diff options
Diffstat (limited to 'synapse/api/auth.py')
| -rw-r--r-- | synapse/api/auth.py | 193 |
1 files changed, 45 insertions, 148 deletions
diff --git a/synapse/api/auth.py b/synapse/api/auth.py index c037ccb984..6e6eaf3805 100644 --- a/synapse/api/auth.py +++ b/synapse/api/auth.py @@ -33,8 +33,6 @@ from synapse.http.site import SynapseRequest from synapse.logging.opentracing import active_span, force_tracing, start_active_span from synapse.storage.databases.main.registration import TokenLookupResult from synapse.types import Requester, UserID, create_requester -from synapse.util.caches.lrucache import LruCache -from synapse.util.macaroons import get_value_from_macaroon, satisfy_expiry if TYPE_CHECKING: from synapse.server import HomeServer @@ -46,10 +44,6 @@ logger = logging.getLogger(__name__) GUEST_DEVICE_ID = "guest_device" -class _InvalidMacaroonException(Exception): - pass - - class Auth: """ This class contains functions for authenticating users of our client-server API. @@ -61,14 +55,10 @@ class Auth: self.store = hs.get_datastores().main self._account_validity_handler = hs.get_account_validity_handler() self._storage_controllers = hs.get_storage_controllers() - - self.token_cache: LruCache[str, Tuple[str, bool]] = LruCache( - 10000, "token_cache" - ) + self._macaroon_generator = hs.get_macaroon_generator() self._track_appservice_user_ips = hs.config.appservice.track_appservice_user_ips self._track_puppeted_user_ips = hs.config.api.track_puppeted_user_ips - self._macaroon_secret_key = hs.config.key.macaroon_secret_key self._force_tracing_for_users = hs.config.tracing.force_tracing_for_users async def check_user_in_room( @@ -123,7 +113,6 @@ class Auth: self, request: SynapseRequest, allow_guest: bool = False, - rights: str = "access", allow_expired: bool = False, ) -> Requester: """Get a registered user's ID. @@ -132,7 +121,6 @@ class Auth: request: An HTTP request with an access_token query parameter. allow_guest: If False, will raise an AuthError if the user making the request is a guest. - rights: The operation being performed; the access token must allow this allow_expired: If True, allow the request through even if the account is expired, or session token lifetime has ended. Note that /login will deliver access tokens regardless of expiration. @@ -147,7 +135,7 @@ class Auth: parent_span = active_span() with start_active_span("get_user_by_req"): requester = await self._wrapped_get_user_by_req( - request, allow_guest, rights, allow_expired + request, allow_guest, allow_expired ) if parent_span: @@ -173,7 +161,6 @@ class Auth: self, request: SynapseRequest, allow_guest: bool, - rights: str, allow_expired: bool, ) -> Requester: """Helper for get_user_by_req @@ -211,7 +198,7 @@ class Auth: return requester user_info = await self.get_user_by_access_token( - access_token, rights, allow_expired=allow_expired + access_token, allow_expired=allow_expired ) token_id = user_info.token_id is_guest = user_info.is_guest @@ -391,15 +378,12 @@ class Auth: async def get_user_by_access_token( self, token: str, - rights: str = "access", allow_expired: bool = False, ) -> TokenLookupResult: """Validate access token and get user_id from it Args: token: The access token to get the user by - rights: The operation being performed; the access token must - allow this allow_expired: If False, raises an InvalidClientTokenError if the token is expired @@ -410,70 +394,55 @@ class Auth: is invalid """ - if rights == "access": - # First look in the database to see if the access token is present - # as an opaque token. - r = await self.store.get_user_by_access_token(token) - if r: - valid_until_ms = r.valid_until_ms - if ( - not allow_expired - and valid_until_ms is not None - and valid_until_ms < self.clock.time_msec() - ): - # there was a valid access token, but it has expired. - # soft-logout the user. - raise InvalidClientTokenError( - msg="Access token has expired", soft_logout=True - ) + # First look in the database to see if the access token is present + # as an opaque token. + r = await self.store.get_user_by_access_token(token) + if r: + valid_until_ms = r.valid_until_ms + if ( + not allow_expired + and valid_until_ms is not None + and valid_until_ms < self.clock.time_msec() + ): + # there was a valid access token, but it has expired. + # soft-logout the user. + raise InvalidClientTokenError( + msg="Access token has expired", soft_logout=True + ) - return r + return r # If the token isn't found in the database, then it could still be a - # macaroon, so we check that here. + # macaroon for a guest, so we check that here. try: - user_id, guest = self._parse_and_validate_macaroon(token, rights) - - if rights == "access": - if