Merge pull request #198 from matrix-org/markjh/client-end-to-end-key-management

Client end to end key management API

5 files changed, 441 insertions, 2 deletions

diff --git a/synapse/rest/client/v2_alpha/__init__.py b/synapse/rest/client/v2_alpha/__init__.py
index 7d1aff4307..c3323d2a8a 100644
--- a/synapse/rest/client/v2_alpha/__init__.py
+++ b/synapse/rest/client/v2_alpha/__init__.py
@@ -18,7 +18,8 @@ from . import (
     filter,
     account,
     register,
-    auth
+    auth,
+    keys,
 )
 
 from synapse.http.server import JsonResource
@@ -38,3 +39,4 @@ class ClientV2AlphaRestResource(JsonResource):
         account.register_servlets(hs, client_resource)
         register.register_servlets(hs, client_resource)
         auth.register_servlets(hs, client_resource)
+        keys.register_servlets(hs, client_resource)
diff --git a/synapse/rest/client/v2_alpha/keys.py b/synapse/rest/client/v2_alpha/keys.py
new file mode 100644
index 0000000000..f031267751
--- /dev/null
+++ b/synapse/rest/client/v2_alpha/keys.py
@@ -0,0 +1,276 @@
+# -*- coding: utf-8 -*-
+# Copyright 2015 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.
+
+from twisted.internet import defer
+
+from synapse.api.errors import SynapseError
+from synapse.http.servlet import RestServlet
+from syutil.jsonutil import encode_canonical_json
+
+from ._base import client_v2_pattern
+
+import simplejson as json
+import logging
+
+logger = logging.getLogger(__name__)
+
+
+class KeyUploadServlet(RestServlet):
+    """
+    POST /keys/upload/<device_id> HTTP/1.1
+    Content-Type: application/json
+
+    {
+      "device_keys": {
+        "user_id": "<user_id>",
+        "device_id": "<device_id>",
+        "valid_until_ts": <millisecond_timestamp>,
+        "algorithms": [
+          "m.olm.curve25519-aes-sha256",
+        ]
+        "keys": {
+          "<algorithm>:<device_id>": "<key_base64>",
+        },
+        "signatures:" {
+          "<user_id>" {
+            "<algorithm>:<device_id>": "<signature_base64>"
+      } } },
+      "one_time_keys": {
+        "<algorithm>:<key_id>": "<key_base64>"
+      },
+    }
+    """
+    PATTERN = client_v2_pattern("/keys/upload/(?P<device_id>[^/]*)")
+
+    def __init__(self, hs):
+        super(KeyUploadServlet, self).__init__()
+        self.store = hs.get_datastore()
+        self.clock = hs.get_clock()
+        self.auth = hs.get_auth()
+
+    @defer.inlineCallbacks
+    def on_POST(self, request, device_id):
+        auth_user, client_info = yield self.auth.get_user_by_req(request)
+        user_id = auth_user.to_string()
+        # TODO: Check that the device_id matches that in the authentication
+        # or derive the device_id from the authentication instead.
+        try:
+            body = json.loads(request.content.read())
+        except:
+            raise SynapseError(400, "Invalid key JSON")
+        time_now = self.clock.time_msec()
+
+        # TODO: Validate the JSON to make sure it has the right keys.
+        device_keys = body.get("device_keys", None)
+        if device_keys:
+            logger.info(
+                "Updating device_keys for device %r for user %r at %d",
+                device_id, auth_user, time_now
+            )
+            # TODO: Sign the JSON with the server key
+            yield self.store.set_e2e_device_keys(
+                user_id, device_id, time_now,
+                encode_canonical_json(device_keys)
+            )
+
+        one_time_keys = body.get("one_time_keys", None)
+        if one_time_keys:
+            logger.info(
+                "Adding %d one_time_keys for device %r for user %r at %d",
+                len(one_time_keys), device_id, user_id, time_now
+            )
+            key_list = []
+            for key_id, key_json in one_time_keys.items():
+                algorithm, key_id = key_id.split(":")
+                key_list.append((
+                    algorithm, key_id, encode_canonical_json(key_json)
+                ))
+
+            yield self.store.add_e2e_one_time_keys(
+                user_id, device_id, time_now, key_list
+            )
+
+        result = yield self.store.count_e2e_one_time_keys(user_id, device_id)
+        defer.returnValue((200, {"one_time_key_counts": result}))
+
+    @defer.inlineCallbacks
+    def on_GET(self, request, device_id):
+        auth_user, client_info = yield self.auth.get_user_by_req(request)
+        user_id = auth_user.to_string()
+
+        result = yield self.store.count_e2e_one_time_keys(user_id, device_id)
+        defer.returnValue((200, {"one_time_key_counts": result}))
+
+
+class KeyQueryServlet(RestServlet):
+    """
+    GET /keys/query/<user_id> HTTP/1.1
+
+    GET /keys/query/<user_id>/<device_id> HTTP/1.1
+
+    POST /keys/query HTTP/1.1
+    Content-Type: application/json
+    {
+      "device_keys": {
+        "<user_id>": ["<device_id>"]
+    } }
+
+    HTTP/1.1 200 OK
+    {
+      "device_keys": {
+        "<user_id>": {
+          "<device_id>": {
+            "user_id": "<user_id>", // Duplicated to be signed
+            "device_id": "<device_id>", // Duplicated to be signed
+            "valid_until_ts": <millisecond_timestamp>,
