synapse-old/synapse/handlers/auth.py

1099 lines
41 KiB
Python

# -*- coding: utf-8 -*-
# Copyright 2014 - 2016 OpenMarket Ltd
# Copyright 2017 Vector Creations Ltd
#
# 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 unicodedata
import attr
import bcrypt
import pymacaroons
from canonicaljson import json
from twisted.internet import defer
from twisted.web.client import PartialDownloadError
import synapse.util.stringutils as stringutils
from synapse.api.constants import LoginType
from synapse.api.errors import (
AuthError,
Codes,
InteractiveAuthIncompleteError,
LoginError,
StoreError,
SynapseError,
)
from synapse.api.ratelimiting import Ratelimiter
from synapse.logging.context import defer_to_thread
from synapse.module_api import ModuleApi
from synapse.types import UserID
from synapse.util.caches.expiringcache import ExpiringCache
from ._base import BaseHandler
logger = logging.getLogger(__name__)
class AuthHandler(BaseHandler):
SESSION_EXPIRE_MS = 48 * 60 * 60 * 1000
def __init__(self, hs):
"""
Args:
hs (synapse.server.HomeServer):
"""
super(AuthHandler, self).__init__(hs)
self.checkers = {
LoginType.RECAPTCHA: self._check_recaptcha,
LoginType.EMAIL_IDENTITY: self._check_email_identity,
LoginType.MSISDN: self._check_msisdn,
LoginType.DUMMY: self._check_dummy_auth,
LoginType.TERMS: self._check_terms_auth,
}
self.bcrypt_rounds = hs.config.bcrypt_rounds
# This is not a cache per se, but a store of all current sessions that
# expire after N hours
self.sessions = ExpiringCache(
cache_name="register_sessions",
clock=hs.get_clock(),
expiry_ms=self.SESSION_EXPIRE_MS,
reset_expiry_on_get=True,
)
account_handler = ModuleApi(hs, self)
self.password_providers = [
module(config=config, account_handler=account_handler)
for module, config in hs.config.password_providers
]
logger.info("Extra password_providers: %r", 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
# we keep this as a list despite the O(N^2) implication so that we can
# keep PASSWORD first and avoid confusing clients which pick the first
# type in the list. (NB that the spec doesn't require us to do so and
# clients which favour types that they don't understand over those that
# they do are technically broken)
login_types = []
if self._password_enabled:
login_types.append(LoginType.PASSWORD)
for provider in self.password_providers:
if hasattr(provider, "get_supported_login_types"):
for t in provider.get_supported_login_types().keys():
if t not in login_types:
login_types.append(t)
self._supported_login_types = login_types
self._account_ratelimiter = Ratelimiter()
self._failed_attempts_ratelimiter = Ratelimiter()
self._clock = self.hs.get_clock()
@defer.inlineCallbacks
def validate_user_via_ui_auth(self, requester, request_body, clientip):
"""
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 (Requester): The user, as given by the access token
request_body (dict): The body of the request sent by the client
clientip (str): The IP address of the client.
Returns:
defer.Deferred[dict]: the parameters for this request (which may
have been given only in a previous call).
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`
"""
# build a list of supported flows
flows = [[login_type] for login_type in self._supported_login_types]
result, params, _ = yield self.check_auth(flows, request_body, clientip)
# find the completed login type
for login_type in self._supported_login_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")
defer.returnValue(params)
@defer.inlineCallbacks
def check_auth(self, flows, clientdict, clientip, password_servlet=False):
"""
Takes a dictionary sent by the client in the login / registration
protocol and handles the User-Interactive Auth flow.
As a side effect, this function fills in the 'creds' key on the user's
session with a map, which maps each auth-type (str) to the relevant
identity authenticated by that auth-type (mostly str, but for captcha, bool).
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 (list): 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.
clientdict: The dictionary from the client root level, not the
'auth' key: this method prompts for auth if none is sent.
clientip (str): The IP address of the client.
password_servlet (bool): Whether the request originated from
PasswordRestServlet.
XXX: This is a temporary hack to distinguish between checking
for threepid validations locally (in the case of password
resets) and using the identity server (in the case of binding
a 3PID during registration). Once we start using the
homeserver for both tasks, this distinction will no longer be
necessary.
Returns:
defer.Deferred[dict, dict, str]: a deferred 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.
