core/homeassistant/auth/mfa_modules/notify.py

326 lines
11 KiB
Python

"""HMAC-based One-time Password auth module.
Sending HOTP through notify service
"""
import logging
from collections import OrderedDict
from typing import Any, Dict, Optional, Tuple, List # noqa: F401
import attr
import voluptuous as vol
from homeassistant.const import CONF_EXCLUDE, CONF_INCLUDE
from homeassistant.core import HomeAssistant, callback
from homeassistant.helpers import config_validation as cv
from . import MultiFactorAuthModule, MULTI_FACTOR_AUTH_MODULES, \
MULTI_FACTOR_AUTH_MODULE_SCHEMA, SetupFlow
REQUIREMENTS = ['pyotp==2.2.6']
CONF_MESSAGE = 'message'
CONFIG_SCHEMA = MULTI_FACTOR_AUTH_MODULE_SCHEMA.extend({
vol.Optional(CONF_INCLUDE): vol.All(cv.ensure_list, [cv.string]),
vol.Optional(CONF_EXCLUDE): vol.All(cv.ensure_list, [cv.string]),
vol.Optional(CONF_MESSAGE,
default='{} is your Home Assistant login code'): str
}, extra=vol.PREVENT_EXTRA)
STORAGE_VERSION = 1
STORAGE_KEY = 'auth_module.notify'
STORAGE_USERS = 'users'
STORAGE_USER_ID = 'user_id'
INPUT_FIELD_CODE = 'code'
_LOGGER = logging.getLogger(__name__)
def _generate_secret() -> str:
"""Generate a secret."""
import pyotp
return str(pyotp.random_base32())
def _generate_random() -> int:
"""Generate a 8 digit number."""
import pyotp
return int(pyotp.random_base32(length=8, chars=list('1234567890')))
def _generate_otp(secret: str, count: int) -> str:
"""Generate one time password."""
import pyotp
return str(pyotp.HOTP(secret).at(count))
def _verify_otp(secret: str, otp: str, count: int) -> bool:
"""Verify one time password."""
import pyotp
return bool(pyotp.HOTP(secret).verify(otp, count))
@attr.s(slots=True)
class NotifySetting:
"""Store notify setting for one user."""
secret = attr.ib(type=str, factory=_generate_secret) # not persistent
counter = attr.ib(type=int, factory=_generate_random) # not persistent
notify_service = attr.ib(type=Optional[str], default=None)
target = attr.ib(type=Optional[str], default=None)
_UsersDict = Dict[str, NotifySetting]
@MULTI_FACTOR_AUTH_MODULES.register('notify')
class NotifyAuthModule(MultiFactorAuthModule):
"""Auth module send hmac-based one time password by notify service."""
DEFAULT_TITLE = 'Notify One-Time Password'
def __init__(self, hass: HomeAssistant, config: Dict[str, Any]) -> None:
"""Initialize the user data store."""
super().__init__(hass, config)
self._user_settings = None # type: Optional[_UsersDict]
self._user_store = hass.helpers.storage.Store(
STORAGE_VERSION, STORAGE_KEY, private=True)
self._include = config.get(CONF_INCLUDE, [])
self._exclude = config.get(CONF_EXCLUDE, [])
self._message_template = config[CONF_MESSAGE]
@property
def input_schema(self) -> vol.Schema:
"""Validate login flow input data."""
return vol.Schema({INPUT_FIELD_CODE: str})
async def _async_load(self) -> None:
"""Load stored data."""
data = await self._user_store.async_load()
if data is None:
data = {STORAGE_USERS: {}}
self._user_settings = {
user_id: NotifySetting(**setting)
for user_id, setting in data.get(STORAGE_USERS, {}).items()
}
async def _async_save(self) -> None:
"""Save data."""
if self._user_settings is None:
return
await self._user_store.async_save({STORAGE_USERS: {
user_id: attr.asdict(
notify_setting, filter=attr.filters.exclude(
attr.fields(NotifySetting).secret,
attr.fields(NotifySetting).counter,
))
for user_id, notify_setting
in self._user_settings.items()
}})
@callback
def aync_get_available_notify_services(self) -> List[str]:
"""Return list of notify services."""
unordered_services = set()
for service in self.hass.services.async_services().get('notify', {}):
if service not in self._exclude:
unordered_services.add(service)
if self._include:
unordered_services &= set(self._include)
return sorted(unordered_services)
async def async_setup_flow(self, user_id: str) -> SetupFlow:
"""Return a data entry flow handler for setup module.
