370 lines
		
	
	
		
			14 KiB
		
	
	
	
		
			Python
		
	
	
			
		
		
	
	
			370 lines
		
	
	
		
			14 KiB
		
	
	
	
		
			Python
		
	
	
# -*- coding: utf-8 -*-
 | 
						|
# 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.
 | 
						|
 | 
						|
import ujson as json
 | 
						|
import logging
 | 
						|
 | 
						|
from canonicaljson import encode_canonical_json
 | 
						|
from twisted.internet import defer
 | 
						|
 | 
						|
from synapse.api.errors import SynapseError, CodeMessageException
 | 
						|
from synapse.types import get_domain_from_id
 | 
						|
from synapse.util.logcontext import preserve_fn, make_deferred_yieldable
 | 
						|
from synapse.util.retryutils import NotRetryingDestination
 | 
						|
 | 
						|
logger = logging.getLogger(__name__)
 | 
						|
 | 
						|
 | 
						|
class E2eKeysHandler(object):
 | 
						|
    def __init__(self, hs):
 | 
						|
        self.store = hs.get_datastore()
 | 
						|
        self.federation = hs.get_replication_layer()
 | 
						|
        self.device_handler = hs.get_device_handler()
 | 
						|
        self.is_mine_id = hs.is_mine_id
 | 
						|
        self.clock = hs.get_clock()
 | 
						|
 | 
						|
        # doesn't really work as part of the generic query API, because the
 | 
						|
        # query request requires an object POST, but we abuse the
 | 
						|
        # "query handler" interface.
 | 
						|
        self.federation.register_query_handler(
 | 
						|
            "client_keys", self.on_federation_query_client_keys
 | 
						|
        )
 | 
						|
 | 
						|
    @defer.inlineCallbacks
 | 
						|
    def query_devices(self, query_body, timeout):
 | 
						|
        """ Handle a device key query from a client
 | 
						|
 | 
						|
        {
 | 
						|
            "device_keys": {
 | 
						|
                "<user_id>": ["<device_id>"]
 | 
						|
            }
 | 
						|
        }
 | 
						|
        ->
 | 
						|
        {
 | 
						|
            "device_keys": {
 | 
						|
                "<user_id>": {
 | 
						|
                    "<device_id>": {
 | 
						|
                        ...
 | 
						|
                    }
 | 
						|
                }
 | 
						|
            }
 | 
						|
        }
 | 
						|
        """
 | 
						|
        device_keys_query = query_body.get("device_keys", {})
 | 
						|
 | 
						|
        # separate users by domain.
 | 
						|
        # make a map from domain to user_id to device_ids
 | 
						|
        local_query = {}
 | 
						|
        remote_queries = {}
 | 
						|
 | 
						|
        for user_id, device_ids in device_keys_query.items():
 | 
						|
            if self.is_mine_id(user_id):
 | 
						|
                local_query[user_id] = device_ids
 | 
						|
            else:
 | 
						|
                remote_queries[user_id] = device_ids
 | 
						|
 | 
						|
        # Firt get local devices.
 | 
						|
        failures = {}
 | 
						|
        results = {}
 | 
						|
        if local_query:
 | 
						|
            local_result = yield self.query_local_devices(local_query)
 | 
						|
            for user_id, keys in local_result.items():
 | 
						|
                if user_id in local_query:
 | 
						|
                    results[user_id] = keys
 | 
						|
 | 
						|
        # Now attempt to get any remote devices from our local cache.
 | 
						|
        remote_queries_not_in_cache = {}
 | 
						|
        if remote_queries:
 | 
						|
            query_list = []
 | 
						|
            for user_id, device_ids in remote_queries.iteritems():
 | 
						|
                if device_ids:
 | 
						|
                    query_list.extend((user_id, device_id) for device_id in device_ids)
 | 
						|
                else:
 | 
						|
                    query_list.append((user_id, None))
 | 
						|
 | 
						|
            user_ids_not_in_cache, remote_results = (
 | 
						|
                yield self.store.get_user_devices_from_cache(
 | 
						|
                    query_list
 | 
						|
                )
 | 
						|
            )
 | 
						|
            for user_id, devices in remote_results.iteritems():
 | 
						|
                user_devices = results.setdefault(user_id, {})
 | 
						|
                for device_id, device in devices.iteritems():
 | 
						|
                    keys = device.get("keys", None)
 | 
						|
                    device_display_name = device.get("device_display_name", None)
 | 
						|
                    if keys:
 | 
						|
