# -*- coding: utf-8 -*- # Copyright 2014 - 2016 OpenMarket Ltd # Copyright 2017 Vector Creations Ltd # Copyright 2019 - 2020 The Matrix.org Foundation C.I.C. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. import logging import time import unicodedata import urllib.parse from typing import ( TYPE_CHECKING, Any, Awaitable, Callable, Dict, Iterable, List, Mapping, Optional, Tuple, Union, ) import attr import bcrypt import pymacaroons from twisted.web.http import Request from synapse.api.constants import LoginType from synapse.api.errors import ( AuthError, Codes, InteractiveAuthIncompleteError, LoginError, StoreError, SynapseError, UserDeactivatedError, ) from synapse.api.ratelimiting import Ratelimiter from synapse.handlers._base import BaseHandler from synapse.handlers.ui_auth import INTERACTIVE_AUTH_CHECKERS from synapse.handlers.ui_auth.checkers import UserInteractiveAuthChecker from synapse.http import get_request_user_agent from synapse.http.server import finish_request, respond_with_html from synapse.http.site import SynapseRequest from synapse.logging.context import defer_to_thread from synapse.metrics.background_process_metrics import run_as_background_process from synapse.module_api import ModuleApi from synapse.types import JsonDict, Requester, UserID from synapse.util import stringutils as stringutils from synapse.util.async_helpers import maybe_awaitable from synapse.util.msisdn import phone_number_to_msisdn from synapse.util.threepids import canonicalise_email if TYPE_CHECKING: from synapse.app.homeserver import HomeServer logger = logging.getLogger(__name__) def convert_client_dict_legacy_fields_to_identifier( submission: JsonDict, ) -> Dict[str, str]: """ Convert a legacy-formatted login submission to an identifier dict. Legacy login submissions (used in both login and user-interactive authentication) provide user-identifying information at the top-level instead. These are now deprecated and replaced with identifiers: https://matrix.org/docs/spec/client_server/r0.6.1#identifier-types Args: submission: The client dict to convert Returns: The matching identifier dict Raises: SynapseError: If the format of the client dict is invalid """ identifier = submission.get("identifier", {}) # Generate an m.id.user identifier if "user" parameter is present user = submission.get("user") if user: identifier = {"type": "m.id.user", "user": user} # Generate an m.id.thirdparty identifier if "medium" and "address" parameters are present medium = submission.get("medium") address = submission.get("address") if medium and address: identifier = { "type": "m.id.thirdparty", "medium": medium, "address": address, } # We've converted valid, legacy login submissions to an identifier. If the # submission still doesn't have an identifier, it's invalid if not identifier: raise SynapseError(400, "Invalid login submission", Codes.INVALID_PARAM) # Ensure the identifier has a type if "type" not in identifier: raise SynapseError( 400, "'identifier' dict has no key 'type'", errcode=Codes.MISSING_PARAM, ) return identifier def login_id_phone_to_thirdparty(identifier: JsonDict) -> Dict[str, str]: """ Convert a phone login identifier type to a generic threepid identifier. Args: identifier: Login identifier dict of type 'm.id.phone' Returns: An equivalent m.id.thirdparty identifier dict """ if "country" not in identifier or ( # The specification requires a "phone" field, while Synapse used to require a "number" # field. Accept both for backwards compatibility. "phone" not in identifier and "number" not in identifier ): raise SynapseError( 400, "Invalid phone-type identifier", errcode=Codes.INVALID_PARAM ) # Accept both "phone" and "number" as valid keys in m.id.phone phone_number = identifier.get("phone", identifier["number"]) # Convert user-provided phone number to a consistent representation msisdn = phone_number_to_msisdn(identifier["country"], phone_number) return { "type": "m.id.thirdparty", "medium": "msisdn", "address": msisdn, } @attr.s(slots=True) class SsoLoginExtraAttributes: """Data we track about SAML2 sessions""" # time the session was created, in milliseconds creation_time = attr.ib(type=int) extra_attributes = attr.ib(type=JsonDict) class AuthHandler(BaseHandler): SESSION_EXPIRE_MS = 48 * 60 * 60 * 1000 def __init__(self, hs: "HomeServer"): super().__init__(hs) self.checkers = {} # type: Dict[str, UserInteractiveAuthChecker] for auth_checker_class in INTERACTIVE_AUTH_CHECKERS: inst = auth_checker_class(hs) if inst.is_enabled(): self.checkers[inst.AUTH_TYPE] = inst # type: ignore self.bcrypt_rounds = hs.config.bcrypt_rounds # we can't use hs.get_module_api() here, because to do so will create an # import loop. # # TODO: refactor this class to separate the lower-level stuff that # ModuleApi can use from the higher-level stuff that uses ModuleApi, as # better way to break the loop account_handler = ModuleApi(hs, self) self.password_providers = [ PasswordProvider.load(module, config, account_handler) for module, config in hs.config.password_providers ] logger.info("Extra password_providers: %s", self.password_providers) self.hs = hs # FIXME better possibility to access registrationHandler later? self.macaroon_gen = hs.get_macaroon_generator() self._password_enabled = hs.config.password_enabled self._password_localdb_enabled = hs.config.password_localdb_enabled # start out by assuming PASSWORD is enabled; we will remove it later if not. login_types = set() if self._password_localdb_enabled: login_types.add(LoginType.PASSWORD) for provider in self.password_providers: login_types.update(provider.get_supported_login_types().keys()) if not self._password_enabled: login_types.discard(LoginType.PASSWORD) # Some clients just pick the first type in the list. In this case, we want # them to use PASSWORD (rather than token or whatever), so we want to make sure # that comes first, where it's present. self._supported_login_types = [] if LoginType.PASSWORD in login_types: self._supported_login_types.append(LoginType.PASSWORD) login_types.remove(LoginType.PASSWORD) self._supported_login_types.extend(login_types) # Ratelimiter for failed auth during UIA. Uses same ratelimit config # as per `rc_login.failed_attempts`. self._failed_uia_attempts_ratelimiter = Ratelimiter( clock=self.clock, rate_hz=self.hs.config.rc_login_failed_attempts.per_second, burst_count=self.hs.config.rc_login_failed_attempts.burst_count, ) # The