mat2 is a metadata removal tool, supporting a wide range of commonly used file formats, written in python3: at its core, it's a library, used by an eponymous command-line interface, and a nautilus extension.
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

236 lines
8.3 KiB

#!/usr/bin/env python3
import os
import shutil
from typing import Tuple, List, Union, Set
import sys
import mimetypes
import argparse
import logging
import unicodedata
import concurrent.futures
try:
from libmat2 import parser_factory, UNSUPPORTED_EXTENSIONS
from libmat2 import check_dependencies, UnknownMemberPolicy
except ValueError as e:
print(e)
sys.exit(1)
__version__ = '0.12.1'
# Make pyflakes happy
assert Set
assert Tuple
assert Union
logging.basicConfig(format='%(levelname)s: %(message)s', level=logging.WARNING)
def __check_file(filename: str, mode: int = os.R_OK) -> bool:
if not os.path.exists(filename):
print("[-] %s doesn't exist." % filename)
return False
elif not os.path.isfile(filename):
print("[-] %s is not a regular file." % filename)
return False
elif not os.access(filename, mode):
mode_str = [] # type: List[str]
if mode & os.R_OK:
mode_str += 'readable'
if mode & os.W_OK:
mode_str += 'writeable'
print("[-] %s is not %s." % (filename, 'nor '.join(mode_str)))
return False
return True
def create_arg_parser() -> argparse.ArgumentParser:
parser = argparse.ArgumentParser(description='Metadata anonymisation toolkit 2')
parser.add_argument('-V', '--verbose', action='store_true',
help='show more verbose status information')
parser.add_argument('--unknown-members', metavar='policy', default='abort',
help='how to handle unknown members of archive-style '
'files (policy should be one of: %s) [Default: abort]' %
', '.join(p.value for p in UnknownMemberPolicy))
parser.add_argument('--inplace', action='store_true',
help='clean in place, without backup')
parser.add_argument('--no-sandbox', dest='sandbox', action='store_true',
default=False, help='Disable bubblewrap\'s sandboxing')
excl_group = parser.add_mutually_exclusive_group()
excl_group.add_argument('files', nargs='*', help='the files to process',
default=[])
excl_group.add_argument('-v', '--version', action='version',
version='mat2 %s' % __version__)
excl_group.add_argument('-l', '--list', action='store_true', default=False,
help='list all supported fileformats')
excl_group.add_argument('--check-dependencies', action='store_true',
default=False,
help='check if mat2 has all the dependencies it '
'needs')
excl_group = parser.add_mutually_exclusive_group()
excl_group.add_argument('-L', '--lightweight', action='store_true',
help='remove SOME metadata')
excl_group.add_argument('-s', '--show', action='store_true',
help='list harmful metadata detectable by mat2 '
'without removing them')
return parser
def show_meta(filename: str, sandbox: bool):
if not __check_file(filename):
return
try:
p, mtype = parser_factory.get_parser(filename) # type: ignore
except ValueError as e:
print("[-] something went wrong when processing %s: %s" % (filename, e))
return
if p is None:
print("[-] %s's format (%s) is not supported" % (filename, mtype))
return
p.sandbox = sandbox
__print_meta(filename, p.get_meta())
def __print_meta(filename: str, metadata: dict, depth: int = 1):
padding = " " * depth*2
if not metadata:
print(padding + "No metadata found in %s." % filename)
return
print("[%s] Metadata for %s:" % ('+'*depth, filename))
for (k, v) in sorted(metadata.items()):
if isinstance(v, dict):
__print_meta(k, v, depth+1)
continue
# Remove control characters
# We might use 'Cc' instead of 'C', but better safe than sorry
# https://www.unicode.org/reports/tr44/#GC_Values_Table
try:
v = ''.join(ch for ch in v if not unicodedata.category(ch).startswith('C'))
except TypeError:
pass # for things that aren't iterable
try: # FIXME this is ugly.
print(padding + " %s: %s" % (k, v))
except UnicodeEncodeError:
print(padding + " %s: harmful content" % k)
def clean_meta(filename: str, is_lightweight: bool, inplace: bool, sandbox: bool,
policy: UnknownMemberPolicy) -> bool:
mode = (os.R_OK | os.W_OK) if inplace else os.R_OK
if not __check_file(filename, mode):
return False
try:
p, mtype = parser_factory.get_parser(filename) # type: ignore
except ValueError as e:
print("[-] something went wrong when cleaning %s: %s" % (filename, e))
return False
if p is None:
print("[-] %s's format (%s) is not supported" % (filename, mtype))
return False
p.unknown_member_policy = policy
p.lightweight_cleaning = is_lightweight
p.sandbox = sandbox
try:
logging.debug('Cleaning %s', filename)
ret = p.remove_all()
if ret is True:
shutil.copymode(filename, p.output_filename)
if inplace is True:
os.rename(p.output_filename, filename)
return ret
except RuntimeError as e:
print("[-] %s can't be cleaned: %s" % (filename, e))
return False
def show_parsers():
print('[+] Supported formats:')
formats = set() # Set[str]
for parser in parser_factory._get_parsers(): # type: ignore
for mtype in parser.mimetypes:
extensions = set() # Set[str]
for extension in mimetypes.guess_all_extensions(mtype):
if extension not in UNSUPPORTED_EXTENSIONS:
extensions.add(extension)
if not extensions:
# we're not supporting a single extension in the current
# mimetype, so there is not point in showing the mimetype at all
continue
formats.add(' - %s (%s)' % (mtype, ', '.join(extensions)))
print('\n'.join(sorted(formats)))
def __get_files_recursively(files: List[str]) -> List[str]:
ret = set() # type: Set[str]
for f in files:
if os.path.isdir(f):
for path, _, _files in os.walk(f):
for _f in _files:
fname = os.path.join(path, _f)
if __check_file(fname):
ret.add(fname)
elif __check_file(f):
ret.add(f)
return list(ret)
def main() -> int:
arg_parser = create_arg_parser()
args = arg_parser.parse_args()
if args.verbose:
logging.getLogger().setLevel(logging.DEBUG)
if not args.files:
if args.list:
show_parsers()
return 0
elif args.check_dependencies:
print("Dependencies for mat2 %s:" % __version__)
for key, value in sorted(check_dependencies().items()):
print('- %s: %s %s' % (key, 'yes' if value['found'] else 'no',
'(optional)' if not value['required'] else ''))
else:
arg_parser.print_help()
return 0
elif args.show:
for f in __get_files_recursively(args.files):
show_meta(f, args.sandbox)
return 0
else:
inplace = args.inplace
policy = UnknownMemberPolicy(args.unknown_members)
if policy == UnknownMemberPolicy.KEEP:
logging.warning('Keeping unknown member files may leak metadata in the resulting file!')
no_failure = True
files = __get_files_recursively(args.files)
# We have to use Processes instead of Threads, since
# we're using tempfile.mkdtemp, which isn't thread-safe.
with concurrent.futures.ProcessPoolExecutor() as executor:
futures = list()
for f in files:
future = executor.submit(clean_meta, f, args.lightweight,
inplace, args.sandbox, policy)
futures.append(future)
for future in concurrent.futures.as_completed(futures):
no_failure &= future.result()
return 0 if no_failure is True else -1
if __name__ == '__main__':
sys.exit(main())