From 47815edcfae73c5b938f8354853a09c0b80ef27e Mon Sep 17 00:00:00 2001 From: Richard van der Hoff Date: Fri, 11 May 2018 00:17:11 +0100 Subject: [PATCH] ConsentResource to gather policy consent from users Hopefully there are enough comments and docs in this that it makes sense on its own. --- docs/privacy_policy_templates/README.md | 23 ++ docs/privacy_policy_templates/en/1.0.html | 17 ++ docs/privacy_policy_templates/en/success.html | 11 + synapse/app/homeserver.py | 9 + synapse/config/__init__.py | 6 + synapse/config/consent_config.py | 42 ++++ synapse/config/homeserver.py | 8 +- synapse/config/key.py | 10 + synapse/http/server.py | 76 ++++++- synapse/rest/consent/__init__.py | 0 synapse/rest/consent/consent_resource.py | 210 ++++++++++++++++++ synapse/server.py | 3 + synapse/storage/registration.py | 18 ++ .../schema/delta/48/add_user_consent.sql | 18 ++ 14 files changed, 446 insertions(+), 5 deletions(-) create mode 100644 docs/privacy_policy_templates/README.md create mode 100644 docs/privacy_policy_templates/en/1.0.html create mode 100644 docs/privacy_policy_templates/en/success.html create mode 100644 synapse/config/consent_config.py create mode 100644 synapse/rest/consent/__init__.py create mode 100644 synapse/rest/consent/consent_resource.py create mode 100644 synapse/storage/schema/delta/48/add_user_consent.sql diff --git a/docs/privacy_policy_templates/README.md b/docs/privacy_policy_templates/README.md new file mode 100644 index 000000000..8e91c516b --- /dev/null +++ b/docs/privacy_policy_templates/README.md @@ -0,0 +1,23 @@ +If enabling the 'consent' resource in synapse, you will need some templates +for the HTML to be served to the user. This directory contains very simple +examples of the sort of thing that can be done. + +You'll need to add this sort of thing to your homeserver.yaml: + +``` +form_secret: + +user_consent: + template_dir: docs/privacy_policy_templates + default_version: 1.0 +``` + +You should then be able to enable the `consent` resource under a `listener` +entry. For example: + +``` +listeners: + - port: 8008 + resources: + - names: [client, consent] +``` diff --git a/docs/privacy_policy_templates/en/1.0.html b/docs/privacy_policy_templates/en/1.0.html new file mode 100644 index 000000000..ab8666f0c --- /dev/null +++ b/docs/privacy_policy_templates/en/1.0.html @@ -0,0 +1,17 @@ + + + + Matrix.org Privacy policy + + +

+ All your base are belong to us. +

+
+ + + + +
+ + diff --git a/docs/privacy_policy_templates/en/success.html b/docs/privacy_policy_templates/en/success.html new file mode 100644 index 000000000..d55e90c94 --- /dev/null +++ b/docs/privacy_policy_templates/en/success.html @@ -0,0 +1,11 @@ + + + + Matrix.org Privacy policy + + +

+ Sweet. +

+ + diff --git a/synapse/app/homeserver.py b/synapse/app/homeserver.py index a0e465d64..730271628 100755 --- a/synapse/app/homeserver.py +++ b/synapse/app/homeserver.py @@ -41,6 +41,7 @@ from synapse.python_dependencies import CONDITIONAL_REQUIREMENTS, \ from synapse.replication.http import ReplicationRestResource, REPLICATION_PREFIX from synapse.replication.tcp.resource import ReplicationStreamProtocolFactory from synapse.rest import ClientRestResource +from synapse.rest.consent.consent_resource import ConsentResource from synapse.rest.key.v1.server_key_resource import LocalKey from synapse.rest.key.v2 import KeyApiV2Resource from synapse.rest.media.v0.content_repository import ContentRepoResource @@ -182,6 +183,14 @@ class SynapseHomeServer(HomeServer): "/_matrix/client/versions": client_resource, }) + if name == "consent": + consent_resource = ConsentResource(self) + if compress: + consent_resource = gz_wrap(consent_resource) + resources.update({ + "/_matrix/consent": consent_resource, + }) + if name == "federation": resources.update({ FEDERATION_PREFIX: TransportLayerServer(self), diff --git a/synapse/config/__init__.py b/synapse/config/__init__.py index bfebb0f64..f2a5a41e9 100644 --- a/synapse/config/__init__.py +++ b/synapse/config/__init__.py @@ -12,3 +12,9 @@ # 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. + +from ._base import ConfigError + +# export ConfigError if somebody does import * +# this is largely a fudge to stop PEP8 moaning about the import +__all__ = ["ConfigError"] diff --git a/synapse/config/consent_config.py b/synapse/config/consent_config.py new file mode 100644 index 000000000..675fce091 --- /dev/null +++ b/synapse/config/consent_config.py @@ -0,0 +1,42 @@ +# -*- 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. + +from ._base import Config + +DEFAULT_CONFIG = """\ +# User Consent configuration +# +# uncomment and configure if enabling the 'consent' resource