allow uploading keys for cross-signing

4 files changed, 274 insertions, 3 deletions

diff --git a/synapse/storage/__init__.py b/synapse/storage/__init__.py
index 6b0ca80087..c20ba1001c 100644
--- a/synapse/storage/__init__.py
+++ b/synapse/storage/__init__.py
@@ -1,6 +1,6 @@
 # -*- coding: utf-8 -*-
 # Copyright 2014-2016 OpenMarket Ltd
-# Copyright 2018 New Vector Ltd
+# Copyright 2018,2019 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.
@@ -207,6 +207,9 @@ class DataStore(
         self._device_list_stream_cache = StreamChangeCache(
             "DeviceListStreamChangeCache", device_list_max
         )
+        self._user_signature_stream_cache = StreamChangeCache(
+            "UserSignatureStreamChangeCache", device_list_max
+        )
         self._device_list_federation_stream_cache = StreamChangeCache(
             "DeviceListFederationStreamChangeCache", device_list_max
         )
diff --git a/synapse/storage/devices.py b/synapse/storage/devices.py
index b73401bc26..ed372e2fc4 100644
--- a/synapse/storage/devices.py
+++ b/synapse/storage/devices.py
@@ -302,6 +302,41 @@ class DeviceWorkerStore(SQLBaseStore):
         """
         txn.execute(sql, (destination, stream_id))
 
+    @defer.inlineCallbacks
+    def add_user_signature_change_to_streams(self, from_user_id, user_ids):
+        """Persist that a user has made new signatures
+
+        Args:
+            from_user_id (str): the user who made the signatures
+            user_ids (list[str]): the users who were signed
+        """
+
+        with self._device_list_id_gen.get_next() as stream_id:
+            yield self.runInteraction(
+                "add_user_sig_change_to_streams",
+                self._add_user_signature_change_txn,
+                from_user_id,
+                user_ids,
+                stream_id,
+            )
+        defer.returnValue(stream_id)
+
+    def _add_user_signature_change_txn(self, txn, from_user_id, user_ids, stream_id):
+        txn.call_after(
+            self._user_signature_stream_cache.entity_has_changed,
+            from_user_id,
+            stream_id,
+        )
+        self._simple_insert_txn(
+            txn,
+            "user_signature_stream",
+            values={
+                "stream_id": stream_id,
+                "from_user_id": from_user_id,
+                "user_ids": json.dumps(user_ids),
+            },
+        )
+
     def get_device_stream_token(self):
         return self._device_list_id_gen.get_current_token()
 
@@ -440,6 +475,28 @@ class DeviceWorkerStore(SQLBaseStore):
             "get_users_whose_devices_changed", _get_users_whose_devices_changed_txn
         )
 
+    @defer.inlineCallbacks
+    def get_users_whose_signatures_changed(self, user_id, from_key):
+        """Get the users who have new cross-signing signatures made by `user_id` since
+        `from_key`.
+
+        Args:
+            user_id (str): the user who made the signatures
+            from_key (str): The device lists stream token
+        """
+        from_key = int(from_key)
+        if self._user_signature_stream_cache.has_entity_changed(user_id, from_key):
+            sql = """
+                SELECT DISTINCT user_ids FROM user_signature_stream
+                WHERE from_user_id = ? AND stream_id > ?
+            """
+            rows = yield self._execute(
+                "get_users_whose_signatures_changed", None, sql, user_id, from_key
+            )
+            defer.returnValue(set(user for row in rows for user in json.loads(row[0])))
+        else:
+            defer.returnValue(set())
+
     def get_all_device_list_changes_for_remotes(self, from_key, to_key):
         """Return a list of `(stream_id, user_id, destination)` which is the
         combined list of changes to devices, and which destinations need to be
diff --git a/synapse/storage/end_to_end_keys.py b/synapse/storage/end_to_end_keys.py
index 2fabb9e2cb..bb5f7d94eb 100644
--- a/synapse/storage/end_to_end_keys.py
+++ b/synapse/storage/end_to_end_keys.py
@@ -1,5 +1,7 @@
 # -*- coding: utf-8 -*-
 # Copyright 2015, 2016 OpenMarket Ltd
+# Copyright 2019 New Vector Ltd
+# Copyright 2019 The Matrix.org Foundation C.I.C.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -12,9 +14,11 @@
 # 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 time
+
 from six import iteritems
 
