diff --git a/changelog.d/6037.feature b/changelog.d/6037.feature
new file mode 100644
index 0000000000..85553d2da0
--- /dev/null
+++ b/changelog.d/6037.feature
@@ -0,0 +1 @@
+Make the process for mapping SAML2 users to matrix IDs more flexible.
diff --git a/changelog.d/6069.bugfix b/changelog.d/6069.bugfix
new file mode 100644
index 0000000000..a437ac41a9
--- /dev/null
+++ b/changelog.d/6069.bugfix
@@ -0,0 +1 @@
+Fix a bug which caused SAML attribute maps to be overridden by defaults.
diff --git a/changelog.d/6099.misc b/changelog.d/6099.misc
new file mode 100644
index 0000000000..8415c6759b
--- /dev/null
+++ b/changelog.d/6099.misc
@@ -0,0 +1 @@
+Remove unused parameter to get_user_id_by_threepid.
diff --git a/docs/sample_config.yaml b/docs/sample_config.yaml
index 46af6edf1f..da31728037 100644
--- a/docs/sample_config.yaml
+++ b/docs/sample_config.yaml
@@ -1174,6 +1174,32 @@ saml2_config:
#
#saml_session_lifetime: 5m
+ # The SAML attribute (after mapping via the attribute maps) to use to derive
+ # the Matrix ID from. 'uid' by default.
+ #
+ #mxid_source_attribute: displayName
+
+ # The mapping system to use for mapping the saml attribute onto a matrix ID.
+ # Options include:
+ # * 'hexencode' (which maps unpermitted characters to '=xx')
+ # * 'dotreplace' (which replaces unpermitted characters with '.').
+ # The default is 'hexencode'.
+ #
+ #mxid_mapping: dotreplace
+
+ # In previous versions of synapse, the mapping from SAML attribute to MXID was
+ # always calculated dynamically rather than stored in a table. For backwards-
+ # compatibility, we will look for user_ids matching such a pattern before
+ # creating a new account.
+ #
+ # This setting controls the SAML attribute which will be used for this
+ # backwards-compatibility lookup. Typically it should be 'uid', but if the
+ # attribute maps are changed, it may be necessary to change it.
+ #
+ # The default is 'uid'.
+ #
+ #grandfathered_mxid_source_attribute: upn
+
# Enable CAS for registration and login.
diff --git a/synapse/config/saml2_config.py b/synapse/config/saml2_config.py
index c46ac087db..ab34b41ca8 100644
--- a/synapse/config/saml2_config.py
+++ b/synapse/config/saml2_config.py
@@ -1,5 +1,6 @@
# -*- coding: utf-8 -*-
# Copyright 2018 New Vector Ltd
+# Copyright 2019 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.
@@ -12,11 +13,47 @@
# 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 re
+
from synapse.python_dependencies import DependencyException, check_requirements
+from synapse.types import (
+ map_username_to_mxid_localpart,
+ mxid_localpart_allowed_characters,
+)
+from synapse.util.module_loader import load_python_module
from ._base import Config, ConfigError
+def _dict_merge(merge_dict, into_dict):
+ """Do a deep merge of two dicts
+
+ Recursively merges `merge_dict` into `into_dict`:
+ * For keys where both `merge_dict` and `into_dict` have a dict value, the values
+ are recursively merged
+ * For all other keys, the values in `into_dict` (if any) are overwritten with
+ the value from `merge_dict`.
