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#!/usr/bin/python
'''
Metadata anonymisation toolkit library
'''
import hachoir_core.error
import hachoir_core.field
import hachoir_core.cmd_line
import hachoir_parser
import hachoir_metadata
import hachoir_editor
import sys
import os
import hachoir_parser.image
__version__ = "0.1"
__author__ = "jvoisin"
POSTFIX = ".cleaned"
class file():
def __init__(self, realname, filename, parser, editor):
self.meta = {}
self.filename = filename
self.realname = realname
self.parser = parser
self.editor = editor
self.meta = self.__fill_meta()
def __fill_meta(self):
metadata = {}
try:
meta = hachoir_metadata.extractMetadata(self.parser)
except hachoir_core.error.HachoirError, err:
print("Metadata extraction error: %s" % err)
if not meta:
print("Unable to extract metadata from the file %s" % self.filename)
sys.exit(1)
for title in meta:
#fixme i'm so dirty
if title.values != []: #if the field is not empty
value = ""
for item in title.values:
value = item.text
metadata[title.key] = value
return metadata
def is_clean(self):
'''
Check if the file is clean from harmful metadatas
'''
for field in self.editor:
if self._should_remove(field):
return False
return True
def remove_all(self):
'''
Remove all the files that are compromizing
'''
for field in self.editor:
if self._should_remove(field):
self._remove(field)
hachoir_core.field.writeIntoFile(self.editor, self.filename + POSTFIX)
def _remove(self, field):
'''
Remove the given field
'''
del self.editor[field.name]
def get_meta(self):
'''
return a dict with all the meta of the file
'''
#am I useless ?
return self.meta
def _should_remove(self, key):
'''
return True if the field is compromizing
abstract method
'''
raise NotImplementedError()
class JpegStripper(file):
def _should_remove(self, field):
if field.name.startswith('comment'):
return True
elif field.name in ("photoshop", "exif", "adobe"):
return True
else:
return False
class PngStripper(file):
def _should_remove(self, field):
if field.name in ('comment'):
return True
else:
return False
strippers = {
hachoir_parser.image.JpegFile: JpegStripper,
hachoir_parser.image.PngFile: PngStripper,
}
def create_class_file(name):
'''
return a $FILETYPEStripper() class,
corresponding to the filetype of the given file
'''
if not(os.path.isfile(name)): #check if the file exist
print("Error: %s is not a valid file" % name)
sys.exit(1)
filename = ""
realname = name
filename = hachoir_core.cmd_line.unicodeFilename(name)
parser = hachoir_parser.createParser(filename)
if not parser:
print("Unable to parse the file %s : sorry" % filename)
sys.exit(1)
editor = hachoir_editor.createEditor(parser)
try:
'''this part is a little tricky :
stripper_class will receice the name of the class $FILETYPEStripper,
(which herits from the "file" class), based on the editor
of given file (name)
'''
stripper_class = strippers[editor.input.__class__]
except KeyError:
#Place for another lib than hachoir
print("Don't have stripper for file type: %s" % editor.description)
sys.exit(1)
return stripper_class(realname, filename, parser, editor)
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