number of seconds to keep a UI auth session active. self._ui_auth_session_timeout = hs.config.ui_auth_session_timeout # Ratelimitier for failed /login attempts self._failed_login_attempts_ratelimiter = Ratelimiter( clock=hs.get_clock(), rate_hz=self.hs.config.rc_login_failed_attempts.per_second, burst_count=self.hs.config.rc_login_failed_attempts.burst_count, ) self._clock = self.hs.get_clock() # Expire old UI auth sessions after a period of time. if hs.config.run_background_tasks: self._clock.looping_call( run_as_background_process, 5 * 60 * 1000, "expire_old_sessions", self._expire_old_sessions, ) # Load the SSO HTML templates. # The following template is shown to the user during a client login via SSO, # after the SSO completes and before redirecting them back to their client. # It notifies the user they are about to give access to their matrix account # to the client. self._sso_redirect_confirm_template = hs.config.sso_redirect_confirm_template # The following template is shown during user interactive authentication # in the fallback auth scenario. It notifies the user that they are # authenticating for an operation to occur on their account. self._sso_auth_confirm_template = hs.config.sso_auth_confirm_template # The following template is shown after a successful user interactive # authentication session. It tells the user they can close the window. self._sso_auth_success_template = hs.config.sso_auth_success_template # The following template is shown during the SSO authentication process if # the account is deactivated. self._sso_account_deactivated_template = ( hs.config.sso_account_deactivated_template ) self._server_name = hs.config.server_name # cast to tuple for use with str.startswith self._whitelisted_sso_clients = tuple(hs.config.sso_client_whitelist) # A mapping of user ID to extra attributes to include in the login # response. self._extra_attributes = {} # type: Dict[str, SsoLoginExtraAttributes] async def validate_user_via_ui_auth( self, requester: Requester, request: SynapseRequest, request_body: Dict[str, Any], description: str, ) -> Tuple[dict, Optional[str]]: """ Checks that the user is who they claim to be, via a UI auth. This is used for things like device deletion and password reset where the user already has a valid access token, but we want to double-check that it isn't stolen by re-authenticating them. Args: requester: The user, as given by the access token request: The request sent by the client. request_body: The body of the request sent by the client description: A human readable string to be displayed to the user that describes the operation happening on their account. Returns: A tuple of (params, session_id). 'params' contains the parameters for this request (which may have been given only in a previous call). 'session_id' is the ID of this session, either passed in by the client or assigned by this call. This is None if UI auth was skipped (by re-using a previous validation). Raises: InteractiveAuthIncompleteError if the client has not yet completed any of the permitted login flows AuthError if the client has completed a login flow, and it gives a different user to `requester` LimitExceededError if the ratelimiter's failed request count for this user is too high to proceed """ if self._ui_auth_session_timeout: last_validated = await self.store.get_access_token_last_validated( requester.access_token_id ) if self.clock.time_msec() - last_validated < self._ui_auth_session_timeout: # Return the input parameters, minus the auth key, which matches # the logic in check_ui_auth. request_body.pop("auth", None) return request_body, None user_id = requester.user.to_string() # Check if we should be ratelimited due to too many previous failed attempts self._failed_uia_attempts_ratelimiter.ratelimit(user_id, update=False) # build a list of supported flows supported_ui_auth_types = await self._get_available_ui_auth_types( requester.user ) flows = [[login_type] for login_type in supported_ui_auth_types] try: result, params, session_id = await self.check_ui_auth( flows, request, request_body, description ) except LoginError: # Update the ratelimiter to say we failed (`can_do_action` doesn't raise). self._failed_uia_attempts_ratelimiter.can_do_action(user_id) raise # find the completed login type for login_type in supported_ui_auth_types: if login_type not in result: continue user_id = result[login_type] break else: # this can't happen raise Exception("check_auth returned True but no successful login type") # check that the UI auth matched the access token if user_id != requester.user.to_string(): raise AuthError(403, "Invalid auth") # Note that the access token has been validated. await self.store.update_access_token_last_validated(requester.access_token_id) return params, session_id async def _get_available_ui_auth_types(self, user: UserID) -> Iterable[str]: """Get a list of the authentication types this user can use """ ui_auth_types = set() # if the HS supports password auth, and the user has a non-null password, we # support password auth if self._password_localdb_enabled and self._password_enabled: lookupres = await self._find_user_id_and_pwd_hash(user.to_string()) if lookupres: _, password_hash = lookupres if password_hash: ui_auth_types.add(LoginType.PASSWORD) # also allow auth from password providers for provider in self.password_providers: for t in provider.get_supported_login_types().keys(): if t == LoginType.PASSWORD and not self._password_enabled: continue ui_auth_types.add(t) # if sso is enabled, allow the user to log in via SSO iff they have a mapping # from sso to mxid. if self.hs.config.saml2.saml2_enabled or self.hs.config.oidc.oidc_enabled: if await self.store.get_external_ids_by_user(user.to_string()): ui_auth_types.add(LoginType.SSO) # Our CAS impl does not (yet) correctly register users in user_external_ids, # so always offer that if it's available. if self.hs.config.cas.cas_enabled: ui_auth_types.add(LoginType.SSO) return ui_auth_types def get_enabled_auth_types(self): """Return the enabled user-interactive authentication types Returns the UI-Auth types which are supported by the homeserver's current config. """ return self.checkers.keys() async def check_ui_auth( self, flows: List[List[str]], request: SynapseRequest, clientdict: Dict[str, Any], description: str, ) -> Tuple[dict, dict, str]: """ Takes a dictionary sent by the client in the login / registration protocol and handles the User-Interactive Auth flow. If no auth flows have been completed successfully, raises an InteractiveAuthIncompleteError. To handle this, you can use synapse.rest.client.v2_alpha._base.interactive_auth_handler as a decorator. Args: flows: A list of login flows. Each flow is an ordered list of strings representing auth-types. At least one full flow must be completed in order for auth to be successful. request: The request sent by the client. clientdict: The dictionary from the client root level, not the 'auth' key: this method prompts for auth if none is sent. description: A human readable string to be displayed to the user that describes the operation happening on their account. Returns: A tuple of (creds, params, session_id). 