"""
authdict = None
sid = None
if clientdict and "auth" in clientdict:
authdict = clientdict["auth"]
del clientdict["auth"]
if "session" in authdict:
sid = authdict["session"]
session = self._get_session_info(sid)
if len(clientdict) > 0:
# 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 home server.
# Revisit: Assumimg the REST APIs do sensible validation, the data
# isn't arbintrary.
session["clientdict"] = clientdict
self._save_session(session)
elif "clientdict" in session:
clientdict = session["clientdict"]
if not authdict:
raise InteractiveAuthIncompleteError(
self._auth_dict_for_flows(flows, session)
)
if "creds" not in session:
session["creds"] = {}
creds = session["creds"]
# check auth type currently being presented
errordict = {}
if "type" in authdict:
login_type = authdict["type"]
try:
result = yield self._check_auth_dict(
authdict, clientip, password_servlet=password_servlet
)
if result:
creds[login_type] = result
self._save_session(session)
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()
for f in flows:
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),
)
defer.returnValue((creds, clientdict, session["id"]))
ret = self._auth_dict_for_flows(flows, session)
ret["completed"] = list(creds)
ret.update(errordict)
raise InteractiveAuthIncompleteError(ret)
@defer.inlineCallbacks
def add_oob_auth(self, stagetype, authdict, clientip):
"""
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)
sess = self._get_session_info(authdict["session"])
if "creds" not in sess:
sess["creds"] = {}
creds = sess["creds"]
result = yield self.checkers[stagetype](authdict, clientip)
if result:
creds[stagetype] = result
self._save_session(sess)
defer.returnValue(True)
defer.returnValue(False)
def get_session_id(self, clientdict):
"""
Gets the session ID for a client given the client dictionary
Args:
clientdict: The dictionary sent by the client in the request
Returns:
str|None: 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
def set_session_data(self, session_id, key, value):
"""
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 (string): The ID of this session as returned from check_auth
key (string): The key to store the data under
value (any): The data to store
"""
sess = self._get_session_info(session_id)
sess.setdefault("serverdict", {})[key] = value
self._save_session(sess)
def get_session_data(self, session_id, key, default=None):
"""
Retrieve data stored with set_session_data
Args:
session_id (string): The ID of this session as returned from check_auth
key (string): The key to store the data under
default (any): Value to return if the key has not been set
"""
sess = self._get_session_info(session_id)
return sess.setdefault("serverdict", {}).get(key, default)
@defer.inlineCallbacks
def _check_auth_dict(self, authdict, clientip, password_servlet=False):
"""Attempt to validate the auth dict provided by a client
Args:
authdict (object): auth dict provided by the client
clientip (str): IP address of the client
Returns:
Deferred: 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:
# XXX: Temporary workaround for having Synapse handle password resets
# See AuthHandler.check_auth for further details
res = yield checker(
authdict, clientip=clientip, password_servlet=password_servlet
)
defer.returnValue(res)
# build a v1-login-style dict out of the authdict and fall back to the
# v1 code
user_id = authdict.get("user")
if user_id is None:
raise SynapseError(400, "", Codes.MISSING_PARAM)
(canonical_id, callback) = yield self.validate_login(user_id, authdict)
defer.returnValue(canonical_id)
@defer.inlineCallbacks
def _check_recaptcha(self, authdict, clientip, **kwargs):
try:
user_response = authdict["response"]
except KeyError:
# Client tried to provide captcha but didn't give the parameter:
# bad request.
raise LoginError(
400, "Captcha response is required", errcode=Codes.CAPTCHA_NEEDED
)
logger.info(
"Submitting recaptcha response %s with remoteip %s", user_response, clientip
)
# TODO: get this from the homeserver rather than creating a new one for
# each request
try:
client = self.hs.get_simple_http_client()
resp_body = yield client.post_urlencoded_get_json(
self.hs.config.recaptcha_siteverify_api,
args={
"secret": self.hs.config.recaptcha_private_key,
"response": user_response,
"remoteip": clientip,
},
)
except PartialDownloadError as pde:
# Twisted is silly
data = pde.response
resp_body = json.loads(data)
if "success" in resp_body:
