Refactoring.
This commit is contained in:
parent
659f37c90c
commit
e5d671c7c4
|
@ -1,7 +1,7 @@
|
|||
#!/usr/bin/env python3
|
||||
#
|
||||
# Copyright (C) 2016,2017 The University of Sheffield, UK
|
||||
#
|
||||
#
|
||||
# This program is free software: you can redistribute it and/or modify
|
||||
# it under the terms of the GNU General Public License as published by
|
||||
# the Free Software Foundation, either version 3 of the License, or
|
||||
|
@ -13,20 +13,20 @@
|
|||
# GNU General Public License for more details.
|
||||
#
|
||||
# You should have received a copy of the GNU General Public License
|
||||
# along with this program. If not, see <http://www.gnu.org/licenses/>.
|
||||
# along with this program. If not, see <https://www.gnu.org/licenses/>.
|
||||
#
|
||||
"""Utility functions for working with Chrome extensionsx archives,
|
||||
i.e., *.crx files."""
|
||||
|
||||
import io
|
||||
import zipfile
|
||||
import binascii
|
||||
|
||||
from Crypto.PublicKey import RSA
|
||||
from Crypto.Hash import SHA
|
||||
from Crypto.Signature import PKCS1_v1_5
|
||||
|
||||
import zipfile
|
||||
import io
|
||||
|
||||
|
||||
class CrxFile:
|
||||
"""Record class for storing crx files."""
|
||||
def __init__(self, filename, magic, version, pk_len, sig_len, pk, sig,
|
||||
header_len, data):
|
||||
self.file = filename
|
||||
|
@ -41,11 +41,12 @@ class CrxFile:
|
|||
|
||||
|
||||
def is_valid_magic(magic):
|
||||
return (b'Cr24' == magic)
|
||||
"""Check magic matches the magic bytes of the crx specificaton."""
|
||||
return magic == b'Cr24'
|
||||
|
||||
|
||||
def is_crxfile(filename):
|
||||
"Check magic number: crx files should start with \"Cr24\"."
|
||||
"""Check magic number: crx files should start with \"Cr24\"."""
|
||||
file = open(filename, 'rb')
|
||||
magic = file.read(4)
|
||||
file.close()
|
||||
|
@ -53,13 +54,14 @@ def is_crxfile(filename):
|
|||
|
||||
|
||||
def check_signature(pk, sig, data):
|
||||
"""Check validity of signature contained in the crx file."""
|
||||
key = RSA.importKey(pk)
|
||||
hash = SHA.new(data)
|
||||
return PKCS1_v1_5.new(key).verify(hash, sig)
|
||||
crxhash = SHA.new(data)
|
||||
return PKCS1_v1_5.new(key).verify(crxhash, sig)
|
||||
|
||||
|
||||
def read_crx(filename):
|
||||
"Read header of an crx file (https://developer.chrome.com/extensions/crx)."
|
||||
"""Read header of an crx file (https://developer.chrome.com/extensions/crx)."""
|
||||
file = open(filename, 'rb')
|
||||
magic = file.read(4)
|
||||
version = int.from_bytes(file.read(4), byteorder='little')
|
||||
|
@ -75,6 +77,7 @@ def read_crx(filename):
|
|||
|
||||
|
||||
def print_crx_info(verbose, crx):
|
||||
"""Print information extracted from a crx file."""
|
||||
if is_valid_magic(crx.magic):
|
||||
magic = "valid"
|
||||
else:
|
||||
|
@ -96,15 +99,16 @@ def print_crx_info(verbose, crx):
|
|||
if verbose:
|
||||
print("Signature [" + str(crx.sig_len) + "]: " + str(
|
||||
binascii.hexlify(crx.sig)))
|
||||
out = f = io.BytesIO(crx.data)
|
||||
zf = zipfile.ZipFile(out, 'r')
|
||||
out = io.BytesIO(crx.data)
|
||||
ziparchive = zipfile.ZipFile(out, 'r')
|
||||
print("Zip content:")
|
||||
for info in zf.infolist():
|
||||
for info in ziparchive.infolist():
|
||||
print('{:8d} {:8d}'.format(info.file_size, info.compress_size),
|
||||
info.filename)
|
||||
|
||||
|
||||
def verify_crxfile(verbose, filename):
|
||||
"""Verify integrity of a crx file."""
|
||||
if is_crxfile(filename):
|
||||
if verbose:
|
||||
print("Found correct magic bytes.")
|
||||
|
@ -117,17 +121,21 @@ def verify_crxfile(verbose, filename):
|
|||
|
||||
|
||||
def extract_crxfile(verbose, force, filename, destdir):
|
||||
"""Extract crxfile into specified destdir."""
|
||||
crx = read_crx(filename)
|
||||
if is_valid_magic(crx.magic) | force:
|
||||
if ("" == destdir) | (destdir is None):
|
||||
if (destdir == "") | (destdir is None):
|
||||
destdir = "."
|
||||
if filename.endswith(".crx"):
|
||||
dirname = filename[0:len(filename) - 4]
|
||||
else:
|
||||
dirname = filename
|
||||
out = f = io.BytesIO(crx.data)
|
||||
zf = zipfile.ZipFile(out, 'r')
|
||||
zf.extractall(destdir + "/" + dirname)
|
||||
print("Content extracted into: " + destdir + "/" + dirname)
|
||||
out = io.BytesIO(crx.data)
|
||||
ziparchive = zipfile.ZipFile(out, 'r')
|
||||
ziparchive.extractall(destdir + "/" + dirname)
|
||||
if verbose:
|
||||
print("Content extracted into: " + destdir + "/" + dirname)
|
||||
return 0
|
||||
else:
|
||||
print("Input file not valid.")
|
||||
return -1
|
||||
|
|
8
crx-tool
8
crx-tool
|
@ -1,7 +1,7 @@
|
|||
#!/usr/bin/env python3
|
||||
#
|
||||
# Copyright (C) 2016 The University of Sheffield, UK
|
||||
#
|
||||
#
|
||||
# This program is free software: you can redistribute it and/or modify
|
||||
# it under the terms of the GNU General Public License as published by
|
||||
# the Free Software Foundation, either version 3 of the License, or
|
||||
|
@ -15,11 +15,15 @@
|
|||
# You should have received a copy of the GNU General Public License
|
||||
# along with this program. If not, see <http://www.gnu.org/licenses/>.
|
||||
#
|
||||
""" A tool for analyzing and extracting `*.crx` files
|
||||
(i.e., Chrome extensions)."""
|
||||
|
||||
import argparse
|
||||
from ExtensionCrawler.crx import *
|
||||
from ExtensionCrawler.crx import extract_crxfile, verify_crxfile
|
||||
|
||||
|
||||
def main():
|
||||
"""Main function of the extension crawler."""
|
||||
parser = argparse.ArgumentParser()
|
||||
parser.add_argument("file", help="chrome extension archive (*.crx)")
|
||||
parser.add_argument('targetdir', nargs='?', default="")
|
||||
|
|
Loading…
Reference in New Issue