core/homeassistant/components/http/auth.py

239 lines
7.2 KiB
Python

"""Authentication for HTTP component."""
from __future__ import annotations
from collections.abc import Awaitable, Callable
from datetime import timedelta
from ipaddress import ip_address
import logging
import secrets
from typing import Any, Final
from aiohttp import hdrs
from aiohttp.web import Application, Request, StreamResponse, middleware
import jwt
from yarl import URL
from homeassistant.auth.const import GROUP_ID_READ_ONLY
from homeassistant.auth.models import User
from homeassistant.components import websocket_api
from homeassistant.core import HomeAssistant, callback
from homeassistant.helpers.storage import Store
from homeassistant.util import dt as dt_util
from homeassistant.util.network import is_local
from .const import KEY_AUTHENTICATED, KEY_HASS_REFRESH_TOKEN_ID, KEY_HASS_USER
from .request_context import current_request
_LOGGER = logging.getLogger(__name__)
DATA_API_PASSWORD: Final = "api_password"
DATA_SIGN_SECRET: Final = "http.auth.sign_secret"
SIGN_QUERY_PARAM: Final = "authSig"
SAFE_QUERY_PARAMS: Final = ["height", "width"]
STORAGE_VERSION = 1
STORAGE_KEY = "http.auth"
CONTENT_USER_NAME = "Home Assistant Content"
@callback
def async_sign_path(
hass: HomeAssistant,
path: str,
expiration: timedelta,
*,
refresh_token_id: str | None = None,
) -> str:
"""Sign a path for temporary access without auth header."""
if (secret := hass.data.get(DATA_SIGN_SECRET)) is None:
secret = hass.data[DATA_SIGN_SECRET] = secrets.token_hex()
if refresh_token_id is None:
if connection := websocket_api.current_connection.get():
refresh_token_id = connection.refresh_token_id
elif (
request := current_request.get()
) and KEY_HASS_REFRESH_TOKEN_ID in request:
refresh_token_id = request[KEY_HASS_REFRESH_TOKEN_ID]
else:
refresh_token_id = hass.data[STORAGE_KEY]
url = URL(path)
now = dt_util.utcnow()
params = dict(sorted(url.query.items()))
for param in SAFE_QUERY_PARAMS:
params.pop(param, None)
encoded = jwt.encode(
{
"iss": refresh_token_id,
"path": url.path,
"params": params,
"iat": now,
"exp": now + expiration,
},
secret,
algorithm="HS256",
)
params[SIGN_QUERY_PARAM] = encoded
url = url.with_query(params)
return f"{url.path}?{url.query_string}"
@callback
def async_user_not_allowed_do_auth(
hass: HomeAssistant, user: User, request: Request | None = None
) -> str | None:
"""Validate that user is not allowed to do auth things."""
if not user.is_active:
return "User is not active"
if not user.local_only:
return None
# User is marked as local only, check if they are allowed to do auth
if request is None:
request = current_request.get()
if not request:
return "No request available to validate local access"
if "cloud" in hass.config.components:
# pylint: disable=import-outside-toplevel
from hass_nabucasa import remote
if remote.is_cloud_request.get():
return "User is local only"
try:
remote = ip_address(request.remote) # type: ignore[arg-type]
except ValueError:
return "Invalid remote IP"
if is_local(remote):
return None
return "User cannot authenticate remotely"
async def async_setup_auth(hass: HomeAssistant, app: Application) -> None:
"""Create auth middleware for the app."""
store = Store[dict[str, Any]](hass, STORAGE_VERSION, STORAGE_KEY)
if (data := await store.async_load()) is None:
data = {}
refresh_token = None
if "content_user" in data:
user = await hass.auth.async_get_user(data["content_user"])
if user and user.refresh_tokens:
refresh_token = list(user.refresh_tokens.values())[0]
if refresh_token is None:
user = await hass.auth.async_create_system_user(
CONTENT_USER_NAME, group_ids=[GROUP_ID_READ_ONLY]
)
refresh_token = await hass.auth.async_create_refresh_token(user)
data["content_user"] = user.id
await store.async_save(data)
hass.data[STORAGE_KEY] = refresh_token.id
async def async_validate_auth_header(request: Request) -> bool:
"""
Test authorization header against access token.
Basic auth_type is legacy code, should be removed with api_password.
"""
try:
auth_type, auth_val = request.headers.get(hdrs.AUTHORIZATION, "").split(
" ", 1
)
except ValueError:
# If no space in authorization header
return False
if auth_type != "Bearer":
return False
refresh_token = await hass.auth.async_validate_access_token(auth_val)
if refresh_token is None:
return False
if async_user_not_allowed_do_auth(hass, refresh_token.user, request):
return False
request[KEY_HASS_USER] = refresh_token.user
request[KEY_HASS_REFRESH_TOKEN_ID] = refresh_token.id
return True
async def async_validate_signed_request(request: Request) -> bool:
"""Validate a signed request."""
if (secret := hass.data.get(DATA_SIGN_SECRET)) is None:
return False
if (signature := request.query.get(SIGN_QUERY_PARAM)) is None:
return False
try:
claims = jwt.decode(
signature, secret, algorithms=["HS256"], options={"verify_iss": False}
)
except jwt.InvalidTokenError:
return False
if claims["path"] != request.path:
return False
params = dict(sorted(request.query.items()))
del params[SIGN_QUERY_PARAM]
for param in SAFE_QUERY_PARAMS:
params.pop(param, None)
if claims["params"] != params:
return False
refresh_token = await hass.auth.async_get_refresh_token(claims["iss"])
if refresh_token is None:
return False
request[KEY_HASS_USER] = refresh_token.user
request[KEY_HASS_REFRESH_TOKEN_ID] = refresh_token.id
return True
@middleware
async def auth_middleware(
request: Request, handler: Callable[[Request], Awaitable[StreamResponse]]
) -> StreamResponse:
"""Authenticate as middleware."""
authenticated = False
if hdrs.AUTHORIZATION in request.headers and await async_validate_auth_header(
request
):
authenticated = True
auth_type = "bearer token"
# We first start with a string check to avoid parsing query params
# for every request.
elif (
request.method == "GET"
and SIGN_QUERY_PARAM in request.query_string
and await async_validate_signed_request(request)
):
authenticated = True
auth_type = "signed request"
if authenticated:
_LOGGER.debug(
"Authenticated %s for %s using %s",
request.remote,
request.path,
auth_type,
)
request[KEY_AUTHENTICATED] = authenticated
return await handler(request)
app.middlewares.append(auth_middleware)