From 447f4f0d5f136dcadd5fdc286ded2d6e24a3f686 Mon Sep 17 00:00:00 2001 From: Matthew Hodgson Date: Fri, 19 Jan 2018 15:33:55 +0000 Subject: rewrite based on PR feedback: * [ ] split config options into allowed_local_3pids and registrations_require_3pid * [ ] simplify and comment logic for picking registration flows * [ ] fix docstring and move check_3pid_allowed into a new util module * [ ] use check_3pid_allowed everywhere @erikjohnston PTAL --- synapse/util/threepids.py | 45 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 45 insertions(+) create mode 100644 synapse/util/threepids.py (limited to 'synapse/util') diff --git a/synapse/util/threepids.py b/synapse/util/threepids.py new file mode 100644 index 0000000000..e921b97796 --- /dev/null +++ b/synapse/util/threepids.py @@ -0,0 +1,45 @@ +# -*- coding: utf-8 -*- +# Copyright 2018 New Vector 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 re + +logger = logging.getLogger(__name__) + + +def check_3pid_allowed(hs, medium, address): + """Checks whether a given format of 3PID is allowed to be used on this HS + + Args: + hs (synapse.server.HomeServer): server + medium (str): 3pid medium - e.g. email, msisdn + address (str): address within that medium (e.g. "wotan@matrix.org") + msisdns need to first have been canonicalised + """ + + if hs.config.allowed_local_3pids: + for constraint in hs.config.allowed_local_3pids: + logger.debug("Checking 3PID %s (%s) against %s (%s)" % ( + address, medium, constraint['pattern'], constraint['medium'] + )) + if ( + medium == constraint['medium'] and + re.match(constraint['pattern'], address) + ): + return True + else: + return True + + return False -- cgit 1.5.1 From 8fe253f19b1c61c38111948cce00a7d260d2925a Mon Sep 17 00:00:00 2001 From: Matthew Hodgson Date: Fri, 19 Jan 2018 18:23:45 +0000 Subject: fix PR nitpicking --- synapse/util/threepids.py | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) (limited to 'synapse/util') diff --git a/synapse/util/threepids.py b/synapse/util/threepids.py index e921b97796..75efa0117b 100644 --- a/synapse/util/threepids.py +++ b/synapse/util/threepids.py @@ -27,13 +27,16 @@ def check_3pid_allowed(hs, medium, address): medium (str): 3pid medium - e.g. email, msisdn address (str): address within that medium (e.g. "wotan@matrix.org") msisdns need to first have been canonicalised + Returns: + bool: whether the 3PID medium/address is allowed to be added to this HS """ if hs.config.allowed_local_3pids: for constraint in hs.config.allowed_local_3pids: - logger.debug("Checking 3PID %s (%s) against %s (%s)" % ( - address, medium, constraint['pattern'], constraint['medium'] - )) + logger.debug( + "Checking 3PID %s (%s) against %s (%s)", + address, medium, constraint['pattern'], constraint['medium'], + ) if ( medium == constraint['medium'] and re.match(constraint['pattern'], address) -- cgit 1.5.1 From ab9f844aaf3662a64dbc4c56077e9fa37bc7d5d0 Mon Sep 17 00:00:00 2001 From: Matthew Hodgson Date: Mon, 22 Jan 2018 19:11:18 +0100 Subject: Add federation_domain_whitelist option (#2820) Add federation_domain_whitelist gives a way to restrict which domains your HS is allowed to federate with. useful mainly for gracefully preventing a private but internet-connected HS from trying to federate to the wider public Matrix network --- synapse/api/errors.py | 26 ++++++++++++++++++++++++++ synapse/config/server.py | 22 ++++++++++++++++++++++ synapse/federation/federation_client.py | 5 ++++- synapse/federation/transaction_queue.py | 4 +++- synapse/federation/transport/client.py | 3 +++ synapse/federation/transport/server.py | 9 ++++++++- synapse/handlers/device.py | 4 ++++ synapse/handlers/e2e_keys.py | 8 +++++++- synapse/handlers/federation.py | 4 ++++ synapse/http/matrixfederationclient.py | 28 +++++++++++++++++++++++++++- synapse/rest/key/v2/remote_key_resource.py | 8 ++++++++ synapse/rest/media/v1/media_repository.py | 19 +++++++++++++++++-- synapse/util/retryutils.py | 12 ++++++++++++ tests/utils.py | 1 + 14 files changed, 146 insertions(+), 7 deletions(-) (limited to 'synapse/util') diff --git a/synapse/api/errors.py b/synapse/api/errors.py index 46b0d7b34c..aa15f73f36 100644 --- a/synapse/api/errors.py +++ b/synapse/api/errors.py @@ -141,6 +141,32 @@ class RegistrationError(SynapseError): pass +class FederationDeniedError(SynapseError): + """An error raised when the server tries to federate with a server which + is not on its federation whitelist. + + Attributes: + destination (str): The destination which has been denied + """ + + def __init__(self, destination): + """Raised by federation client or server to indicate that we are + are deliberately not attempting to contact a given server because it is + not on our federation whitelist. + + Args: + destination (str): the domain in question + """ + + self.destination = destination + + super(FederationDeniedError, self).__init__( + code=403, + msg="Federation denied with %s." % (self.destination,), + errcode=Codes.FORBIDDEN, + ) + + class InteractiveAuthIncompleteError(Exception): """An error raised when UI auth is not yet complete diff --git a/synapse/config/server.py b/synapse/config/server.py index 436dd8a6fe..8f0b6d1f28 100644 --- a/synapse/config/server.py +++ b/synapse/config/server.py @@ -55,6 +55,17 @@ class ServerConfig(Config): "block_non_admin_invites", False, ) + # FIXME: federation_domain_whitelist needs sytests + self.federation_domain_whitelist = None + federation_domain_whitelist = config.get( + "federation_domain_whitelist", None + ) + # turn the whitelist into a hash for speed of lookup + if federation_domain_whitelist is not None: + self.federation_domain_whitelist = {} + for domain in federation_domain_whitelist: + self.federation_domain_whitelist[domain] = True + if self.public_baseurl is not None: if self.public_baseurl[-1] != '/': self.public_baseurl += '/' @@ -210,6 +221,17 @@ class ServerConfig(Config): # (except those sent by local server admins). The default is False. # block_non_admin_invites: True + # Restrict federation to the following whitelist of domains. + # N.B. we recommend also firewalling your federation listener to limit + # inbound federation traffic as early as possible, rather than relying + # purely on this application-layer restriction. If not specified, the + # default is to whitelist everything. + # + # federation_domain_whitelist: + # - lon.example.com + # - nyc.example.com + # - syd.example.com + # List of ports that Synapse should listen on, their purpose and their # configuration. listeners: diff --git a/synapse/federation/federation_client.py b/synapse/federation/federation_client.py index b1fe03f702..813907f7f2 100644 --- a/synapse/federation/federation_client.py +++ b/synapse/federation/federation_client.py @@ -23,7 +23,7 @@ from twisted.internet import defer from synapse.api.constants import Membership from synapse.api.errors import ( - CodeMessageException, HttpResponseException, SynapseError, + CodeMessageException, HttpResponseException, SynapseError, FederationDeniedError ) from synapse.events import builder from synapse.federation.federation_base import ( @@ -266,6 +266,9 @@ class FederationClient(FederationBase): except NotRetryingDestination as e: logger.info(e.message) continue + except FederationDeniedError as e: + logger.info(e.message) + continue except Exception as e: pdu_attempts[destination] = now diff --git a/synapse/federation/transaction_queue.py b/synapse/federation/transaction_queue.py index 9d39f46583..a141ec9953 100644 --- a/synapse/federation/transaction_queue.py +++ b/synapse/federation/transaction_queue.py @@ -19,7 +19,7 @@ from twisted.internet import defer from .persistence import TransactionActions from .units import Transaction, Edu -from synapse.api.errors