from inspect import Attribute from typing import Optional from app.utils.misc import read_config_bool from flask import current_app import os import re from base64 import urlsafe_b64encode, urlsafe_b64decode import pickle from cryptography.fernet import Fernet import hashlib import brotli import logging import cssutils from cssutils.css.cssstylesheet import CSSStyleSheet from cssutils.css.cssstylerule import CSSStyleRule # removes warnings from cssutils cssutils.log.setLevel(logging.CRITICAL) def get_rule_for_selector(stylesheet: CSSStyleSheet, selector: str) -> Optional[CSSStyleRule]: """Search for a rule that matches a given selector in a stylesheet. Args: stylesheet (CSSStyleSheet) -- the stylesheet to search selector (str) -- the selector to search for Returns: Optional[CSSStyleRule] -- the rule that matches the selector or None """ for rule in stylesheet.cssRules: if hasattr(rule, "selectorText") and selector == rule.selectorText: return rule return None class Config: def __init__(self, **kwargs): app_config = current_app.config self.url = os.getenv('WHOOGLE_CONFIG_URL', '') self.lang_search = os.getenv('WHOOGLE_CONFIG_SEARCH_LANGUAGE', '') self.lang_interface = os.getenv('WHOOGLE_CONFIG_LANGUAGE', '') self.style_modified = os.getenv( 'WHOOGLE_CONFIG_STYLE', '') self.block = os.getenv('WHOOGLE_CONFIG_BLOCK', '') self.block_title = os.getenv('WHOOGLE_CONFIG_BLOCK_TITLE', '') self.block_url = os.getenv('WHOOGLE_CONFIG_BLOCK_URL', '') self.country = os.getenv('WHOOGLE_CONFIG_COUNTRY', '') self.tbs = os.getenv('WHOOGLE_CONFIG_TIME_PERIOD', '') self.theme = os.getenv('WHOOGLE_CONFIG_THEME', 'system') self.safe = read_config_bool('WHOOGLE_CONFIG_SAFE') self.dark = read_config_bool('WHOOGLE_CONFIG_DARK') # deprecated self.alts = read_config_bool('WHOOGLE_CONFIG_ALTS') self.nojs = read_config_bool('WHOOGLE_CONFIG_NOJS') self.tor = read_config_bool('WHOOGLE_CONFIG_TOR') self.near = os.getenv('WHOOGLE_CONFIG_NEAR', '') self.new_tab = read_config_bool('WHOOGLE_CONFIG_NEW_TAB') self.view_image = read_config_bool('WHOOGLE_CONFIG_VIEW_IMAGE') self.get_only = read_config_bool('WHOOGLE_CONFIG_GET_ONLY') self.anon_view = read_config_bool('WHOOGLE_CONFIG_ANON_VIEW') self.preferences_encrypted = read_config_bool('WHOOGLE_CONFIG_PREFERENCES_ENCRYPTED') self.preferences_key = os.getenv('WHOOGLE_CONFIG_PREFERENCES_KEY', '') self.accept_language = False self.safe_keys = [ 'lang_search', 'lang_interface', 'country', 'theme', 'alts', 'new_tab', 'view_image', 'block', 'safe', 'nojs', 'anon_view', 'preferences_encrypted', 'tbs' ] # Skip setting custom config if there isn't one if kwargs: mutable_attrs = self.get_mutable_attrs() for attr in mutable_attrs: if attr in kwargs.keys(): setattr(self, attr, kwargs[attr]) elif attr not in kwargs.keys() and mutable_attrs[attr] == bool: setattr(self, attr, False) def __getitem__(self, name): return getattr(self, name) def __setitem__(self, name, value): return setattr(self, name, value) def __delitem__(self, name): return delattr(self, name) def __contains__(self, name): return hasattr(self, name) def get_mutable_attrs(self): return {name: type(attr) for name, attr in self.__dict__.items() if not name.startswith("__") and (type(attr) is bool or type(attr) is str)} def get_attrs(self): return {name: attr for name, attr in self.