Line data    Source code

       1              : /*
       2              :  *   Famedly Matrix SDK
       3              :  *   Copyright (C) 2019, 2020, 2021 Famedly GmbH
       4              :  *
       5              :  *   This program is free software: you can redistribute it and/or modify
       6              :  *   it under the terms of the GNU Affero General Public License as
       7              :  *   published by the Free Software Foundation, either version 3 of the
       8              :  *   License, or (at your option) any later version.
       9              :  *
      10              :  *   This program is distributed in the hope that it will be useful,
      11              :  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
      12              :  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
      13              :  *   GNU Affero General Public License for more details.
      14              :  *
      15              :  *   You should have received a copy of the GNU Affero General Public License
      16              :  *   along with this program.  If not, see <https://www.gnu.org/licenses/>.
      17              :  */
      18              : 
      19              : import 'package:olm/olm.dart' as olm;
      20              : 
      21              : import 'package:matrix/encryption/utils/stored_inbound_group_session.dart';
      22              : import 'package:matrix/matrix.dart';
      23              : 
      24              : class SessionKey {
      25              :   /// The raw json content of the key
      26              :   Map<String, dynamic> content = <String, dynamic>{};
      27              : 
      28              :   /// Map of stringified-index to event id, so that we can detect replay attacks
      29              :   Map<String, String> indexes;
      30              : 
      31              :   /// Map of userId to map of deviceId to index, that we know that device receivied, e.g. sending it ourself.
      32              :   /// Used for automatically answering key requests
      33              :   Map<String, Map<String, int>> allowedAtIndex;
      34              : 
      35              :   /// Underlying olm [InboundGroupSession] object
      36              :   olm.InboundGroupSession? inboundGroupSession;
      37              : 
      38              :   /// Key for libolm pickle / unpickle
      39              :   final String key;
      40              : 
      41              :   /// Forwarding keychain
      42            6 :   List<String> get forwardingCurve25519KeyChain =>
      43           12 :       (content['forwarding_curve25519_key_chain'] != null
      44            6 :           ? List<String>.from(content['forwarding_curve25519_key_chain'])
      45              :           : null) ??
      46            4 :       <String>[];
      47              : 
      48              :   /// Claimed keys of the original sender
      49              :   late Map<String, String> senderClaimedKeys;
      50              : 
      51              :   /// Sender curve25519 key
      52              :   String senderKey;
      53              : 
      54              :   /// Is this session valid?
      55           14 :   bool get isValid => inboundGroupSession != null;
      56              : 
      57              :   /// roomId for this session
      58              :   String roomId;
      59              : 
      60              :   /// Id of this session
      61              :   String sessionId;
      62              : 
      63           23 :   SessionKey({
      64              :     required this.content,
      65              :     required this.inboundGroupSession,
      66              :     required this.key,
      67              :     Map<String, String>? indexes,
      68              :     Map<String, Map<String, int>>? allowedAtIndex,
      69              :     required this.roomId,
      70              :     required this.sessionId,
      71              :     required this.senderKey,
      72              :     required this.senderClaimedKeys,
      73            0 :   })  : indexes = indexes ?? <String, String>{},
      74            0 :         allowedAtIndex = allowedAtIndex ?? <String, Map<String, int>>{};
      75              : 
      76            6 :   SessionKey.fromDb(StoredInboundGroupSession dbEntry, this.key)
      77           12 :       : content = Event.getMapFromPayload(dbEntry.content),
      78           12 :         indexes = Event.getMapFromPayload(dbEntry.indexes)
      79            8 :             .catchMap((k, v) => MapEntry<String, String>(k, v)),
      80           12 :         allowedAtIndex = Event.getMapFromPayload(dbEntry.allowedAtIndex)
      81            9 :             .catchMap((k, v) => MapEntry(k, Map<String, int>.from(v))),
      82            6 :         roomId = dbEntry.roomId,
      83            6 :         sessionId = dbEntry.sessionId,
      84            6 :         senderKey = dbEntry.senderKey,
      85            6 :         inboundGroupSession = olm.InboundGroupSession() {
      86              :     final parsedSenderClaimedKeys =
      87           12 :         Event.getMapFromPayload(dbEntry.senderClaimedKeys)
      88           12 :             .catchMap((k, v) => MapEntry<String, String>(k, v));
      89              :     // we need to try...catch as the map used to be <String, int> and that will throw an error.
      90           12 :     senderClaimedKeys = (parsedSenderClaimedKeys.isNotEmpty)
      91              :         ? parsedSenderClaimedKeys
      92            3 :         : (content
      93            3 :                 .tryGetMap<String, dynamic>('sender_claimed_keys')
      94            0 :                 ?.catchMap((k, v) => MapEntry<String, String>(k, v)) ??
      95            9 :             (content['sender_claimed_ed25519_key'] is String
      96            0 :                 ? <String, String>{
      97            0 :                     'ed25519': content['sender_claimed_ed25519_key'],
      98              :                   }
      99            3 :                 : <String, String>{}));
     100              : 
     101              :     try {
     102           24 :       inboundGroupSession!.unpickle(key, dbEntry.pickle);
     103              :     } catch (e, s) {
     104            0 :       dispose();
     105            0 :       Logs().e('[LibOlm] Unable to unpickle inboundGroupSession', e, s);
     106              :     }
     107              :   }
     108              : 
     109           20 :   void dispose() {
     110           40 :     inboundGroupSession?.free();
     111           20 :     inboundGroupSession = null;
     112              :   }
     113              : }