under 'listeners'. +# +# 'template_dir' gives the location of the templates for the HTML forms. +# This directory should contain one subdirectory per language (eg, 'en', 'fr'), +# and each language directory should contain the policy document (named as +# '.html') and a success page (success.html). +# +# 'default_version' gives the version of the policy document to serve up if +# there is no 'v' parameter. +# +# user_consent: +# template_dir: res/templates/privacy +# default_version: 1.0 +""" + + +class ConsentConfig(Config): + def read_config(self, config): + self.consent_config = config.get("user_consent") + + def default_config(self, **kwargs): + return DEFAULT_CONFIG diff --git a/synapse/config/homeserver.py b/synapse/config/homeserver.py index bf19cfee2..fb6bd3b42 100644 --- a/synapse/config/homeserver.py +++ b/synapse/config/homeserver.py @@ -1,5 +1,6 @@ # -*- coding: utf-8 -*- # Copyright 2014-2016 OpenMarket Ltd +# 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. @@ -12,7 +13,6 @@ # 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. - from .tls import TlsConfig from .server import ServerConfig from .logger import LoggingConfig @@ -37,6 +37,7 @@ from .push import PushConfig from .spam_checker import SpamCheckerConfig from .groups import GroupsConfig from .user_directory import UserDirectoryConfig +from .consent_config import ConsentConfig class HomeServerConfig(TlsConfig, ServerConfig, DatabaseConfig, LoggingConfig, @@ -45,12 +46,13 @@ class HomeServerConfig(TlsConfig, ServerConfig, DatabaseConfig, LoggingConfig, AppServiceConfig, KeyConfig, SAML2Config, CasConfig, JWTConfig, PasswordConfig, EmailConfig, WorkerConfig, PasswordAuthProviderConfig, PushConfig, - SpamCheckerConfig, GroupsConfig, UserDirectoryConfig,): + SpamCheckerConfig, GroupsConfig, UserDirectoryConfig, + ConsentConfig): pass if __name__ == '__main__': import sys sys.stdout.write( - HomeServerConfig().generate_config(sys.argv[1], sys.argv[2])[0] + HomeServerConfig().generate_config(sys.argv[1], sys.argv[2], True)[0] ) diff --git a/synapse/config/key.py b/synapse/config/key.py index 4b8fc063d..d1382ad9a 100644 --- a/synapse/config/key.py +++ b/synapse/config/key.py @@ -59,14 +59,20 @@ class KeyConfig(Config): self.expire_access_token = config.get("expire_access_token", False) + # a secret which is used to calculate HMACs for form values, to stop + # falsification of values + self.form_secret = config.get("form_secret", None) + def default_config(self, config_dir_path, server_name, is_generating_file=False, **kwargs): base_key_name = os.path.join(config_dir_path, server_name) if is_generating_file: macaroon_secret_key = random_string_with_symbols(50) + form_secret = '"%s"' % random_string_with_symbols(50) else: macaroon_secret_key = None + form_secret = 'null' return """\ macaroon_secret_key: "%(macaroon_secret_key)s" @@ -74,6 +80,10 @@ class KeyConfig(Config): # Used to enable access token expiration. expire_access_token: False + # a secret which is used to calculate HMACs for form values, to stop + # falsification of values + form_secret: %(form_secret)s + ## Signing Keys ## # Path to the signing key to sign messages with diff --git a/synapse/http/server.py b/synapse/http/server.py index f29e36f49..a38209770 100644 --- a/synapse/http/server.py +++ b/synapse/http/server.py @@ -13,7 +13,8 @@ # 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 cgi +from six.moves import http_client from synapse.api.errors import ( cs_exception, SynapseError, CodeMessageException, UnrecognizedRequestError, Codes @@ -44,6 +45,18 @@ import simplejson logger = logging.getLogger(__name__) +HTML_ERROR_TEMPLATE = """ + + + + Error {code} + + +

{msg}

+ + +""" + def wrap_json_request_handler(h): """Wraps a request handler method with exception handling. @@ -104,6 +117,65 @@ def wrap_json_request_handler(h): return wrap_request_handler_with_logging(wrapped_request_handler) +def wrap_html_request_handler(h): + """Wraps a request handler method with exception handling. + + Also adds logging as per wrap_request_handler_with_logging. + + The handler method must have a signature of "handle_foo(self, request)", + where "self" must have a "clock" attribute (and "request" must be a + SynapseRequest). + """ + def wrapped_request_handler(self, request): + d = defer.maybeDeferred(h, self, request) + d.addErrback(_return_html_error, request) + return d + + return wrap_request_handler_with_logging(wrapped_request_handler) + + +def _return_html_error(f, request): + """Sends an HTML error page corresponding to the given failure + + Args: + f (twisted.python.failure.Failure): + request (twisted.web.iweb.IRequest): + """ + if