'creds' contains the authenticated credentials of each stage. 'params' contains the parameters for this request (which may have been given only in a previous call). 'session_id' is the ID of this session, either passed in by the client or assigned by this call Raises: InteractiveAuthIncompleteError if the client has not yet completed all the stages in any of the permitted flows. """ sid = None # type: Optional[str] authdict = clientdict.pop("auth", {}) if "session" in authdict: sid = authdict["session"] # Convert the URI and method to strings. uri = request.uri.decode("utf-8") method = request.method.decode("utf-8") # If there's no session ID, create a new session. if not sid: session = await self.store.create_ui_auth_session( clientdict, uri, method, description ) else: try: session = await self.store.get_ui_auth_session(sid) except StoreError: raise SynapseError(400, "Unknown session ID: %s" % (sid,)) # If the client provides parameters, update what is persisted, # otherwise use whatever was last provided. # # This was designed to allow the client to omit the parameters # and just supply the session in subsequent calls so it split # auth between devices by just sharing the session, (eg. so you # could continue registration from your phone having clicked the # email auth link on there). It's probably too open to abuse # because it lets unauthenticated clients store arbitrary objects # on a homeserver. # # Revisit: Assuming the REST APIs do sensible validation, the data # isn't arbitrary. # # Note that the registration endpoint explicitly removes the # "initial_device_display_name" parameter if it is provided # without a "password" parameter. See the changes to # synapse.rest.client.v2_alpha.register.RegisterRestServlet.on_POST # in commit 544722bad23fc31056b9240189c3cbbbf0ffd3f9. if not clientdict: clientdict = session.clientdict # Ensure that the queried operation does not vary between stages of # the UI authentication session. This is done by generating a stable # comparator and storing it during the initial query. Subsequent # queries ensure that this comparator has not changed. # # The comparator is based on the requested URI and HTTP method. The # client dict (minus the auth dict) should also be checked, but some # clients are not spec compliant, just warn for now if the client # dict changes. if (session.uri, session.method) != (uri, method): raise SynapseError( 403, "Requested operation has changed during the UI authentication session.", ) if session.clientdict != clientdict: logger.warning( "Requested operation has changed during the UI " "authentication session. A future version of Synapse " "will remove this capability." ) # For backwards compatibility, changes to the client dict are # persisted as clients modify them throughout their user interactive # authentication flow. await self.store.set_ui_auth_clientdict(sid, clientdict) user_agent = get_request_user_agent(request) clientip = request.getClientIP() await self.store.add_user_agent_ip_to_ui_auth_session( session.session_id, user_agent, clientip ) if not authdict: raise InteractiveAuthIncompleteError( session.session_id, self._auth_dict_for_flows(flows, session.session_id) ) # check auth type currently being presented errordict = {} # type: Dict[str, Any] if "type" in authdict: login_type = authdict["type"] # type: str try: result = await self._check_auth_dict(authdict, clientip) if result: await self.store.mark_ui_auth_stage_complete( session.session_id, login_type, result ) except LoginError as e: if login_type == LoginType.EMAIL_IDENTITY: # riot used to have a bug where it would request a new # validation token (thus sending a new email) each time it # got a 401 with a 'flows' field. # (https://github.com/vector-im/vector-web/issues/2447). # # Grandfather in the old behaviour for now to avoid # breaking old riot deployments. raise # this step failed. Merge the error dict into the response # so that the client can have another go. errordict = e.error_dict() creds = await self.store.get_completed_ui_auth_stages(session.session_id) for f in flows: # If all the required credentials have been supplied, the user has # successfully completed the UI auth process! if len(set(f) - set(creds)) == 0: # it's very useful to know what args are stored, but this can # include the password in the case of registering, so only log # the keys (confusingly, clientdict may contain a password # param, creds is just what the user authed as for UI auth # and is not sensitive). logger.info( "Auth completed with creds: %r. Client dict has keys: %r", creds, list(clientdict), ) return creds, clientdict, session.session_id ret = self._auth_dict_for_flows(flows, session.session_id) ret["completed"] = list(creds) ret.update(errordict) raise InteractiveAuthIncompleteError(session.session_id, ret) async def add_oob_auth( self, stagetype: str, authdict: Dict[str, Any], clientip: str ) -> bool: """ Adds the result of out-of-band authentication into an existing auth session. Currently used for adding the result of fallback auth. """ if stagetype not in self.checkers: raise LoginError(400, "", Codes.MISSING_PARAM) if "session" not in authdict: raise LoginError(400, "", Codes.MISSING_PARAM) result = await self.checkers[stagetype].check_auth(authdict, clientip) if result: await self.store.mark_ui_auth_stage_complete( authdict["session"], stagetype, result ) return True return False def get_session_id(self, clientdict: Dict[str, Any]) -> Optional[str]: """ Gets the session ID for a client