__dict__.items() if not name.startswith("__") and (type(attr) is bool or type(attr) is str)} @property def style(self) -> str: """Returns the default style updated with specified modifications. Returns: str -- the new style """ style_sheet = cssutils.parseString( open(os.path.join(current_app.config['STATIC_FOLDER'], 'css/variables.css')).read() ) modified_sheet = cssutils.parseString(self.style_modified) for rule in modified_sheet: rule_default = get_rule_for_selector(style_sheet, rule.selectorText) # if modified rule is in default stylesheet, update it if rule_default is not None: # TODO: update this in a smarter way to handle :root better # for now if we change a varialbe in :root all other default # variables need to be also present rule_default.style = rule.style # else add the new rule to the default stylesheet else: style_sheet.add(rule) return str(style_sheet.cssText, 'utf-8') @property def preferences(self) -> str: # if encryption key is not set will uncheck preferences encryption if self.preferences_encrypted: self.preferences_encrypted = bool(self.preferences_key) # add a tag for visibility if preferences token startswith 'e' it means # the token is encrypted, 'u' means the token is unencrypted and can be # used by other whoogle instances encrypted_flag = "e" if self.preferences_encrypted else 'u' preferences_digest = self._encode_preferences() return f"{encrypted_flag}{preferences_digest}" def is_safe_key(self, key) -> bool: """Establishes a group of config options that are safe to set in the url. Args: key (str) -- the key to check against Returns: bool -- True/False depending on if the key is in the "safe" array """ return key in self.safe_keys def get_localization_lang(self): """Returns the correct language to use for localization, but falls back to english if not set. Returns: str -- the localization language string """ if (self.lang_interface and self.lang_interface in current_app.config['TRANSLATIONS']): return self.lang_interface return 'lang_en' def from_params(self, params) -> 'Config': """Modify user config with search parameters. This is primarily used for specifying configuration on a search-by-search basis on public instances. Args: params -- the url arguments (can be any deemed safe by is_safe()) Returns: Config -- a modified config object """ if 'preferences' in params: params_new = self._decode_preferences(params['preferences']) # if preferences leads to an empty dictionary it means preferences # parameter was not decrypted successfully if len(params_new): params = params_new for param_key in params.keys(): if not self.is_safe_key(param_key): continue param_val = params.get(param_key) if param_val == 'off': param_val = False elif isinstance(param_val, str): if param_val.isdigit(): param_val = int(param_val) self[param_key] = param_val return self def to_params(self, keys: list = []) -> str: """Generates a set of safe params for using in Whoogle URLs Args: keys (list) -- optional list of keys of URL parameters Returns: str -- a set of URL parameters """ if not len(keys): keys = self.safe_keys param_str = '' for safe_key in keys: if not self[safe_key]: continue param_str = param_str + f'&{safe_key}={self[safe_key]}' return param_str def _get_fernet_key(self, password: str) -> bytes: hash_object = hashlib.md5(password.encode()) key = urlsafe_b64encode(hash_object.hexdigest().encode()) return key def _encode_preferences(self) -> str: encoded_preferences = brotli.compress(pickle.dumps(self.get_attrs())) if self.preferences_encrypted: if self.preferences_key != '': key = self._get_fernet_key(self.preferences_key) encoded_preferences = Fernet(key).encrypt(encoded_preferences) encoded_preferences = brotli.compress(encoded_preferences) return urlsafe_b64encode(encoded_preferences).decode() def _decode_preferences(self, preferences: str) -> dict: mode = preferences[0] preferences = preferences[1:] if mode == 'e': # preferences are encrypted try: key = self._get_fernet_key(self.preferences_key) config = Fernet(key).decrypt( brotli.decompress(urlsafe_b64decode( preferences.encode() + b'==')) ) config = pickle.loads(brotli.decompress(config)) except Exception: config = {} elif mode == 'u': # preferences are not encrypted config = pickle.loads( brotli.decompress(urlsafe_b64decode( preferences.encode() + b'==')) ) else: # preferences are incorrectly formatted config = {} return config