f.check(CodeMessageException): + cme = f.value + code = cme.code + msg = cme.msg + + if isinstance(cme, SynapseError): + logger.info( + "%s SynapseError: %s - %s", request, code, msg + ) + else: + logger.error( + "Failed handle request %r: %s", + request, + f.getTraceback().rstrip(), + ) + else: + code = http_client.INTERNAL_SERVER_ERROR + msg = "Internal server error" + + logger.error( + "Failed handle request %r: %s", + request, + f.getTraceback().rstrip(), + ) + + body = HTML_ERROR_TEMPLATE.format( + code=code, msg=cgi.escape(msg), + ).encode("utf-8") + request.setResponseCode(code) + request.setHeader(b"Content-Type", b"text/html; charset=utf-8") + request.setHeader(b"Content-Length", b"%i" % (len(body),)) + request.write(body) + finish_request(request) + + def wrap_request_handler_with_logging(h): """Wraps a request handler to provide logging and metrics @@ -134,7 +206,7 @@ def wrap_request_handler_with_logging(h): servlet_name = self.__class__.__name__ with request.processing(servlet_name): with PreserveLoggingContext(request_context): - d = h(self, request) + d = defer.maybeDeferred(h, self, request) # record the arrival of the request *after* # dispatching to the handler, so that the handler diff --git a/synapse/rest/consent/__init__.py b/synapse/rest/consent/__init__.py new file mode 100644 index 000000000..e69de29bb diff --git a/synapse/rest/consent/consent_resource.py b/synapse/rest/consent/consent_resource.py new file mode 100644 index 000000000..d79130227 --- /dev/null +++ b/synapse/rest/consent/consent_resource.py @@ -0,0 +1,210 @@ +# -*- 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. + +from hashlib import sha256 +import hmac +import logging +from os import path +from six.moves import http_client + +import jinja2 +from jinja2 import TemplateNotFound +from twisted.internet import defer +from twisted.web.resource import Resource +from twisted.web.server import NOT_DONE_YET + +from synapse.api.errors import NotFoundError, SynapseError, StoreError +from synapse.config import ConfigError +from synapse.http.server import ( + finish_request, + wrap_html_request_handler, +) +from synapse.http.servlet import parse_string +from synapse.types import UserID + + +# language to use for the templates. TODO: figure this out from Accept-Language +TEMPLATE_LANGUAGE = "en" + +logger = logging.getLogger(__name__) + +# use hmac.compare_digest if we have it (python 2.7.7), else just use equality +if hasattr(hmac, "compare_digest"): + compare_digest = hmac.compare_digest +else: + def compare_digest(a, b): + return a == b + + +class ConsentResource(Resource): + """A twisted Resource to display a privacy policy and gather consent to it + + When accessed via GET, returns the privacy policy via a template. + + When accessed via POST, records the user's consent in the database and + displays a success page. + + The config should include a template_dir setting which contains templates + for the HTML. The directory should contain one subdirectory per language + (eg, 'en', 'fr'), and each language directory should contain the policy + document (named as '.html') and a success page (success.html). + + Both forms take a set of parameters from the browser. For the POST form, + these are normally sent as form parameters (but may be query-params); for + GET requests they must be query params. These are: + + u: the complete mxid, or the localpart of the user giving their + consent. Required for both GET (where it is used as an input to the + template) and for POST (where it is used to find the row in the db + to update). + + h: hmac_sha256(secret, u), where 'secret' is the privacy_secret in the + config file. If it doesn't match, the request is 403ed. + + v: the version of the privacy policy being agreed to. + + For GET: optional, and defaults to whatever was set in the config + file. Used to choose the version of the policy to pick from the + templates directory. + + For POST: required; gives the value to be recorded in the database + against the user. + """ + def __init__(self, hs): + """ + Args: + hs (synapse.server.HomeServer): homeserver + """ + Resource.