Mfa module should extend SetupFlow
"""
return NotifySetupFlow(
self, self.input_schema, user_id,
self.aync_get_available_notify_services())
async def async_setup_user(self, user_id: str, setup_data: Any) -> Any:
"""Set up auth module for user."""
if self._user_settings is None:
await self._async_load()
assert self._user_settings is not None
self._user_settings[user_id] = NotifySetting(
notify_service=setup_data.get('notify_service'),
target=setup_data.get('target'),
)
await self._async_save()
async def async_depose_user(self, user_id: str) -> None:
"""Depose auth module for user."""
if self._user_settings is None:
await self._async_load()
assert self._user_settings is not None
if self._user_settings.pop(user_id, None):
await self._async_save()
async def async_is_user_setup(self, user_id: str) -> bool:
"""Return whether user is setup."""
if self._user_settings is None:
await self._async_load()
assert self._user_settings is not None
return user_id in self._user_settings
async def async_validate(
self, user_id: str, user_input: Dict[str, Any]) -> bool:
"""Return True if validation passed."""
if self._user_settings is None:
await self._async_load()
assert self._user_settings is not None
notify_setting = self._user_settings.get(user_id, None)
if notify_setting is None:
return False
# user_input has been validate in caller
return await self.hass.async_add_executor_job(
_verify_otp, notify_setting.secret,
user_input.get(INPUT_FIELD_CODE, ''),
notify_setting.counter)
async def async_initialize_login_mfa_step(self, user_id: str) -> None:
"""Generate code and notify user."""
if self._user_settings is None:
await self._async_load()
assert self._user_settings is not None
notify_setting = self._user_settings.get(user_id, None)
if notify_setting is None:
raise ValueError('Cannot find user_id')
def generate_secret_and_one_time_password() -> str:
"""Generate and send one time password."""
assert notify_setting
# secret and counter are not persistent
notify_setting.secret = _generate_secret()
notify_setting.counter = _generate_random()
return _generate_otp(
notify_setting.secret, notify_setting.counter)
code = await self.hass.async_add_executor_job(
generate_secret_and_one_time_password)
await self.async_notify_user(user_id, code)
async def async_notify_user(self, user_id: str, code: str) -> None:
"""Send code by user's notify service."""
if self._user_settings is None:
await self._async_load()
assert self._user_settings is not None
notify_setting = self._user_settings.get(user_id, None)
if notify_setting is None:
_LOGGER.error('Cannot find user %s', user_id)
return
await self.async_notify( # type: ignore
code, notify_setting.notify_service, notify_setting.target)
async def async_notify(self, code: str, notify_service: str,
target: Optional[str] = None) -> None:
"""Send code by notify service."""
data = {'message': self._message_template.format(code)}
if target:
data['target'] = [target]
await self.hass.services.async_call('notify', notify_service, data)
class NotifySetupFlow(SetupFlow):
"""Handler for the setup flow."""
def __init__(self, auth_module: NotifyAuthModule,
setup_schema: vol.Schema,
user_id: str,
available_notify_services: List[str]) -> None:
"""Initialize the setup flow."""
super().__init__(auth_module, setup_schema, user_id)
# to fix typing complaint
self._auth_module = auth_module # type: NotifyAuthModule
self._available_notify_services = available_notify_services
self._secret = None # type: Optional[str]
self._count = None # type: Optional[int]
self._notify_service = None # type: Optional[str]
self._target = None # type: Optional[str]
async def async_step_init(
self, user_input: Optional[Dict[str, str]] = None) \
-> Dict[str, Any]:
"""Let user select available notify services."""
errors = {} # type: Dict[str, str]
hass = self._auth_module.hass
if user_input:
self._notify_service = user_input['notify_service']
self._target = user_input.get('target')
self._secret = await hass.async_add_executor_job(_generate_secret)
self._count = await hass.async_add_executor_job(_generate_random)
return await self.async_step_setup()
if not self._available_notify_services:
return self.async_abort(reason='no_available_service')
schema = OrderedDict() # type: Dict[str, Any]
schema['notify_service'] = vol.In(self._available_notify_services)
schema['target'] = vol.Optional(str)
return self.async_show_form(
step_id='init',
data_schema=vol.Schema(schema),
errors=errors
)
async def async_step_setup(
self, user_input: Optional[Dict[str, str]] = None) \
-> Dict[str, Any]:
"""Verify user can recevie one-time password."""
errors = {} # type: Dict[str, str]
hass = self._auth_module.hass
if user_input:
verified = await hass.async_add_executor_job(
_verify_otp, self._secret, user_input['code'], self._count)
if verified:
await self._auth_module.async_setup_user(
self._user_id, {
'notify_service': self._notify_service,
'target': self._target,
})
return self.async_create_entry(
title=self._auth_module.name,
data={}
)
errors['base'] = 'invalid_code'
# generate code every time, no retry logic
assert self._secret and self._count
code = await hass.async_add_executor_job(
_generate_otp, self._secret, self._count)
assert self._notify_service
await self._auth_module.async_notify(
code, self._notify_service, self._target)
return self.async_show_form(
step_id='setup',
data_schema=self._setup_schema,
description_placeholders={'notify_service': self._notify_service},
errors=errors,
)