+
+ Args:
+ merge_dict (dict): dict to merge
+ into_dict (dict): target dict
+ """
+ for k, v in merge_dict.items():
+ if k not in into_dict:
+ into_dict[k] = v
+ continue
+
+ current_val = into_dict[k]
+
+ if isinstance(v, dict) and isinstance(current_val, dict):
+ _dict_merge(v, current_val)
+ continue
+
+ # otherwise we just overwrite
+ into_dict[k] = v
+
+
class SAML2Config(Config):
def read_config(self, config, **kwargs):
self.saml2_enabled = False
@@ -36,21 +73,40 @@ class SAML2Config(Config):
self.saml2_enabled = True
- import saml2.config
+ self.saml2_mxid_source_attribute = saml2_config.get(
+ "mxid_source_attribute", "uid"
+ )
- self.saml2_sp_config = saml2.config.SPConfig()
- self.saml2_sp_config.load(self._default_saml_config_dict())
- self.saml2_sp_config.load(saml2_config.get("sp_config", {}))
+ self.saml2_grandfathered_mxid_source_attribute = saml2_config.get(
+ "grandfathered_mxid_source_attribute", "uid"
+ )
+
+ saml2_config_dict = self._default_saml_config_dict()
+ _dict_merge(
+ merge_dict=saml2_config.get("sp_config", {}), into_dict=saml2_config_dict
+ )
config_path = saml2_config.get("config_path", None)
if config_path is not None:
- self.saml2_sp_config.load_file(config_path)
+ mod = load_python_module(config_path)
+ _dict_merge(merge_dict=mod.CONFIG, into_dict=saml2_config_dict)
+
+ import saml2.config
+
+ self.saml2_sp_config = saml2.config.SPConfig()
+ self.saml2_sp_config.load(saml2_config_dict)
# session lifetime: in milliseconds
self.saml2_session_lifetime = self.parse_duration(
saml2_config.get("saml_session_lifetime", "5m")
)
+ mapping = saml2_config.get("mxid_mapping", "hexencode")
+ try:
+ self.saml2_mxid_mapper = MXID_MAPPER_MAP[mapping]
+ except KeyError:
+ raise ConfigError("%s is not a known mxid_mapping" % (mapping,))
+
def _default_saml_config_dict(self):
import saml2
@@ -58,6 +114,13 @@ class SAML2Config(Config):
if public_baseurl is None:
raise ConfigError("saml2_config requires a public_baseurl to be set")
+ required_attributes = {"uid", self.saml2_mxid_source_attribute}
+
+ optional_attributes = {"displayName"}
+ if self.saml2_grandfathered_mxid_source_attribute:
+ optional_attributes.add(self.saml2_grandfathered_mxid_source_attribute)
+ optional_attributes -= required_attributes
+
metadata_url = public_baseurl + "_matrix/saml2/metadata.xml"
response_url = public_baseurl + "_matrix/saml2/authn_response"
return {
@@ -69,8 +132,9 @@ class SAML2Config(Config):
(response_url, saml2.BINDING_HTTP_POST)
]
},
- "required_attributes": ["uid"],
- "optional_attributes": ["mail", "surname", "givenname"],
+ "required_attributes": list(required_attributes),
+ "optional_attributes": list(optional_attributes),
+ # "name_id_format": saml2.saml.NAMEID_FORMAT_PERSISTENT,
}
},
}
@@ -146,6 +210,52 @@ class SAML2Config(Config):
# The default is 5 minutes.
#
#saml_session_lifetime: 5m
+
+ # The SAML attribute (after mapping via the attribute maps) to use to derive
+ # the Matrix ID from. 'uid' by default.
+ #
+ #mxid_source_attribute: displayName
+
+ # The mapping system to use for mapping the saml attribute onto a matrix ID.
+ # Options include:
+ # * 'hexencode' (which maps unpermitted characters to '=xx')
+ # * 'dotreplace' (which replaces unpermitted characters with '.').
+ # The default is 'hexencode'.
+ #
+ #mxid_mapping: dotreplace
+
+ # In previous versions of synapse, the mapping from SAML attribute to MXID was
+ # always calculated dynamically rather than stored in a table. For backwards-
+ # compatibility, we will look for user_ids matching such a pattern before
+ # creating a new account.
+ #
+ # This setting controls the SAML attribute which will be used for this
+ # backwards-compatibility lookup. Typically it should be 'uid', but if the
+ # attribute maps are changed, it may be necessary to change it.
+ #
+ # The default is 'uid'.