given the client dictionary Args: clientdict: The dictionary sent by the client in the request Returns: The string session ID the client sent. If the client did not send a session ID, returns None. """ sid = None if clientdict and "auth" in clientdict: authdict = clientdict["auth"] if "session" in authdict: sid = authdict["session"] return sid async def set_session_data(self, session_id: str, key: str, value: Any) -> None: """ Store a key-value pair into the sessions data associated with this request. This data is stored server-side and cannot be modified by the client. Args: session_id: The ID of this session as returned from check_auth key: The key to store the data under value: The data to store """ try: await self.store.set_ui_auth_session_data(session_id, key, value) except StoreError: raise SynapseError(400, "Unknown session ID: %s" % (session_id,)) async def get_session_data( self, session_id: str, key: str, default: Optional[Any] = None ) -> Any: """ Retrieve data stored with set_session_data Args: session_id: The ID of this session as returned from check_auth key: The key to store the data under default: Value to return if the key has not been set """ try: return await self.store.get_ui_auth_session_data(session_id, key, default) except StoreError: raise SynapseError(400, "Unknown session ID: %s" % (session_id,)) async def _expire_old_sessions(self): """ Invalidate any user interactive authentication sessions that have expired. """ now = self._clock.time_msec() expiration_time = now - self.SESSION_EXPIRE_MS await self.store.delete_old_ui_auth_sessions(expiration_time) async def _check_auth_dict( self, authdict: Dict[str, Any], clientip: str ) -> Union[Dict[str, Any], str]: """Attempt to validate the auth dict provided by a client Args: authdict: auth dict provided by the client clientip: IP address of the client Returns: Result of the stage verification. Raises: StoreError if there was a problem accessing the database SynapseError if there was a problem with the request LoginError if there was an authentication problem. """ login_type = authdict["type"] checker = self.checkers.get(login_type) if checker is not None: res = await checker.check_auth(authdict, clientip=clientip) return res # fall back to the v1 login flow canonical_id, _ = await self.validate_login(authdict) return canonical_id def _get_params_recaptcha(self) -> dict: return {"public_key": self.hs.config.recaptcha_public_key} def _get_params_terms(self) -> dict: return { "policies": { "privacy_policy": { "version": self.hs.config.user_consent_version, "en": { "name": self.hs.config.user_consent_policy_name, "url": "%s_matrix/consent?v=%s" % ( self.hs.config.public_baseurl, self.hs.config.user_consent_version, ), }, } } } def _auth_dict_for_flows( self, flows: List[List[str]], session_id: str, ) -> Dict[str, Any]: public_flows = [] for f in flows: public_flows.append(f) get_params = { LoginType.RECAPTCHA: self._get_params_recaptcha, LoginType.TERMS: self._get_params_terms, } params = {} # type: Dict[str, Any] for f in public_flows: for stage in f: if stage in get_params and stage not in params: params[stage] = get_params[stage]() return { "session": session_id, "flows": [{"stages": f} for f in public_flows], "params": params, } async def get_access_token_for_user_id( self, user_id: str, device_id: Optional[str], valid_until_ms: Optional[int], puppets_user_id: Optional[str] = None, is_appservice_ghost: bool = False, ) -> str: """ Creates a new access token for the user with the given user ID. The user is assumed to have been authenticated by some other mechanism (e.g. CAS), and the user_id converted to the canonical case. The device will be recorded in the table if it is not there already. Args: user_id: canonical User ID device_id: the device ID to associate with the tokens. None to leave the tokens unassociated with a device (deprecated: we should always have a device ID) valid_until_ms: when the token is valid until. None for no expiry. is_appservice_ghost: Whether the user is an application ghost user Returns: The access token for the user's session. Raises: StoreError if there was a problem storing the token. """ fmt_expiry = "" if valid_until_ms is not None: fmt_expiry = time.strftime( " until %Y-%m-%d %H:%M:%S", time.localtime(valid_until_ms / 1000.0) ) if puppets_user_id: logger.info( "Logging in user %s as %s%s", user_id, puppets_user_id, fmt_expiry ) else: logger.info( "Logging in user %s on device %s%s", user_id, device_id, fmt_expiry ) if ( not is_appservice_ghost or self.hs.config.appservice.track_appservice_user_ips ): await self.auth.check_auth_blocking(user_id) access_token = self.macaroon_gen.generate_access_token(user_id) await self.store.add_access_token_to_user( user_id=user_id, token=access_token, device_id=device_id, valid_until_ms=valid_until_ms, puppets_user_id=puppets_user_id, ) # the device *should* have been registered before we got here; however, # it's possible we raced against a DELETE operation. The thing we # really don't want is active access_tokens without a record of the # device, so we double-check it here. if device_id is not None: try: await self.store.get_device(user_id, device_id) except StoreError: await self.store.delete_access_token(access_token) raise StoreError(400, "Login raced against device deletion") return access_token async def check_user_exists(self, user_id: str) -> Optional[str]: """ Checks to see if a user with the given id exists. Will check case insensitively, but return None if there are multiple inexact matches. Args: user_id: complete @user:id Returns: The canonical_user_id, or None if zero or multiple matches """ res = await self._find_user_id_and_pwd_hash(user_id) if res is not None: return res[0] return None async def _find_user_id_and_pwd_hash( self, user_id: str ) -> Optional[Tuple[str, str]]: """Checks to see if a user with the given id exists. Will check case insensitively, but will return None if there are multiple inexact matches. Returns: A 2-tuple of `(canonical_user_id, password_hash)` or `None` if there is not exactly one match """ user_infos = await self.store.get_users_by_id_case_insensitive(user_id) result = None if not user_infos: logger.warning("Attempted to login as %s but they do not exist", user_id) elif len(user_infos) == 1: # a single match (possibly not exact) result = user_infos.popitem() elif