not guest: - # non-guest access tokens must be in the database - logger.warning("Unrecognised access token - not in store.") - raise InvalidClientTokenError() - - # Guest access tokens are not stored in the database (there can - # only be one access token per guest, anyway). - # - # In order to prevent guest access tokens being used as regular - # user access tokens (and hence getting around the invalidation - # process), we look up the user id and check that it is indeed - # a guest user. - # - # It would of course be much easier to store guest access - # tokens in the database as well, but that would break existing - # guest tokens. - stored_user = await self.store.get_user_by_id(user_id) - if not stored_user: - raise InvalidClientTokenError("Unknown user_id %s" % user_id) - if not stored_user["is_guest"]: - raise InvalidClientTokenError( - "Guest access token used for regular user" - ) - - ret = TokenLookupResult( - user_id=user_id, - is_guest=True, - # all guests get the same device id - device_id=GUEST_DEVICE_ID, + user_id = self._macaroon_generator.verify_guest_token(token) + + # Guest access tokens are not stored in the database (there can + # only be one access token per guest, anyway). + # + # In order to prevent guest access tokens being used as regular + # user access tokens (and hence getting around the invalidation + # process), we look up the user id and check that it is indeed + # a guest user. + # + # It would of course be much easier to store guest access + # tokens in the database as well, but that would break existing + # guest tokens. + stored_user = await self.store.get_user_by_id(user_id) + if not stored_user: + raise InvalidClientTokenError("Unknown user_id %s" % user_id) + if not stored_user["is_guest"]: + raise InvalidClientTokenError( + "Guest access token used for regular user" ) - elif rights == "delete_pusher": - # We don't store these tokens in the database - ret = TokenLookupResult(user_id=user_id, is_guest=False) - else: - raise RuntimeError("Unknown rights setting %s", rights) - return ret + return TokenLookupResult( + user_id=user_id, + is_guest=True, + # all guests get the same device id + device_id=GUEST_DEVICE_ID, + ) except ( - _InvalidMacaroonException, pymacaroons.exceptions.MacaroonException, TypeError, ValueError, @@ -485,78 +454,6 @@ class Auth: ) raise InvalidClientTokenError("Invalid access token passed.") - def _parse_and_validate_macaroon( - self, token: str, rights: str = "access" - ) -> Tuple[str, bool]: - """Takes a macaroon and tries to parse and validate it. This is cached - if and only if rights == access and there isn't an expiry. - - On invalid macaroon raises _InvalidMacaroonException - - Returns: - (user_id, is_guest) - """ - if rights == "access": - cached = self.token_cache.get(token, None) - if cached: - return cached - - try: - macaroon = pymacaroons.Macaroon.deserialize(token) - except Exception: # deserialize can throw more-or-less anything - # The access token doesn't look like a macaroon. - raise _InvalidMacaroonException() - - try: - user_id = get_value_from_macaroon(macaroon, "user_id") - - guest = False - for caveat in macaroon.caveats: - if caveat.caveat_id == "guest = true": - guest = True - - self.validate_macaroon(macaroon, rights, user_id=user_id) - except ( - pymacaroons.exceptions.MacaroonException, - KeyError, - TypeError, - ValueError, - ): - raise InvalidClientTokenError("Invalid macaroon passed.") - - if rights == "access": - self.token_cache[token] = (user_id, guest) - - return user_id, guest - - def validate_macaroon( - self, macaroon: pymacaroons.Macaroon, type_string: str, user_id: str - ) -> None: - """ - validate that a Macaroon is understood by and was signed by this server. - - Args: - macaroon: The macaroon to validate - type_string: The kind of token required (e.g. "access", "delete_pusher") - user_id: The user_id required - """ - v = pymacaroons.Verifier() - - # the verifier runs a test for every caveat on the macaroon, to check - # that it is met for the current request. Each caveat must match at - # least one of the predicates specified by satisfy_exact or - # specify_general. - v.satisfy_exact("gen = 1") - v.satisfy_exact("type = " + type_string) - v.satisfy_exact("user_id = %s" % user_id) - v.satisfy_exact("guest = true") - satisfy_expiry(v, self.clock.time_msec) - - # access_tokens include a nonce for uniqueness: any value is acceptable - v.satisfy_general(lambda c: c.startswith("nonce = ")) - - v.verify(macaroon, self._macaroon_secret_key) - def get_appservice_by_req(self, request: SynapseRequest) -> ApplicationService: token = self.get_access_token_from_request(request) service = self.store.get_app_service_by_token(token) |