+ #
+ #grandfathered_mxid_source_attribute: upn
""" % {
"config_dir_path": config_dir_path
}
+
+
+DOT_REPLACE_PATTERN = re.compile(
+ ("[^%s]" % (re.escape("".join(mxid_localpart_allowed_characters)),))
+)
+
+
+def dot_replace_for_mxid(username: str) -> str:
+ username = username.lower()
+ username = DOT_REPLACE_PATTERN.sub(".", username)
+
+ # regular mxids aren't allowed to start with an underscore either
+ username = re.sub("^_", "", username)
+ return username
+
+
+MXID_MAPPER_MAP = {
+ "hexencode": map_username_to_mxid_localpart,
+ "dotreplace": dot_replace_for_mxid,
+}
diff --git a/synapse/handlers/saml_handler.py b/synapse/handlers/saml_handler.py
index a1ce6929cf..cc9e6b9bd0 100644
--- a/synapse/handlers/saml_handler.py
+++ b/synapse/handlers/saml_handler.py
@@ -21,6 +21,8 @@ from saml2.client import Saml2Client
from synapse.api.errors import SynapseError
from synapse.http.servlet import parse_string
from synapse.rest.client.v1.login import SSOAuthHandler
+from synapse.types import UserID, map_username_to_mxid_localpart
+from synapse.util.async_helpers import Linearizer
logger = logging.getLogger(__name__)
@@ -29,12 +31,26 @@ class SamlHandler:
def __init__(self, hs):
self._saml_client = Saml2Client(hs.config.saml2_sp_config)
self._sso_auth_handler = SSOAuthHandler(hs)
+ self._registration_handler = hs.get_registration_handler()
+
+ self._clock = hs.get_clock()
+ self._datastore = hs.get_datastore()
+ self._hostname = hs.hostname
+ self._saml2_session_lifetime = hs.config.saml2_session_lifetime
+ self._mxid_source_attribute = hs.config.saml2_mxid_source_attribute
+ self._grandfathered_mxid_source_attribute = (
+ hs.config.saml2_grandfathered_mxid_source_attribute
+ )
+ self._mxid_mapper = hs.config.saml2_mxid_mapper
+
+ # identifier for the external_ids table
+ self._auth_provider_id = "saml"
# a map from saml session id to Saml2SessionData object
self._outstanding_requests_dict = {}
- self._clock = hs.get_clock()
- self._saml2_session_lifetime = hs.config.saml2_session_lifetime
+ # a lock on the mappings
+ self._mapping_lock = Linearizer(name="saml_mapping", clock=self._clock)
def handle_redirect_request(self, client_redirect_url):
"""Handle an incoming request to /login/sso/redirect
@@ -60,7 +76,7 @@ class SamlHandler:
# this shouldn't happen!
raise Exception("prepare_for_authenticate didn't return a Location header")
- def handle_saml_response(self, request):
+ async def handle_saml_response(self, request):
"""Handle an incoming request to /_matrix/saml2/authn_response
Args:
@@ -77,6 +93,10 @@ class SamlHandler:
# the dict.
self.expire_sessions()
+ user_id = await self._map_saml_response_to_user(resp_bytes)
+ self._sso_auth_handler.complete_sso_login(user_id, request, relay_state)
+
+ async def _map_saml_response_to_user(self, resp_bytes):
try:
saml2_auth = self._saml_client.parse_authn_request_response(
resp_bytes,
@@ -91,18 +111,88 @@ class SamlHandler:
logger.warning("SAML2 response was not signed")
raise SynapseError(400, "SAML2 response was not signed")
- if "uid" not in saml2_auth.ava:
+ logger.info("SAML2 response: %s", saml2_auth.origxml)
+ logger.info("SAML2 mapped attributes: %s", saml2_auth.ava)
+
+ try:
+ remote_user_id = saml2_auth.ava["uid"][0]
+ except KeyError:
logger.warning("SAML2 response lacks a 'uid' attestation")
raise SynapseError(400, "uid not in SAML2 response")
+ try:
+ mxid_source = saml2_auth.ava[self._mxid_source_attribute][0]
+ except KeyError:
+ logger.warning(
+ "SAML2 response lacks a '%s' attestation", self._mxid_source_attribute
+ )
+ raise SynapseError(
+ 400, "%s not in SAML2 response" % (self._mxid_source_attribute,)
+ )
+
self._outstanding_requests_dict.pop(saml2_auth.in_response_to, None)
- username = saml2_auth.ava["uid"][0]
displayName = saml2_auth.ava.get("displayName", [None])[0]
- return self._sso_auth_handler.on_successful_auth(
- username, request, relay_state, user_display_name=displayName
- )
+ with (await self._mapping_lock.queue(self._auth_provider_id)):
+ # first of all, check if we already have a mapping for this user
+ logger.info(
+ "Looking for existing mapping for user %s:%s",
+ self._auth_provider_id,
+ remote_user_id,
+ )