+            "algorithms": [ // List of supported algorithms
+              "m.olm.curve25519-aes-sha256",
+            ],
+            "keys": { // Must include a ed25519 signing key
+              "<algorithm>:<key_id>": "<key_base64>",
+            },
+            "signatures:" {
+              // Must be signed with device's ed25519 key
+              "<user_id>/<device_id>": {
+                "<algorithm>:<key_id>": "<signature_base64>"
+              }
+              // Must be signed by this server.
+              "<server_name>": {
+                "<algorithm>:<key_id>": "<signature_base64>"
+    } } } } } }
+    """
+
+    PATTERN = client_v2_pattern(
+        "/keys/query(?:"
+        "/(?P<user_id>[^/]*)(?:"
+        "/(?P<device_id>[^/]*)"
+        ")?"
+        ")?"
+    )
+
+    def __init__(self, hs):
+        super(KeyQueryServlet, self).__init__()
+        self.store = hs.get_datastore()
+        self.auth = hs.get_auth()
+
+    @defer.inlineCallbacks
+    def on_POST(self, request, user_id, device_id):
+        logger.debug("onPOST")
+        yield self.auth.get_user_by_req(request)
+        try:
+            body = json.loads(request.content.read())
+        except:
+            raise SynapseError(400, "Invalid key JSON")
+        query = []
+        for user_id, device_ids in body.get("device_keys", {}).items():
+            if not device_ids:
+                query.append((user_id, None))
+            else:
+                for device_id in device_ids:
+                    query.append((user_id, device_id))
+        results = yield self.store.get_e2e_device_keys([(user_id, device_id)])
+        defer.returnValue(self.json_result(request, results))
+
+    @defer.inlineCallbacks
+    def on_GET(self, request, user_id, device_id):
+        auth_user, client_info = yield self.auth.get_user_by_req(request)
+        auth_user_id = auth_user.to_string()
+        if not user_id:
+            user_id = auth_user_id
+        if not device_id:
+            device_id = None
+        # Returns a map of user_id->device_id->json_bytes.
+        results = yield self.store.get_e2e_device_keys([(user_id, device_id)])
+        defer.returnValue(self.json_result(request, results))
+
+    def json_result(self, request, results):
+        json_result = {}
+        for user_id, device_keys in results.items():
+            for device_id, json_bytes in device_keys.items():
+                json_result.setdefault(user_id, {})[device_id] = json.loads(
+                    json_bytes
+                )
+        return (200, {"device_keys": json_result})
+
+
+class OneTimeKeyServlet(RestServlet):
+    """
+    GET /keys/take/<user-id>/<device-id>/<algorithm> HTTP/1.1
+
+    POST /keys/take HTTP/1.1
+    {
+      "one_time_keys": {
+        "<user_id>": {
+          "<device_id>": "<algorithm>"
+    } } }
+
+    HTTP/1.1 200 OK
+    {
+      "one_time_keys": {
+        "<user_id>": {
+          "<device_id>": {
+            "<algorithm>:<key_id>": "<key_base64>"
+    } } } }
+
+    """
+    PATTERN = client_v2_pattern(
+        "/keys/take(?:/?|(?:/"
+        "(?P<user_id>[^/]*)/(?P<device_id>[^/]*)/(?P<algorithm>[^/]*)"
+        ")?)"
+    )
+
+    def __init__(self, hs):
+        super(OneTimeKeyServlet, self).__init__()
+        self.store = hs.get_datastore()
+        self.auth = hs.get_auth()
+        self.clock = hs.get_clock()
+
+    @defer.inlineCallbacks
+    def on_GET(self, request, user_id, device_id, algorithm):
+        yield self.auth.get_user_by_req(request)
+        results = yield self.store.take_e2e_one_time_keys(
+            [(user_id, device_id, algorithm)]
+        )
+        defer.returnValue(self.json_result(request, results))
+
+    @defer.inlineCallbacks
+    def on_POST(self, request, user_id, device_id, algorithm):
+        yield self.auth.get_user_by_req(request)
+        try:
+            body = json.loads(request.content.read())
+        except:
+            raise SynapseError(400, "Invalid key JSON")
+        query = []
+        for user_id, device_keys in body.get("one_time_keys", {}).items():
+            for device_id, algorithm in device_keys.items():
+                query.append((user_id, device_id, algorithm))
+        results = yield self.store.take_e2e_one_time_keys(query)
+        defer.returnValue(self.json_result(request, results))
+
+    def json_result(self, request, results):
+        json_result = {}
+        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)
+                    }
+        return (200, {"one_time_keys": json_result})
+
+
+def register_servlets(hs, http_server):
+    KeyUploadServlet(hs).register(http_server)
+    KeyQueryServlet(hs).register(http_server)
+    OneTimeKeyServlet(hs).register(http_server)
diff --git a/synapse/storage/__init__.py b/synapse/storage/__init__.py
index c137f47820..e089d81675 100644
--- a/synapse/storage/__init__.py
+++ b/synapse/storage/__init__.py
@@ -37,6 +37,7 @@ from .rejections import RejectionsStore
 from .state import StateStore
 from .signatures import SignatureStore
 from .filtering import FilteringStore
+from .end_to_end_keys import EndToEndKeyStore
 