# Note that we do NOT check the hostname here: we explicitly
# intend the CAPTCHA to be presented by whatever client the
# user is using, we just care that they have completed a CAPTCHA.
logger.info(
"%s reCAPTCHA from hostname %s",
"Successful" if resp_body["success"] else "Failed",
resp_body.get("hostname"),
)
if resp_body["success"]:
defer.returnValue(True)
raise LoginError(401, "", errcode=Codes.UNAUTHORIZED)
def _check_email_identity(self, authdict, **kwargs):
return self._check_threepid("email", authdict, **kwargs)
def _check_msisdn(self, authdict, **kwargs):
return self._check_threepid("msisdn", authdict)
def _check_dummy_auth(self, authdict, **kwargs):
return defer.succeed(True)
def _check_terms_auth(self, authdict, **kwargs):
return defer.succeed(True)
@defer.inlineCallbacks
def _check_threepid(self, medium, authdict, password_servlet=False, **kwargs):
if "threepid_creds" not in authdict:
raise LoginError(400, "Missing threepid_creds", Codes.MISSING_PARAM)
threepid_creds = authdict["threepid_creds"]
identity_handler = self.hs.get_handlers().identity_handler
logger.info("Getting validated threepid. threepidcreds: %r", (threepid_creds,))
if (
not password_servlet
or self.hs.config.email_password_reset_behaviour == "remote"
):
threepid = yield identity_handler.threepid_from_creds(threepid_creds)
elif self.hs.config.email_password_reset_behaviour == "local":
row = yield self.store.get_threepid_validation_session(
medium,
threepid_creds["client_secret"],
sid=threepid_creds["sid"],
validated=True,
)
threepid = (
{
"medium": row["medium"],
"address": row["address"],
"validated_at": row["validated_at"],
}
if row
else None
)
if row:
# Valid threepid returned, delete from the db
yield self.store.delete_threepid_session(threepid_creds["sid"])
else:
raise SynapseError(
400, "Password resets are not enabled on this homeserver"
)
if not threepid:
raise LoginError(401, "", errcode=Codes.UNAUTHORIZED)
if threepid["medium"] != medium:
raise LoginError(
401,
"Expecting threepid of type '%s', got '%s'"
% (medium, threepid["medium"]),
errcode=Codes.UNAUTHORIZED,
)
threepid["threepid_creds"] = authdict["threepid_creds"]
defer.returnValue(threepid)
def _get_params_recaptcha(self):
return {"public_key": self.hs.config.recaptcha_public_key}
def _get_params_terms(self):
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, session):
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 = {}
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,
}
def _get_session_info(self, session_id):
if session_id not in self.sessions:
session_id = None
if not session_id:
# create a new session
while session_id is None or session_id in self.sessions:
session_id = stringutils.random_string(24)
self.sessions[session_id] = {"id": session_id}
return self.sessions[session_id]
@defer.inlineCallbacks
def get_access_token_for_user_id(self, user_id, device_id=None):
"""
Creates a new access token for the user with the given user ID.
The user is assumed to have been authenticated by some other
machanism (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 (str): canonical User ID
device_id (str|None): 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)
Returns:
The access token for the user's session.
Raises:
StoreError if there was a problem storing the token.
"""
logger.info("Logging in user %s on device %s", user_id, device_id)
access_token = yield self.issue_access_token(user_id, device_id)
yield self.auth.check_auth_blocking(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:
yield self.store.get_device(user_id, device_id)
except StoreError:
yield self.store.delete_access_token(access_token)
raise StoreError(400, "Login raced against device deletion")
defer.returnValue(access_token)
@defer.inlineCallbacks
def check_user_exists(self, user_id):
"""
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:
(unicode|bytes) user_id: complete @user:id
Returns:
defer.Deferred: (unicode) canonical_user_id, or None if zero or
multiple matches
Raises:
LimitExceededError if the ratelimiter's login requests count for this
user is too high too proceed.
"""
self.ratelimit_login_per_account(user_id)
res = yield self._find_user_id_and_pwd_hash(user_id)
if res is not None:
defer.returnValue(res[0])
defer.returnValue(None)
@defer.inlineCallbacks
def _find_user_id_and_pwd_hash(self, user_id):
"""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:
tuple: A 2-tuple of `(canonical_user_id, password_hash)`
None: if there is not exactly one match
"""
user_infos = yield self.store.get_users_by_id_case_insensitive(user_id)
result = None
if not user_infos:
logger.warn("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.warn(
"Attempted to login as %s but it matches more than one user "
"inexactly: %r",
user_id,
user_infos.keys(),
)
defer.returnValue(result)
def get_supported_login_types(self):
"""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:
Iterable[str]: login types
"""
return self._supported_login_types
@defer.inlineCallbacks
def validate_login(self, username, login_submission):
"""Authenticates the user for the /login API
Also used by the user-interactive auth flow to validate
m.login.password auth types.