import HttpResponseException +from synapse.api.errors import HttpResponseException, FederationDeniedError from synapse.util import logcontext, PreserveLoggingContext from synapse.util.async import run_on_reactor from synapse.util.retryutils import NotRetryingDestination, get_retry_limiter @@ -490,6 +490,8 @@ class TransactionQueue(object): (e.retry_last_ts + e.retry_interval) / 1000.0 ), ) + except FederationDeniedError as e: + logger.info(e) except Exception as e: logger.warn( "TX [%s] Failed to send transaction: %s", diff --git a/synapse/federation/transport/client.py b/synapse/federation/transport/client.py index 1f3ce238f6..5488e82985 100644 --- a/synapse/federation/transport/client.py +++ b/synapse/federation/transport/client.py @@ -212,6 +212,9 @@ class TransportLayerClient(object): Fails with ``NotRetryingDestination`` if we are not yet ready to retry this server. + + Fails with ``FederationDeniedError`` if the remote destination + is not in our federation whitelist """ valid_memberships = {Membership.JOIN, Membership.LEAVE} if membership not in valid_memberships: diff --git a/synapse/federation/transport/server.py b/synapse/federation/transport/server.py index 2b02b021ec..06c16ba4fa 100644 --- a/synapse/federation/transport/server.py +++ b/synapse/federation/transport/server.py @@ -16,7 +16,7 @@ from twisted.internet import defer from synapse.api.urls import FEDERATION_PREFIX as PREFIX -from synapse.api.errors import Codes, SynapseError +from synapse.api.errors import Codes, SynapseError, FederationDeniedError from synapse.http.server import JsonResource from synapse.http.servlet import ( parse_json_object_from_request, parse_integer_from_args, parse_string_from_args, @@ -81,6 +81,7 @@ class Authenticator(object): self.keyring = hs.get_keyring() self.server_name = hs.hostname self.store = hs.get_datastore() + self.federation_domain_whitelist = hs.config.federation_domain_whitelist # A method just so we can pass 'self' as the authenticator to the Servlets @defer.inlineCallbacks @@ -92,6 +93,12 @@ class Authenticator(object): "signatures": {}, } + if ( + self.federation_domain_whitelist is not None and + self.server_name not in self.federation_domain_whitelist + ): + raise FederationDeniedError(self.server_name) + if content is not None: json_request["content"] = content diff --git a/synapse/handlers/device.py b/synapse/handlers/device.py index 2152efc692..0e83453851 100644 --- a/synapse/handlers/device.py +++ b/synapse/handlers/device.py @@ -14,6 +14,7 @@ # limitations under the License. from synapse.api import errors from synapse.api.constants import EventTypes +from synapse.api.errors import FederationDeniedError from synapse.util import stringutils from synapse.util.async import Linearizer from synapse.util.caches.expiringcache import ExpiringCache @@ -513,6 +514,9 @@ class DeviceListEduUpdater(object): # This makes it more likely that the device lists will # eventually become consistent. return + except FederationDeniedError as e: + logger.info(e) + return except Exception: # TODO: Remember that we are now out of sync and try again # later diff --git a/synapse/handlers/e2e_keys.py b/synapse/handlers/e2e_keys.py index 5af8abf66b..9aa95f89e6 100644 --- a/synapse/handlers/e2e_keys.py +++ b/synapse/handlers/e2e_keys.py @@ -19,7 +19,9 @@ import logging from canonicaljson import encode_canonical_json from twisted.internet import defer -from synapse.api.errors import SynapseError, CodeMessageException +from synapse.api.errors import ( + SynapseError, CodeMessageException, FederationDeniedError, +) from synapse.types import get_domain_from_id, UserID from synapse.util.logcontext import preserve_fn, make_deferred_yieldable from synapse.util.retryutils import NotRetryingDestination @@ -140,6 +142,10 @@ class E2eKeysHandler(object): failures[destination] = { "status": 503, "message": "Not ready for