                        result = dict(keys)
 | 
						|
                        unsigned = result.setdefault("unsigned", {})
 | 
						|
                        if device_display_name:
 | 
						|
                            unsigned["device_display_name"] = device_display_name
 | 
						|
                        user_devices[device_id] = result
 | 
						|
 | 
						|
            for user_id in user_ids_not_in_cache:
 | 
						|
                domain = get_domain_from_id(user_id)
 | 
						|
                r = remote_queries_not_in_cache.setdefault(domain, {})
 | 
						|
                r[user_id] = remote_queries[user_id]
 | 
						|
 | 
						|
        # Now fetch any devices that we don't have in our cache
 | 
						|
        @defer.inlineCallbacks
 | 
						|
        def do_remote_query(destination):
 | 
						|
            destination_query = remote_queries_not_in_cache[destination]
 | 
						|
            try:
 | 
						|
                remote_result = yield self.federation.query_client_keys(
 | 
						|
                    destination,
 | 
						|
                    {"device_keys": destination_query},
 | 
						|
                    timeout=timeout
 | 
						|
                )
 | 
						|
 | 
						|
                for user_id, keys in remote_result["device_keys"].items():
 | 
						|
                    if user_id in destination_query:
 | 
						|
                        results[user_id] = keys
 | 
						|
 | 
						|
            except CodeMessageException as e:
 | 
						|
                failures[destination] = {
 | 
						|
                    "status": e.code, "message": e.message
 | 
						|
                }
 | 
						|
            except NotRetryingDestination as e:
 | 
						|
                failures[destination] = {
 | 
						|
                    "status": 503, "message": "Not ready for retry",
 | 
						|
                }
 | 
						|
            except Exception as e:
 | 
						|
                # include ConnectionRefused and other errors
 | 
						|
                failures[destination] = {
 | 
						|
                    "status": 503, "message": e.message
 | 
						|
                }
 | 
						|
 | 
						|
        yield make_deferred_yieldable(defer.gatherResults([
 | 
						|
            preserve_fn(do_remote_query)(destination)
 | 
						|
            for destination in remote_queries_not_in_cache
 | 
						|
        ]))
 | 
						|
 | 
						|
        defer.returnValue({
 | 
						|
            "device_keys": results, "failures": failures,
 | 
						|
        })
 | 
						|
 | 
						|
    @defer.inlineCallbacks
 | 
						|
    def query_local_devices(self, query):
 | 
						|
        """Get E2E device keys for local users
 | 
						|
 | 
						|
        Args:
 | 
						|
            query (dict[string, list[string]|None): map from user_id to a list
 | 
						|
                 of devices to query (None for all devices)
 | 
						|
 | 
						|
        Returns:
 | 
						|
            defer.Deferred: (resolves to dict[string, dict[string, dict]]):
 | 
						|
                 map from user_id -> device_id -> device details
 | 
						|
        """
 | 
						|
        local_query = []
 | 
						|
 | 
						|
        result_dict = {}
 | 
						|
        for user_id, device_ids in query.items():
 | 
						|
            if not self.is_mine_id(user_id):
 | 
						|
                logger.warning("Request for keys for non-local user %s",
 | 
						|
                               user_id)
 | 
						|
                raise SynapseError(400, "Not a user here")
 | 
						|
 | 
						|
            if not device_ids:
 | 
						|
                local_query.append((user_id, None))
 | 
						|
            else:
 | 
						|
                for device_id in device_ids:
 | 
						|
                    local_query.append((user_id, device_id))
 | 
						|
 | 
						|
            # make sure that each queried user appears in the result dict
 | 
						|
            result_dict[user_id] = {}
 | 
						|
 | 
						|
        results = yield self.store.get_e2e_device_keys(local_query)
 | 
						|
 | 
						|
        # Build the result structure, un-jsonify the results, and add the
 | 
						|
        # "unsigned" section
 | 
						|
        for user_id, device_keys in results.items():
 | 
						|
            for device_id, device_info in device_keys.items():
 | 
						|
                r = dict(device_info["keys"])
 | 
						|
                r["unsigned"] = {}
 | 
						|
                display_name = device_info["device_display_name"]
 | 