user_id in user_infos: # multiple matches, but one is exact result = (user_id, user_infos[user_id]) else: # multiple matches, none of them exact logger.warning( "Attempted to login as %s but it matches more than one user " "inexactly: %r", user_id, user_infos.keys(), ) return result def get_supported_login_types(self) -> Iterable[str]: """Get a the login types supported for the /login API By default this is just 'm.login.password' (unless password_enabled is False in the config file), but password auth providers can provide other login types. Returns: login types """ return self._supported_login_types async def validate_login( self, login_submission: Dict[str, Any], ratelimit: bool = False, ) -> Tuple[str, Optional[Callable[[Dict[str, str]], Awaitable[None]]]]: """Authenticates the user for the /login API Also used by the user-interactive auth flow to validate auth types which don't have an explicit UIA handler, including m.password.auth. Args: login_submission: the whole of the login submission (including 'type' and other relevant fields) ratelimit: whether to apply the failed_login_attempt ratelimiter Returns: A tuple of the canonical user id, and optional callback to be called once the access token and device id are issued Raises: StoreError if there was a problem accessing the database SynapseError if there was a problem with the request LoginError if there was an authentication problem. """ login_type = login_submission.get("type") if not isinstance(login_type, str): raise SynapseError(400, "Bad parameter: type", Codes.INVALID_PARAM) # ideally, we wouldn't be checking the identifier unless we know we have a login # method which uses it (https://github.com/matrix-org/synapse/issues/8836) # # But the auth providers' check_auth interface requires a username, so in # practice we can only support login methods which we can map to a username # anyway. # special case to check for "password" for the check_password interface # for the auth providers password = login_submission.get("password") if login_type == LoginType.PASSWORD: if not self._password_enabled: raise SynapseError(400, "Password login has been disabled.") if not isinstance(password, str): raise SynapseError(400, "Bad parameter: password", Codes.INVALID_PARAM) # map old-school login fields into new-school "identifier" fields. identifier_dict = convert_client_dict_legacy_fields_to_identifier( login_submission ) # convert phone type identifiers to generic threepids if identifier_dict["type"] == "m.id.phone": identifier_dict = login_id_phone_to_thirdparty(identifier_dict) # convert threepid identifiers to user IDs if identifier_dict["type"] == "m.id.thirdparty": address = identifier_dict.get("address") medium = identifier_dict.get("medium") if medium is None or address is None: raise SynapseError(400, "Invalid thirdparty identifier") # For emails, canonicalise the address. # We store all email addresses canonicalised in the DB. # (See add_threepid in synapse/handlers/auth.py) if medium == "email": try: address = canonicalise_email(address) except ValueError as e: raise SynapseError(400, str(e)) # We also apply account rate limiting using the 3PID as a key, as # otherwise using 3PID bypasses the ratelimiting based on user ID. if ratelimit: self._failed_login_attempts_ratelimiter.ratelimit( (medium, address), update=False ) # Check for login providers that support 3pid login types if login_type == LoginType.PASSWORD: # we've already checked that there is a (valid) password field assert isinstance(password, str) ( canonical_user_id, callback_3pid, ) = await self.check_password_provider_3pid(medium, address, password) if canonical_user_id: # Authentication through password provider and 3pid succeeded return canonical_user_id, callback_3pid # No password providers were able to handle this 3pid # Check local store user_id = await self.hs.get_datastore().get_user_id_by_threepid( medium, address ) if not user_id: logger.warning( "unknown 3pid identifier medium %s, address %r", medium, address ) # We mark that we've failed to log in here, as # `check_password_provider_3pid` might have returned `None` due # to an incorrect password, rather than the account not # existing. # # If it returned None but the 3PID was bound then we won't hit # this code path, which is fine as then the per-user ratelimit # will kick in below. if ratelimit: self._failed_login_attempts_ratelimiter.can_do_action( (medium, address) ) raise LoginError(403, "", errcode=Codes.FORBIDDEN) identifier_dict = {"type": "m.id.user", "user": user_id} # by this point, the identifier should be an m.id.user: if it's anything # else, we haven't understood it. if identifier_dict["type"] != "m.id.user": raise SynapseError(400, "Unknown login identifier type") username = identifier_dict.get("user") if not username: raise SynapseError(400, "User identifier is missing 'user' key") if username.startswith("@"): qualified_user_id = username else: qualified_user_id = UserID(username, self.hs.hostname).to_string() # Check if we've hit the failed ratelimit (but don't update it) if ratelimit: self._failed_login_attempts_ratelimiter.ratelimit( qualified_user_id.lower(), update=False ) try: return await self._validate_userid_login(username, login_submission) except LoginError: # The user has failed to log in, so we need to update the rate # limiter. Using `can_do_action` avoids us raising a ratelimit # exception and masking the LoginError. The actual ratelimiting # should have happened above. if ratelimit: self._failed_login_attempts_ratelimiter.can_do_action( qualified_user_id.lower() ) raise async def _validate_userid_login( self, username: str, login_submission: Dict[str, Any], ) -> Tuple[str, Optional[Callable[[Dict[str, str]], Awaitable[None]]]]: """Helper for validate_login Handles login, once we've mapped 3pids onto userids Args: username: the username, from the identifier dict login_submission: the whole of the login submission (including 'type' and other relevant fields) Returns: A tuple of the canonical user id, and optional callback to be called once the access token and device id are issued Raises: StoreError if there was a problem accessing the database SynapseError if there was a problem with the request LoginError if there was an authentication problem. """ if username.startswith("@"): qualified_user_id = username else: qualified_user_id = UserID(username, self.hs.hostname).to_string() login_type = login_submission.get("type") # we already checked that we have a valid login type assert isinstance(login_type, str) known_login_type = False for provider in self.password_providers: supported_login_types = provider.get_supported_login_types() if login_type not in supported_login_types: # this password provider doesn't understand this login type continue known_login_type = True login_fields = supported_login_types[login_type] missing_fields = [] login_dict = {} for f in login_fields: if f not in login_submission: missing_fields.append(f) else: login_dict[f] = login_submission[f] if missing_fields: raise SynapseError( 400, "Missing parameters for login type %s: %s" % (login_type, missing_fields), ) result = await provider.check_auth(username, login_type, login_dict) if result: return result if login_type == LoginType.PASSWORD and self._password_localdb_enabled: known_login_type = True # we've already checked that there is a (valid) password field password = login_submission["password"] assert isinstance(password, str) canonical_user_id = await self._check_local_password( qualified_user_id, password ) if canonical_user_id: return canonical_user_id, None if not known_login_type: raise SynapseError(400, "Unknown login type %s" % login_type) # We raise a 403 here, but note that if we're doing user-interactive # login, it turns all LoginErrors into a 401 anyway. raise LoginError(403, "Invalid password", errcode=Codes.FORBIDDEN) async def check_password_provider_3pid( self, medium: str, address: str, password: str ) -> Tuple[Optional[str], Optional[Callable[[Dict[str, str]], Awaitable[None]]]]: """Check if a password provider is able to validate a thirdparty login Args: medium: The medium of the 3pid (ex. email). address: The address of the 3pid (ex. jdoe@example.com). password: The password of the user. Returns: A tuple of `(user_id, callback)`. If authentication is successful, `user_id`is the authenticated, canonical user ID. `callback` is then either a function to be later run after the server has completed login/registration, or `None`. If authentication was unsuccessful, `user_id` and `callback` are both `None`. """ for provider in self.password_providers: result = await provider.check_3pid_auth(medium, address, password) if result: return result return None, None async def _check_local_password(self, user_id: str, password: str) -> Optional[str]: """Authenticate a user against the local password database. user_id is checked case insensitively, but will return None if there are multiple inexact matches. Args: user_id: complete @user:id password: the provided password Returns: The canonical_user_id, or None if unknown user/bad password """ lookupres = await self._find_user_id_and_pwd_hash(user_id) if not lookupres: return None (user_id, password_hash) = lookupres # If the password hash is None, the account has likely been deactivated if not password_hash: deactivated = await self.store.get_user_deactivated_status(user_id) if deactivated: raise UserDeactivatedError("This account has been deactivated") result = await self.validate_hash(password, password_hash) if not result: logger.warning("Failed password login for user %s", user_id) return None return user_id async def validate_short_term_login_token_and_get_user_id(self, login_token: str): auth_api = self.hs.get_auth() user_id = None try: macaroon = pymacaroons.Macaroon.deserialize(login_token) user_id = auth_api.get_user_id_from_macaroon(macaroon) auth_api.validate_macaroon(macaroon, "login", user_id) except Exception: raise AuthError(403, "Invalid token", errcode=Codes.FORBIDDEN) await self.auth.check_auth_blocking(user_id) return user_id async def delete_access_token(self, access_token: str): """Invalidate a single access token Args: access_token: access token to be deleted """ user_info = await self.auth.get_user_by_access_token(access_token) await self.store.delete_access_token(access_token) # see if any of our auth providers want to know about this for provider in self.password_providers: await provider.on_logged_out( user_id=user_info.user_id, device_id=user_info.device_id, access_token=access_token, ) # delete pushers associated with this access token if user_info.token_id is not None: await self.hs.get_pusherpool().remove_pushers_by_access_token( user_info.user_id, (user_info.token_id,) ) async def delete_access_tokens_for_user( self, user_id: str, except_token_id: Optional[str] = None, device_id: Optional[str] = None, ): """Invalidate access tokens belonging to a user Args: user_id: ID of user the tokens belong to except_token_id: access_token ID which should *not* be deleted device_id: ID of device the tokens are associated with. If None, tokens associated with any device (or no device) will be deleted """ tokens_and_devices = await self.store.user_delete_access_tokens( user_id, except_token_id=except_token_id, device_id=device_id ) # see if any of our auth providers want to know about this for provider in self.password_providers: for token, token_id, device_id in tokens_and_devices: await provider.on_logged_out( user_id=user_id, device_id=device_id, access_token=token ) # delete pushers associated with the access tokens await self.hs.get_pusherpool().remove_pushers_by_access_token( user_id, (token_id for _, token_id, _ in tokens_and_devices) ) async def add_threepid( self, user_id: str, medium: str, address: str, validated_at: int ): # check if medium has a valid value if medium not in ["email", "msisdn"]: raise SynapseError( code=400, msg=("'%s' is not a valid value for 'medium'" % (medium,)), errcode=Codes.INVALID_PARAM, ) # 'Canonicalise' email addresses down to lower case. # We've now moving towards the homeserver being the entity that # is responsible for validating threepids used for resetting passwords # on accounts, so in future Synapse will gain knowledge of specific # types (mediums) of threepid. For now, we still use the existing # infrastructure, but this is the start of synapse gaining knowledge # of specific types of threepid (and fixes the fact that checking # for the presence of an email address during password reset was # case sensitive). if medium == "email": address = canonicalise_email(address) await self.store.user_add_threepid( user_id, medium, address, validated_at, self.hs.get_clock().time_msec() ) async def