+ registered_user_id = await self._datastore.get_user_by_external_id(
+ self._auth_provider_id, remote_user_id
+ )
+ if registered_user_id is not None:
+ logger.info("Found existing mapping %s", registered_user_id)
+ return registered_user_id
+
+ # backwards-compatibility hack: see if there is an existing user with a
+ # suitable mapping from the uid
+ if (
+ self._grandfathered_mxid_source_attribute
+ and self._grandfathered_mxid_source_attribute in saml2_auth.ava
+ ):
+ attrval = saml2_auth.ava[self._grandfathered_mxid_source_attribute][0]
+ user_id = UserID(
+ map_username_to_mxid_localpart(attrval), self._hostname
+ ).to_string()
+ logger.info(
+ "Looking for existing account based on mapped %s %s",
+ self._grandfathered_mxid_source_attribute,
+ user_id,
+ )
+
+ users = await self._datastore.get_users_by_id_case_insensitive(user_id)
+ if users:
+ registered_user_id = list(users.keys())[0]
+ logger.info("Grandfathering mapping to %s", registered_user_id)
+ await self._datastore.record_user_external_id(
+ self._auth_provider_id, remote_user_id, registered_user_id
+ )
+ return registered_user_id
+
+ # figure out a new mxid for this user
+ base_mxid_localpart = self._mxid_mapper(mxid_source)
+
+ suffix = 0
+ while True:
+ localpart = base_mxid_localpart + (str(suffix) if suffix else "")
+ if not await self._datastore.get_users_by_id_case_insensitive(
+ UserID(localpart, self._hostname).to_string()
+ ):
+ break
+ suffix += 1
+ logger.info("Allocating mxid for new user with localpart %s", localpart)
+
+ registered_user_id = await self._registration_handler.register_user(
+ localpart=localpart, default_display_name=displayName
+ )
+ await self._datastore.record_user_external_id(
+ self._auth_provider_id, remote_user_id, registered_user_id
+ )
+ return registered_user_id
def expire_sessions(self):
expire_before = self._clock.time_msec() - self._saml2_session_lifetime
diff --git a/synapse/rest/client/v1/login.py b/synapse/rest/client/v1/login.py
index 25a1b67092..9cddbc752a 100644
--- a/synapse/rest/client/v1/login.py
+++ b/synapse/rest/client/v1/login.py
@@ -29,6 +29,7 @@ from synapse.http.servlet import (
parse_json_object_from_request,
parse_string,
)
+from synapse.http.site import SynapseRequest
from synapse.rest.client.v2_alpha._base import client_patterns
from synapse.rest.well_known import WellKnownBuilder
from synapse.types import UserID, map_username_to_mxid_localpart
@@ -507,6 +508,19 @@ class SSOAuthHandler(object):
localpart=localpart, default_display_name=user_display_name
)
+ self.complete_sso_login(registered_user_id, request, client_redirect_url)
+
+ def complete_sso_login(
+ self, registered_user_id: str, request: SynapseRequest, client_redirect_url: str
+ ):
+ """Having figured out a mxid for this user, complete the HTTP request
+
+ Args:
+ registered_user_id:
+ request:
+ client_redirect_url:
+ """
+
login_token = self._macaroon_gen.generate_short_term_login_token(
registered_user_id
)
diff --git a/synapse/storage/registration.py b/synapse/storage/registration.py
index 805411a6b2..ee5e85db84 100644
--- a/synapse/storage/registration.py
+++ b/synapse/storage/registration.py
@@ -22,6 +22,7 @@ from six import iterkeys
from six.moves import range
from twisted.internet import defer
+from twisted.internet.defer import Deferred
from synapse.api.constants import UserTypes
from synapse.api.errors import Codes, StoreError, SynapseError, ThreepidValidationError
@@ -384,6 +385,26 @@ class RegistrationWorkerStore(SQLBaseStore):
return self.runInteraction("get_users_by_id_case_insensitive", f)
+ async def get_user_by_external_id(
+ self, auth_provider: str, external_id: str
+ ) -> str:
+ """Look up a user by their external auth id
+
+ Args:
+ auth_provider: identifier for the remote auth provider
+ external_id: id on that system
+
+ Returns:
+ str|None: the mxid of the user, or None if they are not known
+ """
+ return await self._simple_select_one_onecol(
+ table="user_external_ids",
+ keyvalues={"auth_provider": auth_provider, "external_id": external_id},
+ retcol="user_id",
+ allow_none=True,
+ desc="get_user_by_external_id",
+ )
+
@defer.inlineCallbacks
def count_all_users(self):
"""Counts all users registered on the homeserver."""