__init__(self) + + self.hs = hs + self.store = hs.get_datastore() + + # this is required by the request_handler wrapper + self.clock = hs.get_clock() + + consent_config = hs.config.consent_config + if consent_config is None: + raise ConfigError( + "Consent resource is enabled but user_consent section is " + "missing in config file.", + ) + + # daemonize changes the cwd to /, so make the path absolute now. + consent_template_directory = path.abspath( + consent_config["template_dir"], + ) + if not path.isdir(consent_template_directory): + raise ConfigError( + "Could not find template directory '%s'" % ( + consent_template_directory, + ), + ) + + loader = jinja2.FileSystemLoader(consent_template_directory) + self._jinja_env = jinja2.Environment(loader=loader) + + self._default_consent_verison = consent_config["default_version"] + + if hs.config.form_secret is None: + raise ConfigError( + "Consent resource is enabled but form_secret is not set in " + "config file. It should be set to an arbitrary secret string.", + ) + + self._hmac_secret = hs.config.form_secret.encode("utf-8") + + def render_GET(self, request): + self._async_render_GET(request) + return NOT_DONE_YET + + @wrap_html_request_handler + def _async_render_GET(self, request): + """ + Args: + request (twisted.web.http.Request): + """ + + version = parse_string(request, "v", + default=self._default_consent_verison) + username = parse_string(request, "u", required=True) + userhmac = parse_string(request, "h", required=True) + + self._check_hash(username, userhmac) + + try: + self._render_template( + request, "%s.html" % (version,), + user=username, userhmac=userhmac, version=version, + ) + except TemplateNotFound: + raise NotFoundError("Unknown policy version") + + def render_POST(self, request): + self._async_render_POST(request) + return NOT_DONE_YET + + @wrap_html_request_handler + @defer.inlineCallbacks + def _async_render_POST(self, request): + """ + Args: + request (twisted.web.http.Request): + """ + version = parse_string(request, "v", required=True) + username = parse_string(request, "u", required=True) + userhmac = parse_string(request, "h", required=True) + + self._check_hash(username, userhmac) + + if username.startswith('@'): + qualified_user_id = username + else: + qualified_user_id = UserID(username, self.hs.hostname).to_string() + + try: + yield self.store.user_set_consent_version(qualified_user_id, version) + except StoreError as e: + if e.code != 404: + raise + raise NotFoundError("Unknown user") + + try: + self._render_template(request, "success.html") + except TemplateNotFound: + raise NotFoundError("success.html not found") + + def _render_template(self, request, template_name, **template_args): + # get_template checks for ".." so we don't need to worry too much + # about path traversal here. + template_html = self._jinja_env.get_template( + path.join(TEMPLATE_LANGUAGE, template_name) + ) + html_bytes = template_html.render(**template_args).encode("utf8") + + request.setHeader(b"Content-Type", b"text/html; charset=utf-8") + request.setHeader(b"Content-Length", b"%i" % len(html_bytes)) + request.write(html_bytes) + finish_request(request) + + def _check_hash(self, userid, userhmac): + want_mac = hmac.new( + key=self._hmac_secret, + msg=userid, + digestmod=sha256, + ).hexdigest() + + if not compare_digest(want_mac, userhmac): + raise SynapseError(http_client.FORBIDDEN, "HMAC incorrect") diff --git a/synapse/server.py b/synapse/server.py index ebdea6b0c..21cde5b6f 100644 --- a/synapse/server.py +++ b/synapse/server.py @@ -97,6 +97,9 @@ class HomeServer(object): which must be implemented by the subclass. This code may call any of the required "get" methods on the instance to obtain the sub-dependencies that one requires. + + Attributes: + config (synapse.config.homeserver.HomeserverConfig): """ DEPENDENCIES = [ diff --git a/synapse/storage/registration.py b/synapse/storage/registration.py index a50717db2..6ffc39786 100644 --- a/synapse/storage/registration.py +++ b/synapse/storage/registration.py @@ -286,6 +286,24 @@ class RegistrationStore(RegistrationWorkerStore, "user_set_password_hash", user_set_password_hash_txn ) + def user_set_consent_version(self, user_id, consent_version): + """Updates the user table to record privacy policy consent + + Args: + user_id (str): full mxid of the user to update + consent_version (str): version of the policy the user has consented + to + + Raises: + StoreError(404) if user not found + """ + return self._simple_update_one( + table='users', + keyvalues={'name': user_id, }, + updatevalues={'consent_version': consent_version, }, + desc="user_set_consent_version" + ) + def user_delete_access_tokens(self, user_id, except_token_id=None, device_id=None): """ diff --git a/synapse/storage/schema/delta/48/add_user_consent.sql b/synapse/storage/schema/delta/48/add_user_consent.sql new file mode 100644 index 000000000..523749150 --- /dev/null +++ b/synapse/storage/schema/delta/48/add_user_consent.sql @@ -0,0 +1,18 @@ +/* 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. + */ + +/* record the version of the privacy policy the user has consented to + */ +ALTER TABLE users ADD COLUMN consent_version TEXT;