delete_threepid( self, user_id: str, medium: str, address: str, id_server: Optional[str] = None ) -> bool: """Attempts to unbind the 3pid on the identity servers and deletes it from the local database. Args: user_id: ID of user to remove the 3pid from. medium: The medium of the 3pid being removed: "email" or "msisdn". address: The 3pid address to remove. id_server: Use the given identity server when unbinding any threepids. If None then will attempt to unbind using the identity server specified when binding (if known). Returns: Returns True if successfully unbound the 3pid on the identity server, False if identity server doesn't support the unbind API. """ # 'Canonicalise' email addresses as per above if medium == "email": address = canonicalise_email(address) identity_handler = self.hs.get_identity_handler() result = await identity_handler.try_unbind_threepid( user_id, {"medium": medium, "address": address, "id_server": id_server} ) await self.store.user_delete_threepid(user_id, medium, address) return result async def hash(self, password: str) -> str: """Computes a secure hash of password. Args: password: Password to hash. Returns: Hashed password. """ def _do_hash(): # Normalise the Unicode in the password pw = unicodedata.normalize("NFKC", password) return bcrypt.hashpw( pw.encode("utf8") + self.hs.config.password_pepper.encode("utf8"), bcrypt.gensalt(self.bcrypt_rounds), ).decode("ascii") return await defer_to_thread(self.hs.get_reactor(), _do_hash) async def validate_hash( self, password: str, stored_hash: Union[bytes, str] ) -> bool: """Validates that self.hash(password) == stored_hash. Args: password: Password to hash. stored_hash: Expected hash value. Returns: Whether self.hash(password) == stored_hash. """ def _do_validate_hash(checked_hash: bytes): # Normalise the Unicode in the password pw = unicodedata.normalize("NFKC", password) return bcrypt.checkpw( pw.encode("utf8") + self.hs.config.password_pepper.encode("utf8"), checked_hash, ) if stored_hash: if not isinstance(stored_hash, bytes): stored_hash = stored_hash.encode("ascii") return await defer_to_thread( self.hs.get_reactor(), _do_validate_hash, stored_hash ) else: return False async def start_sso_ui_auth(self, redirect_url: str, session_id: str) -> str: """ Get the HTML for the SSO redirect confirmation page. Args: redirect_url: The URL to redirect to the SSO provider. session_id: The user interactive authentication session ID. Returns: The HTML to render. """ try: session = await self.store.get_ui_auth_session(session_id) except StoreError: raise SynapseError(400, "Unknown session ID: %s" % (session_id,)) return self._sso_auth_confirm_template.render( description=session.description, redirect_url=redirect_url, ) async def complete_sso_ui_auth( self, registered_user_id: str, session_id: str, request: Request, ): """Having figured out a mxid for this user, complete the HTTP request Args: registered_user_id: The registered user ID to complete SSO login for. session_id: The ID of the user-interactive auth session. request: The request to complete. """ # Mark the stage of the authentication as successful. # Save the user who authenticated with SSO, this will be used to ensure # that the account be modified is also the person who logged in. await self.store.mark_ui_auth_stage_complete( session_id, LoginType.SSO, registered_user_id ) # Render the HTML and return. html = self._sso_auth_success_template respond_with_html(request, 200, html) async def complete_sso_login( self, registered_user_id: str, request: Request, client_redirect_url: str, extra_attributes: Optional[JsonDict] = None, ): """Having figured out a mxid for this user, complete the HTTP request Args: registered_user_id: The registered user ID to complete SSO login for. request: The request to complete. client_redirect_url: The URL to which to redirect the user at the end of the process. extra_attributes: Extra attributes which will be passed to the client during successful login. Must be JSON serializable. """ # If the account has been deactivated, do not proceed with the login # flow. deactivated = await self.store.get_user_deactivated_status(registered_user_id) if deactivated: respond_with_html(request, 403, self._sso_account_deactivated_template) return self._complete_sso_login( registered_user_id, request, client_redirect_url, extra_attributes ) def _complete_sso_login( self, registered_user_id: str, request: Request, client_redirect_url: str, extra_attributes: Optional[JsonDict] = None, ): """ The synchronous portion of complete_sso_login. This exists purely for backwards compatibility of synapse.module_api.ModuleApi. """ # Store any extra attributes which will be passed in the login response. # Note that this is per-user so it may overwrite a previous value, this # is considered OK since the newest SSO attributes should be most valid. if extra_attributes: self._extra_attributes[registered_user_id] = SsoLoginExtraAttributes( self._clock.time_msec(), extra_attributes, ) # Create a login token login_token = self.macaroon_gen.generate_short_term_login_token( registered_user_id ) # Append the login token to the original redirect URL (i.e. with its query # parameters kept intact) to build the URL to which the template needs to # redirect the users once they have clicked on the confirmation link. redirect_url = self.add_query_param_to_url( client_redirect_url, "loginToken", login_token ) # if the client is whitelisted, we can redirect straight to it if client_redirect_url.startswith(self._whitelisted_sso_clients): request.redirect(redirect_url) finish_request(request) return # Otherwise, serve the redirect confirmation page. # Remove the query parameters from the redirect URL to get a shorter version of # it. This is only to display a human-readable URL in the template, but not the # URL we redirect users to. redirect_url_no_params = client_redirect_url.split("?")