-assemble them into a new pdf
'''
output_file = self.realname + parser.POSTFIX + '.pdf'
_, self.tmpdir = tempfile.mkstemp()
subprocess.call(self.convert % (self.filename, self.tmpdir +
'temp.jpg'), shell=True)#Convert pages to jpg
for current_file in glob.glob(self.tmpdir + 'temp*'):
#Clean every jpg image
class_file = mat.create_class_file(current_file, False)
class_file.remove_all()
subprocess.call(self.convert % (self.tmpdir +
'temp.jpg*', output_file), shell=True)#Assemble jpg into pdf
for current_file in glob.glob(self.tmpdir + 'temp*'):
#remove jpg files
mat.secure_remove(current_file)
if self.backup is False:
mat.secure_remove(self.filename) #remove the old file
os.rename(output_file, self.filename)#rename the new
name = self.realname
else:
name = output_file
class_file = mat.create_class_file(name, False)
class_file.remove_all()
def is_clean(self):
'''
Check if the file is clean from harmful metadatas
'''
for field in self.trailer.Info:
if field != '':
return False
return True
def get_meta(self):
'''
return a dict with all the meta of the file
'''
metadata = {}
for key, value in self.trailer.Info.iteritems():
metadata[key[1:]] = value[1:-1]
return metadata
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