@@ -495,7 +516,7 @@ class RegistrationWorkerStore(SQLBaseStore):
)
@defer.inlineCallbacks
- def get_user_id_by_threepid(self, medium, address, require_verified=False):
+ def get_user_id_by_threepid(self, medium, address):
"""Returns user id from threepid
Args:
@@ -1032,6 +1053,26 @@ class RegistrationStore(
self._invalidate_cache_and_stream(txn, self.get_user_by_id, (user_id,))
txn.call_after(self.is_guest.invalidate, (user_id,))
+ def record_user_external_id(
+ self, auth_provider: str, external_id: str, user_id: str
+ ) -> Deferred:
+ """Record a mapping from an external user id to a mxid
+
+ Args:
+ auth_provider: identifier for the remote auth provider
+ external_id: id on that system
+ user_id: complete mxid that it is mapped to
+ """
+ return self._simple_insert(
+ table="user_external_ids",
+ values={
+ "auth_provider": auth_provider,
+ "external_id": external_id,
+ "user_id": user_id,
+ },
+ desc="record_user_external_id",
+ )
+
def user_set_password_hash(self, user_id, password_hash):
"""
NB. This does *not* evict any cache because the one use for this
diff --git a/synapse/storage/schema/delta/56/user_external_ids.sql b/synapse/storage/schema/delta/56/user_external_ids.sql
new file mode 100644
index 0000000000..91390c4527
--- /dev/null
+++ b/synapse/storage/schema/delta/56/user_external_ids.sql
@@ -0,0 +1,24 @@
+/* Copyright 2019 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.
+ */
+
+/*
+ * a table which records mappings from external auth providers to mxids
+ */
+CREATE TABLE IF NOT EXISTS user_external_ids (
+ auth_provider TEXT NOT NULL,
+ external_id TEXT NOT NULL,
+ user_id TEXT NOT NULL,
+ UNIQUE (auth_provider, external_id)
+);
diff --git a/synapse/util/module_loader.py b/synapse/util/module_loader.py
index 522acd5aa8..7ff7eb1e4d 100644
--- a/synapse/util/module_loader.py
+++ b/synapse/util/module_loader.py
@@ -14,12 +14,13 @@
# limitations under the License.
import importlib
+import importlib.util
from synapse.config._base import ConfigError
def load_module(provider):
- """ Loads a module with its config
+ """ Loads a synapse module with its config
Take a dict with keys 'module' (the module name) and 'config'
(the config dict).
@@ -38,3 +39,20 @@ def load_module(provider):
raise ConfigError("Failed to parse config for %r: %r" % (provider["module"], e))
return provider_class, provider_config
+
+
+def load_python_module(location: str):
+ """Load a python module, and return a reference to its global namespace
+
+ Args:
+ location (str): path to the module
+
+ Returns:
+ python module object
+ """
+ spec = importlib.util.spec_from_file_location(location, location)
+ if spec is None:
+ raise Exception("Unable to load module at %s" % (location,))
+ mod = importlib.util.module_from_spec(spec)
+ spec.loader.exec_module(mod)
+ return mod
|
