undetected-chromedriver/undetected_chromedriver/patcher.py

#!/usr/bin/env python3
# this module is part of undetected_chromedriver

import io
import logging
import os
import random
import re
import string
import sys
import zipfile
from distutils.version import LooseVersion
from urllib.request import urlopen, urlretrieve
import secrets


logger = logging.getLogger(__name__)

IS_POSIX = sys.platform.startswith(("darwin", "cygwin", "linux"))


class Patcher(object):
    url_repo = "https://chromedriver.storage.googleapis.com"
    zip_name = "chromedriver_%s.zip"
    exe_name = "chromedriver%s"

    platform = sys.platform
    if platform.endswith("win32"):
        zip_name %= "win32"
        exe_name %= ".exe"
    if platform.endswith("linux"):
        zip_name %= "linux64"
        exe_name %= ""
    if platform.endswith("darwin"):
        zip_name %= "mac64"
        exe_name %= ""

    if platform.endswith("win32"):
        d = "~/appdata/roaming/undetected_chromedriver"
    elif platform.startswith("linux"):
        d = "~/.local/share/undetected_chromedriver"
    elif platform.endswith("darwin"):
        d = "~/Library/Application Support/undetected_chromedriver"
    else:
        d = "~/.undetected_chromedriver"
    data_path = os.path.abspath(os.path.expanduser(d))

    def __init__(self, executable_path=None, force=False, version_main: int = 0):
        """

        Args:
            executable_path: None = automatic
                             a full file path to the chromedriver executable
            force: False
                    terminate processes which are holding lock
            version_main: 0 = auto
                specify main chrome version (rounded, ex: 82)
        """

        self.force = force
        self.executable_path = None
        prefix = secrets.token_hex(8)

        if not executable_path:
            self.executable_path = os.path.join(
                self.data_path, "_".join([prefix, self.exe_name])
            )

        if not IS_POSIX:
            if executable_path:
                if not executable_path[-4:] == ".exe":
                    executable_path += ".exe"

        self.zip_path = os.path.join(self.data_path, self.zip_name)

        if not executable_path:
            self.executable_path = os.path.abspath(
                os.path.join(".", self.executable_path)
            )

        self._custom_exe_path = False

        if executable_path:
            self._custom_exe_path = True
            self.executable_path = executable_path
        self.version_main = version_main
        self.version_full = None

    def auto(self, executable_path=None, force=False, version_main=None):
        """"""
        if executable_path:
            self.executable_path = executable_path
            self._custom_exe_path = True

        if self._custom_exe_path:
            ispatched = self.is_binary_patched(self.executable_path)
            if not ispatched:
                return self.patch_exe()
            else:
                return

        if version_main:
            self.version_main = version_main
        if force is True:
            self.force = force

        try:
            os.unlink(self.executable_path)
        except PermissionError:
            if self.force:
                self.force_kill_instances(self.executable_path)
                return self.auto(force=not self.force)
            try:
                if self.is_binary_patched():
                    # assumes already running AND patched
                    return True
            except PermissionError:
                pass
            # return False
        except FileNotFoundError:
            pass

        release = self.fetch_release_number()
        self.version_main = release.version[0]
        self.version_full = release
        self.unzip_package(self.fetch_package())
        return self.patch()

    def patch(self):
        self.patch_exe()
        return self.is_binary_patched()

    def fetch_release_number(self):
        """
        Gets the latest major version available, or the latest major version of self.target_version if set explicitly.
        :return: version string
        :rtype: LooseVersion
        """
        path = "/latest_release"
        if self.version_main:
            path += f"_{self.version_main}"
        path = path.upper()
        logger.debug("getting release number from %s" % path)
        return LooseVersion(urlopen(self.url_repo + path).read().decode())

    def parse_exe_version(self):
        with io.open(self.executable_path, "rb") as f:
            for line in iter(lambda: f.readline(), b""):
                match = re.search(br"platform_handle\x00content\x00([0-9.]*)", line)
                if match:
                    return LooseVersion(match[1].decode())

    def fetch_package(self):
        """
        Downloads ChromeDriver from source

        :return: path to downloaded file
        """
        u = "%s/%s/%s" % (self.url_repo, self.version_full.vstring, self.zip_name)
        logger.debug("downloading from %s" % u)
        # return urlretrieve(u, filename=self.data_path)[0]
        return urlretrieve(u)[0]

    def unzip_package(self, fp):
        """
        Does what it says

        :return: path to unpacked executable
        """
        logger.debug("unzipping %s" % fp)
        try:
            os.unlink(self.zip_path)
        except (FileNotFoundError, OSError):
            pass

        os.makedirs(os.path.dirname(self.zip_path), mode=0o755, exist_ok=True)
        with zipfile.ZipFile(fp, mode="r") as zf:
            zf.extract(self.exe_name, os.path.dirname(self.zip_path))
        os.rename(
            os.path.join(self.data_path, self.exe_name),
            self.executable_path
        )
        os.remove(fp)
        os.chmod(self.executable_path, 0o755)
        return self.executable_path

    @staticmethod
    def force_kill_instances(exe_name):
        """
        kills running instances.
        :param: executable name to kill, may be a path as well

        :return: True on success else False
        """
        exe_name = os.path.basename(exe_name)
        if IS_POSIX:
            r = os.system("kill -f -9 $(pidof %s)" % exe_name)
        else:
            r = os.system("taskkill /f /im %s" % exe_name)
        return not r

    @staticmethod
    def gen_random_cdc():
        cdc = random.choices(string.ascii_lowercase, k=26)
        cdc[-6:-4] = map(str.upper, cdc[-6:-4])
        cdc[2] = cdc[0]
        cdc[3] = "_"
        return "".join(cdc).encode()

    def is_binary_patched(self, executable_path=None):
        """simple check if executable is patched.

        :return: False if not patched, else True
        """
        executable_path = executable_path or self.executable_path
        with io.open(executable_path, "rb") as fh:
            for line in iter(lambda: fh.readline(), b""):
                if b"cdc_" in line:
                    return False
            else:
                return True

    def patch_exe(self):
        """
        Patches the ChromeDriver binary

        :return: False on failure, binary name on success
        """
        logger.info("patching driver executable %s" % self.executable_path)

        linect = 0
        replacement = self.gen_random_cdc()
        with io.open(self.executable_path, "r+b") as fh:
            for line in iter(lambda: fh.readline(), b""):
                if b"cdc_" in line:
                    fh.seek(-len(line), 1)
                    newline = re.sub(b"cdc_.{22}", replacement, line)
                    fh.write(newline)
                    linect += 1
            return linect

    def __repr__(self):
        return "{0:s}({1:s})".format(
            self.__class__.__name__,
            self.executable_path,
        )

    def __del__(self):
        try:
            if not self._custom_exe_path:
                # we will not delete custom exe paths.
                # but this also voids support.
                # downloading and patching makes sure you never use the same $cdc values, see patch_exe()
                # after all, this program has a focus on detectability...
                os.unlink(self.executable_path)

        # except (OSError, RuntimeError, PermissionError):
        #     pass
        except:
            raise