[0] html = self._sso_redirect_confirm_template.render( display_url=redirect_url_no_params, redirect_url=redirect_url, server_name=self._server_name, ) respond_with_html(request, 200, html) async def _sso_login_callback(self, login_result: JsonDict) -> None: """ A login callback which might add additional attributes to the login response. Args: login_result: The data to be sent to the client. Includes the user ID and access token. """ # Expire attributes before processing. Note that there shouldn't be any # valid logins that still have extra attributes. self._expire_sso_extra_attributes() extra_attributes = self._extra_attributes.get(login_result["user_id"]) if extra_attributes: login_result.update(extra_attributes.extra_attributes) def _expire_sso_extra_attributes(self) -> None: """ Iterate through the mapping of user IDs to extra attributes and remove any that are no longer valid. """ # TODO This should match the amount of time the macaroon is valid for. LOGIN_TOKEN_EXPIRATION_TIME = 2 * 60 * 1000 expire_before = self._clock.time_msec() - LOGIN_TOKEN_EXPIRATION_TIME to_expire = set() for user_id, data in self._extra_attributes.items(): if data.creation_time < expire_before: to_expire.add(user_id) for user_id in to_expire: logger.debug("Expiring extra attributes for user %s", user_id) del self._extra_attributes[user_id] @staticmethod def add_query_param_to_url(url: str, param_name: str, param: Any): url_parts = list(urllib.parse.urlparse(url)) query = dict(urllib.parse.parse_qsl(url_parts[4])) query.update({param_name: param}) url_parts[4] = urllib.parse.urlencode(query) return urllib.parse.urlunparse(url_parts) @attr.s(slots=True) class MacaroonGenerator: hs = attr.ib() def generate_access_token( self, user_id: str, extra_caveats: Optional[List[str]] = None ) -> str: extra_caveats = extra_caveats or [] macaroon = self._generate_base_macaroon(user_id) macaroon.add_first_party_caveat("type = access") # Include a nonce, to make sure that each login gets a different # access token. macaroon.add_first_party_caveat( "nonce = %s" % (stringutils.random_string_with_symbols(16),) ) for caveat in extra_caveats: macaroon.add_first_party_caveat(caveat) return macaroon.serialize() def generate_short_term_login_token( self, user_id: str, duration_in_ms: int = (2 * 60 * 1000) ) -> str: macaroon = self._generate_base_macaroon(user_id) macaroon.add_first_party_caveat("type = login") now = self.hs.get_clock().time_msec() expiry = now + duration_in_ms macaroon.add_first_party_caveat("time < %d" % (expiry,)) return macaroon.serialize() def generate_delete_pusher_token(self, user_id: str) -> str: macaroon = self._generate_base_macaroon(user_id) macaroon.add_first_party_caveat("type = delete_pusher") return macaroon.serialize() def _generate_base_macaroon(self, user_id: str) -> pymacaroons.Macaroon: macaroon = pymacaroons.Macaroon( location=self.hs.config.server_name, identifier="key", key=self.hs.config.macaroon_secret_key, ) macaroon.add_first_party_caveat("gen = 1") macaroon.add_first_party_caveat("user_id = %s" % (user_id,)) return macaroon class PasswordProvider: """Wrapper for a password auth provider module This class abstracts out all of the backwards-compatibility hacks for password providers, to provide a consistent interface. """ @classmethod def load(cls, module, config, module_api: ModuleApi) -> "PasswordProvider": try: pp = module(config=config, account_handler=module_api) except Exception as e: logger.error("Error while initializing %r: %s", module, e) raise return cls(pp, module_api) def __init__(self, pp, module_api: ModuleApi): self._pp = pp self._module_api = module_api self._supported_login_types = {} # grandfather in check_password support if hasattr(self._pp, "check_password"): self._supported_login_types[LoginType.PASSWORD] = ("password",) g = getattr(self._pp, "get_supported_login_types", None) if g: self._supported_login_types.update(g()) def __str__(self): return str(self._pp) def get_supported_login_types(self) -> Mapping[str, Iterable[str]]: """Get the login types supported by this password provider Returns a map from a login type identifier (such as m.login.password) to an iterable giving the fields which must be provided by the user in the submission to the /login API. This wrapper adds m.login.password to the list if the underlying password provider supports the check_password() api. """ return self._supported_login_types async def check_auth( self, username: str, login_type: str, login_dict: JsonDict ) -> Optional[Tuple[str, Optional[Callable]]]: """Check if the user has presented valid login credentials This wrapper also calls check_password() if the underlying password provider supports the check_password() api and the login type is m.login.password. Args: username: user id presented by the client. Either an MXID or an unqualified username. login_type: the login type being attempted - one of the types returned by get_supported_login_types() login_dict: the dictionary of login secrets passed by the client. Returns: (user_id, callback) where `user_id` is the fully-qualified mxid of the user, and `callback` is an optional callback which will be called with the result from the /login call (including access_token, device_id, etc.) """ # first grandfather in a call to check_password if login_type == LoginType.PASSWORD: g = getattr(self._pp, "check_password", None) if g: qualified_user_id = self._module_api.get_qualified_user_id(username) is_valid = await self._pp.check_password( qualified_user_id, login_dict["password"] ) if is_valid: return qualified_user_id, None g = getattr(self._pp, "check_auth", None) if not g: return None result = await g(username, login_type, login_dict) # Check if the return value is a str or a tuple if isinstance(result, str): # If it's a str, set callback function to None return result, None return result async def check_3pid_auth( self, medium: str, address: str, password: str ) -> Optional[Tuple[str, Optional[Callable]]]: g = getattr(self._pp, "check_3pid_auth", None) if not g: return None # This function is able to return a deferred that either # resolves None, meaning authentication failure, or upon # success, to a str (which is the user_id) or a tuple of # (user_id, callback_func), where callback_func should be run # after we've finished everything else result = await g(medium, address, password) # Check if the return value is a str or a tuple if isinstance(result, str): # If it's a str, set callback function to None return result, None return result async def on_logged_out( self, user_id: str, device_id: Optional[str], access_token: str ) -> None: g = getattr(self._pp, "on_logged_out", None) if not g: return # This might return an awaitable, if it does block the log out # until it completes. await maybe_awaitable( g(user_id=user_id, device_id=device_id, access_token=access_token,) )