 
 import fnmatch
@@ -51,7 +52,7 @@ logger = logging.getLogger(__name__)
 
 # Remember to update this number every time a change is made to database
 # schema files, so the users will be informed on server restarts.
-SCHEMA_VERSION = 20
+SCHEMA_VERSION = 21
 
 dir_path = os.path.abspath(os.path.dirname(__file__))
 
@@ -74,6 +75,7 @@ class DataStore(RoomMemberStore, RoomStore,
                 PushRuleStore,
                 ApplicationServiceTransactionStore,
                 EventsStore,
+                EndToEndKeyStore,
                 ):
 
     def __init__(self, hs):
diff --git a/synapse/storage/end_to_end_keys.py b/synapse/storage/end_to_end_keys.py
new file mode 100644
index 0000000000..99dc864e46
--- /dev/null
+++ b/synapse/storage/end_to_end_keys.py
@@ -0,0 +1,125 @@
+# -*- coding: utf-8 -*-
+# Copyright 2015 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.
+
+from _base import SQLBaseStore
+
+
+class EndToEndKeyStore(SQLBaseStore):
+    def set_e2e_device_keys(self, user_id, device_id, time_now, json_bytes):
+        return self._simple_upsert(
+            table="e2e_device_keys_json",
+            keyvalues={
+                "user_id": user_id,
+                "device_id": device_id,
+            },
+            values={
+                "ts_added_ms": time_now,
+                "key_json": json_bytes,
+            }
+        )
+
+    def get_e2e_device_keys(self, query_list):
+        """Fetch a list of device keys.
+        Args:
+            query_list(list): List of pairs of user_ids and device_ids.
+        Returns:
+            Dict mapping from user-id to dict mapping from device_id to
+            key json byte strings.
+        """
+        def _get_e2e_device_keys(txn):
+            result = {}
+            for user_id, device_id in query_list:
+                user_result = result.setdefault(user_id, {})
+                keyvalues = {"user_id": user_id}
+                if device_id:
+                    keyvalues["device_id"] = device_id
+                rows = self._simple_select_list_txn(
+                    txn, table="e2e_device_keys_json",
+                    keyvalues=keyvalues,
+                    retcols=["device_id", "key_json"]
+                )
+                for row in rows:
+                    user_result[row["device_id"]] = row["key_json"]
+            return result
+        return self.runInteraction("get_e2e_device_keys", _get_e2e_device_keys)
+
+    def add_e2e_one_time_keys(self, user_id, device_id, time_now, key_list):
+        def _add_e2e_one_time_keys(txn):
+            for (algorithm, key_id, json_bytes) in key_list:
+                self._simple_upsert_txn(
+                    txn, table="e2e_one_time_keys_json",
+                    keyvalues={
+                        "user_id": user_id,
+                        "device_id": device_id,
+                        "algorithm": algorithm,
+                        "key_id": key_id,
+                    },
+                    values={
+                        "ts_added_ms": time_now,
+                        "key_json": json_bytes,
+                    }
+                )
+        return self.runInteraction(
+            "add_e2e_one_time_keys", _add_e2e_one_time_keys
+        )
+
+    def count_e2e_one_time_keys(self, user_id, device_id):
+        """ Count the number of one time keys the server has for a device