-from canonicaljson import encode_canonical_json
+from canonicaljson import encode_canonical_json, json
 
 from twisted.internet import defer
 
@@ -85,11 +89,12 @@ class EndToEndKeyWorkerStore(SQLBaseStore):
             "    k.key_json"
             " FROM devices d"
             "    %s JOIN e2e_device_keys_json k USING (user_id, device_id)"
-            " WHERE %s"
+            " WHERE (%s) AND NOT COALESCE(d.hidden, ?)"
         ) % (
             "LEFT" if include_all_devices else "INNER",
             " OR ".join("(" + q + ")" for q in query_clauses),
         )
+        query_params.append(False)
 
         txn.execute(sql, query_params)
         rows = self.cursor_to_dict(txn)
@@ -281,3 +286,168 @@ class EndToEndKeyStore(EndToEndKeyWorkerStore, SQLBaseStore):
         return self.runInteraction(
             "delete_e2e_keys_by_device", delete_e2e_keys_by_device_txn
         )
+
+    def _set_e2e_cross_signing_key_txn(self, txn, user_id, key_type, key):
+        """Set a user's cross-signing key.
+
+        Args:
+            txn (twisted.enterprise.adbapi.Connection): db connection
+            user_id (str): the user to set the signing key for
+            key_type (str): the type of key that is being set: either 'master'
+                for a master key, 'self_signing' for a self-signing key, or
+                'user_signing' for a user-signing key
+            key (dict): the key data
+        """
+        # the cross-signing keys need to occupy the same namespace as devices,
+        # since signatures are identified by device ID.  So add an entry to the
+        # device table to make sure that we don't have a collision with device
+        # IDs
+
+        # the 'key' dict will look something like:
+        # {
+        #   "user_id": "@alice:example.com",
+        #   "usage": ["self_signing"],
+        #   "keys": {
+        #     "ed25519:base64+self+signing+public+key": "base64+self+signing+public+key",
+        #   },
+        #   "signatures": {
+        #     "@alice:example.com": {
+        #       "ed25519:base64+master+public+key": "base64+signature"
+        #     }
+        #   }
+        # }
+        # The "keys" property must only have one entry, which will be the public
+        # key, so we just grab the first value in there
+        pubkey = next(iter(key["keys"].values()))
+        self._simple_insert(
+            "devices",
+            values={
+                "user_id": user_id,
+                "device_id": pubkey,
+                "display_name": key_type + " signing key",
+                "hidden": True,
+            },
+            desc="store_master_key_device",
+        )
+
+        # and finally, store the key itself
+        self._simple_insert(
+            "e2e_cross_signing_keys",
+            values={
+                "user_id": user_id,
+                "keytype": key_type,
+                "keydata": json.dumps(key),
+                "added_ts": time.time() * 1000,
+            },
+            desc="store_master_key",
+        )
+
+    def set_e2e_cross_signing_key(self, user_id, key_type, key):
+        """Set a user's cross-signing key.
+
+        Args:
+            user_id (str): the user to set the user-signing key for
+            key_type (str): the type of cross-signing key to set
+            key (dict): the key data
+        """
+        return self.runInteraction(
+            "add_e2e_cross_signing_key",
+            self._set_e2e_cross_signing_key_txn,
+            user_id,
+            key_type,
+            key,
+        )
+
+    def _get_e2e_cross_signing_key_txn(self, txn, user_id, key_type, from_user_id=None):
+        """Returns a user's cross-signing key.
+
+        Args:
+            txn (twisted.enterprise.adbapi.Connection): db connection
+            user_id (str): the user whose key is being requested
+            key_type (str): the type of key that is being set: either 'master'
+                for a master key, 'self_signing' for a self-signing key, or
+                'user_signing' for a user-signing key
+            from_user_id (str): if specified, signatures made by this user on
+                the key will be included in the result
+
+        Returns:
+            dict of the key data
+        """
+        sql = (
+            "SELECT keydata "
+            "  FROM e2e_cross_signing_keys "
+            " WHERE user_id = ? AND keytype = ? ORDER BY added_ts DESC LIMIT 1"
+        )
+        txn.execute(sql, (user_id, key_type))
+        row = txn.fetchone()
+        if not row:
+            return None
+        key = json.loads(row[0])
+
+        device_id = None
+        for k in key["keys"].values():
+            device_id = k
+
+        if from_user_id is not None:
+            sql = (
+                "SELECT key_id, signature "
+                "  FROM e2e_cross_signing_signatures "
+                " WHERE user_id = ? "
+                "   AND target_user_id = ? "
+                "   AND target_device_id = ? "
+            )
+            txn.execute(sql, (from_user_id, user_id, device_id))
+            row = txn.fetchone()
+            if row:
+                key.setdefault("signatures", {}).setdefault(from_user_id, {})[
+                    row[0]
+                ] = row[1]
+
+        return key
+
+    def get_e2e_cross_signing_key(self, user_id, key_type, from_user_id=None):
+        """Returns a user's cross-signing key.
+
+        Args:
+            user_id (str): the user whose self-signing key is being requested
+            key_type (str): the type of cross-signing key to get
+            from_user_id (str): if specified, signatures made by this user on
+                the self-signing key will be included in the result
+
+        Returns:
+            dict of the key data
+        """
+        return self.runInteraction(
+            "get_e2e_cross_signing_key",
+            self._get_e2e_cross_signing_key_txn,
+            user_id,
+            key_type,
+            from_user_id,
+        )
+
+    def store_e2e_cross_signing_signatures(self, user_id, signatures):
+        """Stores cross-signing signatures.
+
+        Args:
+            user_id (str): the user who made the signatures
+            signatures (iterable[(str, str, str, str)]): signatures to add - each
+                a tuple of (key_id, target_user_id, target_device_id, signature),
+                where key_id is the ID of the key (including the signature
+                algorithm) that made the signature, target_user_id and
+                target_device_id indicate the device being signed, and signature
+                is the signature of the device
+        """
+        return self._simple_insert_many(
+            "e2e_cross_signing_signatures",
+            [
+                {
+                    "user_id": user_id,
+                    "key_id": key_id,
+                    "target_user_id": target_user_id,
+                    "target_device_id": target_device_id,
+                    "signature": signature,
+                }
+                for (key_id, target_user_id, target_device_id, signature) in signatures
+            ],
+            "add_e2e_signing_key",
+        )
diff --git a/synapse/storage/schema/delta/56/signing_keys.sql b/synapse/storage/schema/delta/56/signing_keys.sql
index 51c96d3116..771740e970 100644
--- a/synapse/storage/schema/delta/56/signing_keys.sql
+++ b/synapse/storage/schema/delta/56/signing_keys.sql
@@ -13,6 +13,47 @@
  * limitations under the License.
  */
 