Args:
username (str): username supplied by the user
login_submission (dict): the whole of the login submission
(including 'type' and other relevant fields)
Returns:
Deferred[str, func]: 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.
LimitExceededError if the ratelimiter's login requests count for this
user is too high too proceed.
"""
if username.startswith("@"):
qualified_user_id = username
else:
qualified_user_id = UserID(username, self.hs.hostname).to_string()
self.ratelimit_login_per_account(qualified_user_id)
login_type = login_submission.get("type")
known_login_type = False
# 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 password:
raise SynapseError(400, "Missing parameter: password")
for provider in self.password_providers:
if hasattr(provider, "check_password") and login_type == LoginType.PASSWORD:
known_login_type = True
is_valid = yield provider.check_password(qualified_user_id, password)
if is_valid:
defer.returnValue((qualified_user_id, None))
if not hasattr(provider, "get_supported_login_types") or not hasattr(
provider, "check_auth"
):
# this password provider doesn't understand custom login types
continue
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 = yield provider.check_auth(username, login_type, login_dict)
if result:
if isinstance(result, str):
result = (result, None)
defer.returnValue(result)
if login_type == LoginType.PASSWORD and self.hs.config.password_localdb_enabled:
known_login_type = True
canonical_user_id = yield self._check_local_password(
qualified_user_id, password
)
if canonical_user_id:
defer.returnValue((canonical_user_id, None))
if not known_login_type:
raise SynapseError(400, "Unknown login type %s" % login_type)
# unknown username or invalid password.
self._failed_attempts_ratelimiter.ratelimit(
qualified_user_id.lower(),
time_now_s=self._clock.time(),
rate_hz=self.hs.config.rc_login_failed_attempts.per_second,
burst_count=self.hs.config.rc_login_failed_attempts.burst_count,
update=True,
)
# 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)
@defer.inlineCallbacks
def check_password_provider_3pid(self, medium, address, password):
"""Check if a password provider is able to validate a thirdparty login
Args:
medium (str): The medium of the 3pid (ex. email).
address (str): The address of the 3pid (ex. jdoe@example.com).
password (str): The password of the user.
Returns:
Deferred[(str|None, func|None)]: A tuple of `(user_id,
callback)`. If authentication is successful, `user_id` is a `str`
containing 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:
if hasattr(provider, "check_3pid_auth"):
# 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 = yield provider.check_3pid_auth(medium, address, password)
if result:
# 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
result = (result, None)
defer.returnValue(result)
defer.returnValue((None, None))
@defer.inlineCallbacks
def _check_local_password(self, user_id, password):
"""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 (unicode): complete @user:id
password (unicode): the provided password
Returns:
Deferred[unicode] the canonical_user_id, or Deferred[None] if
unknown user/bad password
Raises:
LimitExceededError if the ratelimiter's login requests count for this
user is too high too proceed.
"""
lookupres = yield self._find_user_id_and_pwd_hash(user_id)
if not lookupres:
defer.returnValue(None)
(user_id, password_hash) = lookupres
result = yield self.validate_hash(password, password_hash)
if not result:
logger.warn("Failed password login for user %s", user_id)
defer.returnValue(None)
defer.returnValue(user_id)
@defer.inlineCallbacks
def issue_access_token(self, user_id, device_id=None):
access_token = self.macaroon_gen.generate_access_token(user_id)
yield self.store.add_access_token_to_user(user_id, access_token, device_id)
defer.returnValue(access_token)
@defer.inlineCallbacks
def validate_short_term_login_token_and_get_user_id(self, login_token):
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", True, user_id)
except Exception:
raise AuthError(403, "Invalid token", errcode=Codes.FORBIDDEN)
self.ratelimit_login_per_account(user_id)
yield self.auth.check_auth_blocking(user_id)
defer.returnValue(user_id)
@defer.inlineCallbacks
def delete_access_token(self, access_token):
"""Invalidate a single access token
Args:
access_token (str): access token to be deleted
Returns:
Deferred
"""
user_info = yield self.auth.get_user_by_access_token(access_token)
yield 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:
if hasattr(provider, "on_logged_out"):
yield provider.on_logged_out(
user_id=str(user_info["user"]),
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:
yield self.hs.get_pusherpool().remove_pushers_by_access_token(
str(user_info["user"]), (user_info["token_id"],)
)
@defer.inlineCallbacks
def delete_access_tokens_for_user(
self, user_id, except_token_id=None, device_id=None
):
"""Invalidate access tokens belonging to a user
Args:
user_id (str): ID of user the tokens belong to
except_token_id (str|None): access_token ID which should *not* be
deleted
device_id (str|None): ID of device the tokens are associated with.