+        Returns:
+            Dict mapping from algorithm to number of keys for that algorithm.
+        """
+        def _count_e2e_one_time_keys(txn):
+            sql = (
+                "SELECT algorithm, COUNT(key_id) FROM e2e_one_time_keys_json"
+                " WHERE user_id = ? AND device_id = ?"
+                " GROUP BY algorithm"
+            )
+            txn.execute(sql, (user_id, device_id))
+            result = {}
+            for algorithm, key_count in txn.fetchall():
+                result[algorithm] = key_count
+            return result
+        return self.runInteraction(
+            "count_e2e_one_time_keys", _count_e2e_one_time_keys
+        )
+
+    def take_e2e_one_time_keys(self, query_list):
+        """Take a list of one time keys out of the database"""
+        def _take_e2e_one_time_keys(txn):
+            sql = (
+                "SELECT key_id, key_json FROM e2e_one_time_keys_json"
+                " WHERE user_id = ? AND device_id = ? AND algorithm = ?"
+                " LIMIT 1"
+            )
+            result = {}
+            delete = []
+            for user_id, device_id, algorithm in query_list:
+                user_result = result.setdefault(user_id, {})
+                device_result = user_result.setdefault(device_id, {})
+                txn.execute(sql, (user_id, device_id, algorithm))
+                for key_id, key_json in txn.fetchall():
+                    device_result[algorithm + ":" + key_id] = key_json
+                    delete.append((user_id, device_id, algorithm, key_id))
+            sql = (
+                "DELETE FROM e2e_one_time_keys_json"
+                " WHERE user_id = ? AND device_id = ? AND algorithm = ?"
+                " AND key_id = ?"
+            )
+            for user_id, device_id, algorithm, key_id in delete:
+                txn.execute(sql, (user_id, device_id, algorithm, key_id))
+            return result
+        return self.runInteraction(
+            "take_e2e_one_time_keys", _take_e2e_one_time_keys
+        )
diff --git a/synapse/storage/schema/delta/21/end_to_end_keys.sql b/synapse/storage/schema/delta/21/end_to_end_keys.sql
new file mode 100644
index 0000000000..95e27eb7ea
--- /dev/null
+++ b/synapse/storage/schema/delta/21/end_to_end_keys.sql
@@ -0,0 +1,34 @@
+/* Copyright 2015 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.
+ */
+
+
+CREATE TABLE IF NOT EXISTS e2e_device_keys_json (
+    user_id TEXT NOT NULL, -- The user these keys are for.
+    device_id TEXT NOT NULL, -- Which of the user's devices these keys are for.
+    ts_added_ms BIGINT NOT NULL, -- When the keys were uploaded.
+    key_json TEXT NOT NULL, -- The keys for the device as a JSON blob.
+    CONSTRAINT uniqueness UNIQUE (user_id, device_id)
+);
+
+
+CREATE TABLE IF NOT EXISTS e2e_one_time_keys_json (
+    user_id TEXT NOT NULL, -- The user this one-time key is for.
+    device_id TEXT NOT NULL, -- The device this one-time key is for.
+    algorithm TEXT NOT NULL, -- Which algorithm this one-time key is for.
+    key_id TEXT NOT NULL, -- An id for suppressing duplicate uploads.
+    ts_added_ms BIGINT NOT NULL, -- When this key was uploaded.
+    key_json TEXT NOT NULL, -- The key as a JSON blob.
+    CONSTRAINT uniqueness UNIQUE (user_id, device_id, algorithm, key_id)
+);