+-- cross-signing keys
+CREATE TABLE IF NOT EXISTS e2e_cross_signing_keys (
+    user_id TEXT NOT NULL,
+    -- the type of cross-signing key (master, user_signing, or self_signing)
+    keytype TEXT NOT NULL,
+    -- the full key information, as a json-encoded dict
+    keydata TEXT NOT NULL,
+    -- time that the key was added
+    added_ts BIGINT NOT NULL
+);
+
+CREATE UNIQUE INDEX e2e_cross_signing_keys_idx ON e2e_cross_signing_keys(user_id, keytype, added_ts);
+
+-- cross-signing signatures
+CREATE TABLE IF NOT EXISTS e2e_cross_signing_signatures (
+    -- user who did the signing
+    user_id TEXT NOT NULL,
+    -- key used to sign
+    key_id TEXT NOT NULL,
+    -- user who was signed
+    target_user_id TEXT NOT NULL,
+    -- device/key that was signed
+    target_device_id TEXT NOT NULL,
+    -- the actual signature
+    signature TEXT NOT NULL
+);
+
+CREATE UNIQUE INDEX e2e_cross_signing_signatures_idx ON e2e_cross_signing_signatures(user_id, target_user_id, target_device_id);
+
+-- stream of user signature updates
+CREATE TABLE IF NOT EXISTS user_signature_stream (
+    -- uses the same stream ID as device list stream
+    stream_id BIGINT NOT NULL,
+    -- user who did the signing
+    from_user_id TEXT NOT NULL,
+    -- list of users who were signed, as a JSON array
+    user_ids TEXT NOT NULL
+);
+
+CREATE UNIQUE INDEX user_signature_stream_idx ON user_signature_stream(stream_id);
+
 -- device list needs to know which ones are "real" devices, and which ones are
 -- just used to avoid collisions
 ALTER TABLE devices ADD COLUMN hidden BOOLEAN NULLABLE;