From 33300673b7a6f79802f691ac121e720cb44c0dfc Mon Sep 17 00:00:00 2001 From: Daniel Wagner-Hall Date: Wed, 24 Feb 2016 14:41:25 +0000 Subject: [PATCH] Generate guest access token on 3pid invites This means that following the same link across multiple sessions or devices can re-use the same guest account. Note that this is somewhat of an abuse vector; we can't throw up captchas on this flow, so this is a way of registering ephemeral accounts for spam, whose sign-up we don't rate limit. --- synapse/handlers/register.py | 15 +++++++ synapse/handlers/room.py | 8 ++++ synapse/storage/registration.py | 44 +++++++++++++++++++ .../delta/30/threepid_guest_access_tokens.sql | 24 ++++++++++ 4 files changed, 91 insertions(+) create mode 100644 synapse/storage/schema/delta/30/threepid_guest_access_tokens.sql diff --git a/synapse/handlers/register.py b/synapse/handlers/register.py index f8959e5d8..6d155d57e 100644 --- a/synapse/handlers/register.py +++ b/synapse/handlers/register.py @@ -349,3 +349,18 @@ class RegistrationHandler(BaseHandler): def auth_handler(self): return self.hs.get_handlers().auth_handler + + @defer.inlineCallbacks + def guest_access_token_for(self, medium, address, inviter_user_id): + access_token = yield self.store.get_3pid_guest_access_token(medium, address) + if access_token: + defer.returnValue(access_token) + + _, access_token = yield self.register( + generate_token=True, + make_guest=True + ) + access_token = yield self.store.save_or_get_3pid_guest_access_token( + medium, address, access_token, inviter_user_id + ) + defer.returnValue(access_token) diff --git a/synapse/handlers/room.py b/synapse/handlers/room.py index eb9700a35..d2de23a6c 100644 --- a/synapse/handlers/room.py +++ b/synapse/handlers/room.py @@ -848,6 +848,13 @@ class RoomMemberHandler(BaseHandler): user. """ + registration_handler = self.hs.get_handlers().registration_handler + guest_access_token = yield registration_handler.guest_access_token_for( + medium=medium, + address=address, + inviter_user_id=inviter_user_id, + ) + is_url = "%s%s/_matrix/identity/api/v1/store-invite" % ( id_server_scheme, id_server, ) @@ -864,6 +871,7 @@ class RoomMemberHandler(BaseHandler): "sender": inviter_user_id, "sender_display_name": inviter_display_name, "sender_avatar_url": inviter_avatar_url, + "guest_access_token": guest_access_token, } ) # TODO: Check for success diff --git a/synapse/storage/registration.py b/synapse/storage/registration.py index 967c732bd..03a9b66e4 100644 --- a/synapse/storage/registration.py +++ b/synapse/storage/registration.py @@ -387,3 +387,47 @@ class RegistrationStore(SQLBaseStore): "find_next_generated_user_id", _find_next_generated_user_id ))) + + @defer.inlineCallbacks + def get_3pid_guest_access_token(self, medium, address): + ret = yield self._simple_select_one( + "threepid_guest_access_tokens", + { + "medium": medium, + "address": address + }, + ["guest_access_token"], True, 'get_3pid_guest_access_token' + ) + if ret: + defer.returnValue(ret["guest_access_token"]) + defer.returnValue(None) + + @defer.inlineCallbacks + def save_or_get_3pid_guest_access_token( + self, medium, address, access_token, inviter_user_id + ): + """ + Gets the 3pid's guest access token if exists, else saves access_token. + + :param medium (str): Medium of the 3pid. Must be "email". + :param address (str): 3pid address. + :param access_token (str): The access token to persist if none is + already persisted. + :param inviter_user_id (str): User ID of the inviter. + :return (deferred str): Whichever access token is persisted at the end + of this function call. + """ + def insert(txn): + txn.execute( + "INSERT INTO threepid_guest_access_tokens " + "(medium, address, guest_access_token, first_inviter) " + "VALUES (?, ?, ?, ?)", + (medium, address, access_token, inviter_user_id) + ) + + try: + yield self.runInteraction("save_3pid_guest_access_token", insert) + defer.returnValue(access_token) + except self.database_engine.module.IntegrityError: + ret = yield self.get_3pid_guest_access_token(medium, address) + defer.returnValue(ret) diff --git a/synapse/storage/schema/delta/30/threepid_guest_access_tokens.sql b/synapse/storage/schema/delta/30/threepid_guest_access_tokens.sql new file mode 100644 index 000000000..0dd2f1360 --- /dev/null +++ b/synapse/storage/schema/delta/30/threepid_guest_access_tokens.sql @@ -0,0 +1,24 @@ +/* Copyright 2016 OpenMarket 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. + */ + +-- Stores guest account access tokens generated for unbound 3pids. +CREATE TABLE threepid_guest_access_tokens( + medium TEXT, -- The medium of the 3pid. Must be "email". + address TEXT, -- The 3pid address. + guest_access_token TEXT, -- The access token for a guest user for this 3pid. + first_inviter TEXT -- User ID of the first user to invite this 3pid to a room. +); + +CREATE UNIQUE INDEX threepid_guest_access_tokens_index ON threepid_guest_access_tokens(medium, address);