If None, tokens associated with any device (or no device) will
be deleted
Returns:
Deferred
"""
tokens_and_devices = yield 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:
if hasattr(provider, "on_logged_out"):
for token, token_id, device_id in tokens_and_devices:
yield provider.on_logged_out(
user_id=user_id, device_id=device_id, access_token=token
)
# delete pushers associated with the access tokens
yield self.hs.get_pusherpool().remove_pushers_by_access_token(
user_id, (token_id for _, token_id, _ in tokens_and_devices)
)
@defer.inlineCallbacks
def add_threepid(self, user_id, medium, address, validated_at):
# 'Canonicalise' email addresses down to lower case.
# We've now moving towards the Home Server 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 = address.lower()
yield self.store.user_add_threepid(
user_id, medium, address, validated_at, self.hs.get_clock().time_msec()
)
@defer.inlineCallbacks
def delete_threepid(self, user_id, medium, address, id_server=None):
"""Attempts to unbind the 3pid on the identity servers and deletes it
from the local database.
Args:
user_id (str)
medium (str)
address (str)
id_server (str|None): 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:
Deferred[bool]: 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 = address.lower()
identity_handler = self.hs.get_handlers().identity_handler
result = yield identity_handler.try_unbind_threepid(
user_id, {"medium": medium, "address": address, "id_server": id_server}
)
yield self.store.user_delete_threepid(user_id, medium, address)
defer.returnValue(result)
def _save_session(self, session):
# TODO: Persistent storage
logger.debug("Saving session %s", session)
session["last_used"] = self.hs.get_clock().time_msec()
self.sessions[session["id"]] = session
def hash(self, password):
"""Computes a secure hash of password.
Args:
password (unicode): Password to hash.
Returns:
Deferred(unicode): 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 defer_to_thread(self.hs.get_reactor(), _do_hash)
def validate_hash(self, password, stored_hash):
"""Validates that self.hash(password) == stored_hash.
Args:
password (unicode): Password to hash.
stored_hash (bytes): Expected hash value.
Returns:
Deferred(bool): Whether self.hash(password) == stored_hash.
"""
def _do_validate_hash():
# Normalise the Unicode in the password
pw = unicodedata.normalize("NFKC", password)
return bcrypt.checkpw(
pw.encode("utf8") + self.hs.config.password_pepper.encode("utf8"),
stored_hash,
)
if stored_hash:
if not isinstance(stored_hash, bytes):
stored_hash = stored_hash.encode("ascii")
return defer_to_thread(self.hs.get_reactor(), _do_validate_hash)
else:
return defer.succeed(False)
def ratelimit_login_per_account(self, user_id):
"""Checks whether the process must be stopped because of ratelimiting.
Checks against two ratelimiters: the generic one for login attempts per
account and the one specific to failed attempts.
Args:
user_id (unicode): complete @user:id
Raises:
LimitExceededError if one of the ratelimiters' login requests count
for this user is too high too proceed.
"""
self._failed_attempts_ratelimiter.ratelimit(
user_id.lower(),
time_now_s=self._clock.time(),
rate_hz=self.hs.config.rc_login_failed_attempts.per_second,
burst_count=self.hs.config.rc_login_failed_attempts.burst_count,
update=False,
)
self._account_ratelimiter.ratelimit(
user_id.lower(),
time_now_s=self._clock.time(),
rate_hz=self.hs.config.rc_login_account.per_second,
burst_count=self.hs.config.rc_login_account.burst_count,
update=True,
)
@attr.s
class MacaroonGenerator(object):
hs = attr.ib()
def generate_access_token(self, user_id, extra_caveats=None):
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, duration_in_ms=(2 * 60 * 1000)):
"""
Args:
user_id (unicode):
duration_in_ms (int):
Returns:
unicode
"""
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):
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):
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