						|
                if display_name is not None:
 | 
						|
                    r["unsigned"]["device_display_name"] = display_name
 | 
						|
                result_dict[user_id][device_id] = r
 | 
						|
 | 
						|
        defer.returnValue(result_dict)
 | 
						|
 | 
						|
    @defer.inlineCallbacks
 | 
						|
    def on_federation_query_client_keys(self, query_body):
 | 
						|
        """ Handle a device key query from a federated server
 | 
						|
        """
 | 
						|
        device_keys_query = query_body.get("device_keys", {})
 | 
						|
        res = yield self.query_local_devices(device_keys_query)
 | 
						|
        defer.returnValue({"device_keys": res})
 | 
						|
 | 
						|
    @defer.inlineCallbacks
 | 
						|
    def claim_one_time_keys(self, query, timeout):
 | 
						|
        local_query = []
 | 
						|
        remote_queries = {}
 | 
						|
 | 
						|
        for user_id, device_keys in query.get("one_time_keys", {}).items():
 | 
						|
            if self.is_mine_id(user_id):
 | 
						|
                for device_id, algorithm in device_keys.items():
 | 
						|
                    local_query.append((user_id, device_id, algorithm))
 | 
						|
            else:
 | 
						|
                domain = get_domain_from_id(user_id)
 | 
						|
                remote_queries.setdefault(domain, {})[user_id] = device_keys
 | 
						|
 | 
						|
        results = yield self.store.claim_e2e_one_time_keys(local_query)
 | 
						|
 | 
						|
        json_result = {}
 | 
						|
        failures = {}
 | 
						|
        for user_id, device_keys in results.items():
 | 
						|
            for device_id, keys in device_keys.items():
 | 
						|
                for key_id, json_bytes in keys.items():
 | 
						|
                    json_result.setdefault(user_id, {})[device_id] = {
 | 
						|
                        key_id: json.loads(json_bytes)
 | 
						|
                    }
 | 
						|
 | 
						|
        @defer.inlineCallbacks
 | 
						|
        def claim_client_keys(destination):
 | 
						|
            device_keys = remote_queries[destination]
 | 
						|
            try:
 | 
						|
                remote_result = yield self.federation.claim_client_keys(
 | 
						|
                    destination,
 | 
						|
                    {"one_time_keys": device_keys},
 | 
						|
                    timeout=timeout
 | 
						|
                )
 | 
						|
                for user_id, keys in remote_result["one_time_keys"].items():
 | 
						|
                    if user_id in device_keys:
 | 
						|
                        json_result[user_id] = keys
 | 
						|
            except CodeMessageException as e:
 | 
						|
                failures[destination] = {
 | 
						|
                    "status": e.code, "message": e.message
 | 
						|
                }
 | 
						|
            except NotRetryingDestination as e:
 | 
						|
                failures[destination] = {
 | 
						|
                    "status": 503, "message": "Not ready for retry",
 | 
						|
                }
 | 
						|
            except Exception as e:
 | 
						|
                # include ConnectionRefused and other errors
 | 
						|
                failures[destination] = {
 | 
						|
                    "status": 503, "message": e.message
 | 
						|
                }
 | 
						|
 | 
						|
        yield make_deferred_yieldable(defer.gatherResults([
 | 
						|
            preserve_fn(claim_client_keys)(destination)
 | 
						|
            for destination in remote_queries
 | 
						|
        ]))
 | 
						|
 | 
						|
        logger.info(
 | 
						|
            "Claimed one-time-keys: %s",
 | 
						|
            ",".join((
 | 
						|
                "%s for %s:%s" % (key_id, user_id, device_id)
 | 
						|
                for user_id, user_keys in json_result.iteritems()
 | 
						|
                for device_id, device_keys in user_keys.iteritems()
 | 
						|
                for key_id, _ in device_keys.iteritems()
 | 
						|
            )),
 | 
						|
        )
 | 
						|
 | 
						|
        defer.returnValue({
 | 
						|
            "one_time_keys": json_result,
 | 
						|
            "failures": failures
 | 
						|
        })
 | 
						|
 | 
						|
    @defer.inlineCallbacks
 | 
						|
    def upload_keys_for_user(self, user_id, device_id, keys):
 | 
						|
        time_now = self.clock.time_msec()
 | 
						|
 | 
						|
        # TODO: Validate the JSON to make sure it has the right keys.
 | 