retry", } + except FederationDeniedError as e: + failures[destination] = { + "status": 403, "message": "Federation Denied", + } except Exception as e: # include ConnectionRefused and other errors failures[destination] = { diff --git a/synapse/handlers/federation.py b/synapse/handlers/federation.py index ac70730885..677532c87b 100644 --- a/synapse/handlers/federation.py +++ b/synapse/handlers/federation.py @@ -22,6 +22,7 @@ from ._base import BaseHandler from synapse.api.errors import ( AuthError, FederationError, StoreError, CodeMessageException, SynapseError, + FederationDeniedError, ) from synapse.api.constants import EventTypes, Membership, RejectedReason from synapse.events.validator import EventValidator @@ -782,6 +783,9 @@ class FederationHandler(BaseHandler): except NotRetryingDestination as e: logger.info(e.message) continue + except FederationDeniedError as e: + logger.info(e) + continue except Exception as e: logger.exception( "Failed to backfill from %s because %s", diff --git a/synapse/http/matrixfederationclient.py b/synapse/http/matrixfederationclient.py index 833496b72d..9145405cb0 100644 --- a/synapse/http/matrixfederationclient.py +++ b/synapse/http/matrixfederationclient.py @@ -27,7 +27,7 @@ import synapse.metrics from canonicaljson import encode_canonical_json from synapse.api.errors import ( - SynapseError, Codes, HttpResponseException, + SynapseError, Codes, HttpResponseException, FederationDeniedError, ) from signedjson.sign import sign_json @@ -123,11 +123,22 @@ class MatrixFederationHttpClient(object): Fails with ``HTTPRequestException``: if we get an HTTP response code >= 300. + Fails with ``NotRetryingDestination`` if we are not yet ready to retry this server. + + Fails with ``FederationDeniedError`` if this destination + is not on our federation whitelist + (May also fail with plenty of other Exceptions for things like DNS failures, connection failures, SSL failures.) """ + if ( + self.hs.config.federation_domain_whitelist and + destination not in self.hs.config.federation_domain_whitelist + ): + raise FederationDeniedError(destination) + limiter = yield synapse.util.retryutils.get_retry_limiter( destination, self.clock, @@ -308,6 +319,9 @@ class MatrixFederationHttpClient(object): Fails with ``NotRetryingDestination`` if we are not yet ready to retry this server. + + Fails with ``FederationDeniedError`` if this destination + is not on our federation whitelist """ if not json_data_callback: @@ -368,6 +382,9 @@ class MatrixFederationHttpClient(object): Fails with ``NotRetryingDestination`` if we are not yet ready to retry this server. + + Fails with ``FederationDeniedError`` if this destination + is not on our federation whitelist """ def body_callback(method, url_bytes, headers_dict): @@ -422,6 +439,9 @@ class MatrixFederationHttpClient(object): Fails with ``NotRetryingDestination`` if we are not yet ready to retry this server. + + Fails with ``FederationDeniedError`` if this destination + is not on our federation whitelist """ logger.debug("get_json args: %s", args) @@ -475,6 +495,9 @@ class MatrixFederationHttpClient(object): Fails with ``NotRetryingDestination`` if we are not yet ready to retry this server. + + Fails with ``FederationDeniedError`` if this destination + is not on our federation whitelist """ response = yield self._request( @@ -518,6 +541,9 @@ class MatrixFederationHttpClient(object): Fails with ``NotRetryingDestination`` if we are not yet ready to retry this server. + + Fails with ``FederationDeniedError`` if this destination + is not on our federation whitelist """ encoded_args = {} diff --git a/synapse/rest/key/v2/remote_key_resource.py b/synapse/rest/key/v2/remote_key_resource.py index cc2842aa72..17e6079cba 100644 --- a/synapse/rest/key/v2/remote_key_resource.py +++ b/synapse/rest/key/v2/remote_key_resource.py @@ -93,6 +93,7 @@ class RemoteKey(Resource): self.store = hs.get_datastore() self.version_string = hs.version_string self.clock = hs.get_clock() + self.federation_domain_whitelist = hs.config.federation_domain_whitelist def render_GET(self, request): self.async_render_GET(request) @@ -137,6 +138,13 @@ class RemoteKey(Resource): logger.info("Handling query for keys %r", query) store_queries = [] for server_name, key_ids in query.items(): + if ( + self.federation_domain_whitelist is not None and + server_name not in self.federation_domain_whitelist + ): + logger.debug("Federation denied with %s", server_name) + continue + if not key_ids: key_ids = (None,) for key_id in key_ids: diff --git a/synapse/rest/media/v1/media_repository.py b/synapse/rest/media/v1/media_repository.py index 4f56bcf577..485db8577a 100644 --- a/synapse/rest/media/v1/media_repository.py +++ b/synapse/rest/media/v1/media_repository.py @@ -32,8 +32,9 @@ from .media_storage import MediaStorage from synapse.http.matrixfederationclient import MatrixFederationHttpClient from synapse.util.stringutils import random_string -from synapse.api.errors import SynapseError, HttpResponseException, \ - NotFoundError +from synapse.api.errors import ( + SynapseError, HttpResponseException, NotFoundError, FederationDeniedError, +) from synapse.util.async import Linearizer from synapse.util.stringutils import is_ascii @@ -75,6 +76,8 @@ class MediaRepository(object): self.recently_accessed_remotes = set() self.recently_accessed_locals = set() + self.federation_domain_whitelist = hs.config.federation_domain_whitelist + # List of StorageProviders where we should search for media and # potentially upload to. storage_providers = [] @@ -216,6 +219,12 @@ class MediaRepository(object): Deferred: Resolves once a response has successfully been written to request """ + if ( + self.federation_domain_whitelist is not None and + server_name not in self.federation_domain_whitelist + ): + raise FederationDeniedError(server_name) + self.mark_recently_accessed(server_name, media_id) # We linearize here to ensure that we don't try and download remote @@ -250,6 +259,12 @@ class MediaRepository(object): Returns: Deferred[dict]: The media_info of the file """ + if ( + self.federation_domain_whitelist is not None and + server_name not in self.federation_domain_whitelist + ): + raise FederationDeniedError(server_name) + # We linearize here to ensure that we don't try and download remote # media multiple times concurrently key = (server_name, media_id) diff --git a/synapse/util/retryutils.py b/synapse/util/retryutils.py index 1adedbb361..47b0bb5eb3 100644 --- a/synapse/util/retryutils.py +++ b/synapse/util/retryutils.py @@ -26,6 +26,18 @@ logger = logging.getLogger(__name__) class NotRetryingDestination(Exception): def __init__(self, retry_last_ts, retry_interval, destination): + """Raised by the limiter (and federation client) to indicate that we are + are deliberately not attempting to contact a given server. + + Args: + retry_last_ts (int): the unix ts in milliseconds of our last attempt + to contact the server. 0 indicates that the last attempt was + successful or that we've never actually attempted to connect. + retry_interval (int): the time in milliseconds to wait until the next + attempt. + destination (str): the domain in question + """ + msg = "Not retrying server %s." % (destination,) super(NotRetryingDestination, self).__init__(msg) diff --git a/tests/utils.py b/tests/utils.py index 44e5f75093..3116047892 100644 --- a/tests/utils.py +++ b/tests/utils.py @@ -57,6 +57,7 @@ def setup_test_homeserver(name="test", datastore=None, config=None, **kargs): config.worker_app = None config.email_enable_notifs = False config.block_non_admin_invites = False + config.federation_domain_whitelist = None # disable user directory updates, because they get done in the # background, which upsets the test runner. -- cgit 1.5.1