allow uploading keys for cross-signing

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",
+        )