						|
        device_keys = keys.get("device_keys", None)
 | 
						|
        if device_keys:
 | 
						|
            logger.info(
 | 
						|
                "Updating device_keys for device %r for user %s at %d",
 | 
						|
                device_id, user_id, time_now
 | 
						|
            )
 | 
						|
            # TODO: Sign the JSON with the server key
 | 
						|
            changed = yield self.store.set_e2e_device_keys(
 | 
						|
                user_id, device_id, time_now, device_keys,
 | 
						|
            )
 | 
						|
            if changed:
 | 
						|
                # Only notify about device updates *if* the keys actually changed
 | 
						|
                yield self.device_handler.notify_device_update(user_id, [device_id])
 | 
						|
 | 
						|
        one_time_keys = keys.get("one_time_keys", None)
 | 
						|
        if one_time_keys:
 | 
						|
            yield self._upload_one_time_keys_for_user(
 | 
						|
                user_id, device_id, time_now, one_time_keys,
 | 
						|
            )
 | 
						|
 | 
						|
        # the device should have been registered already, but it may have been
 | 
						|
        # deleted due to a race with a DELETE request. Or we may be using an
 | 
						|
        # old access_token without an associated device_id. Either way, we
 | 
						|
        # need to double-check the device is registered to avoid ending up with
 | 
						|
        # keys without a corresponding device.
 | 
						|
        yield self.device_handler.check_device_registered(user_id, device_id)
 | 
						|
 | 
						|
        result = yield self.store.count_e2e_one_time_keys(user_id, device_id)
 | 
						|
 | 
						|
        defer.returnValue({"one_time_key_counts": result})
 | 
						|
 | 
						|
    @defer.inlineCallbacks
 | 
						|
    def _upload_one_time_keys_for_user(self, user_id, device_id, time_now,
 | 
						|
                                       one_time_keys):
 | 
						|
        logger.info(
 | 
						|
            "Adding one_time_keys %r for device %r for user %r at %d",
 | 
						|
            one_time_keys.keys(), device_id, user_id, time_now,
 | 
						|
        )
 | 
						|
 | 
						|
        # make a list of (alg, id, key) tuples
 | 
						|
        key_list = []
 | 
						|
        for key_id, key_obj in one_time_keys.items():
 | 
						|
            algorithm, key_id = key_id.split(":")
 | 
						|
            key_list.append((
 | 
						|
                algorithm, key_id, key_obj
 | 
						|
            ))
 | 
						|
 | 
						|
        # First we check if we have already persisted any of the keys.
 | 
						|
        existing_key_map = yield self.store.get_e2e_one_time_keys(
 | 
						|
            user_id, device_id, [k_id for _, k_id, _ in key_list]
 | 
						|
        )
 | 
						|
 | 
						|
        new_keys = []  # Keys that we need to insert. (alg, id, json) tuples.
 | 
						|
        for algorithm, key_id, key in key_list:
 | 
						|
            ex_json = existing_key_map.get((algorithm, key_id), None)
 | 
						|
            if ex_json:
 | 
						|
                if not _one_time_keys_match(ex_json, key):
 | 
						|
                    raise SynapseError(
 | 
						|
                        400,
 | 
						|
                        ("One time key %s:%s already exists. "
 | 
						|
                         "Old key: %s; new key: %r") %
 | 
						|
                        (algorithm, key_id, ex_json, key)
 | 
						|
                    )
 | 
						|
            else:
 | 
						|
                new_keys.append((algorithm, key_id, encode_canonical_json(key)))
 | 
						|
 | 
						|
        yield self.store.add_e2e_one_time_keys(
 | 
						|
            user_id, device_id, time_now, new_keys
 | 
						|
        )
 | 
						|
 | 
						|
 | 
						|
def _one_time_keys_match(old_key_json, new_key):
 | 
						|
    old_key = json.loads(old_key_json)
 | 
						|
 | 
						|
    # if either is a string rather than an object, they must match exactly
 | 
						|
    if not isinstance(old_key, dict) or not isinstance(new_key, dict):
 | 
						|
        return old_key == new_key
 | 
						|
 | 
						|
    # otherwise, we strip off the 'signatures' if any, because it's legitimate
 | 
						|
    # for different upload attempts to have different signatures.
 | 
						|
    old_key.pop("signatures", None)
 | 
						|
    new_key_copy = dict(new_key)
 | 
						|
    new_key_copy.pop("signatures", None)
 | 
						|
 | 
						|
    return old_key == new_key_copy
 |