From 2ab6eb2a0c799a9c4dc9b34d7c3f2ccb9c8ab5e4 Mon Sep 17 00:00:00 2001
From: Christian Pauly <christian-pauly@posteo.de>
Date: Thu, 20 Feb 2020 15:29:15 +0000
Subject: [PATCH] [Client] Dont create new inbound session when session matches

---
 lib/src/client.dart | 16 +++++++++++++---
 lib/src/room.dart   |  5 ++++-
 2 files changed, 17 insertions(+), 4 deletions(-)

diff --git a/lib/src/client.dart b/lib/src/client.dart
index 0727991..b5ebf7e 100644
--- a/lib/src/client.dart
+++ b/lib/src/client.dart
@@ -1025,7 +1025,10 @@ class Client {
         try {
           toDeviceEvent = decryptToDeviceEvent(toDeviceEvent);
         } catch (e) {
-          print("[LibOlm] Could not decrypt to device event: " + e.toString());
+          print(
+              "[LibOlm] Could not decrypt to device event from ${toDeviceEvent.sender}: " +
+                  e.toString());
+          print(toDeviceEvent.sender);
           toDeviceEvent = ToDeviceEvent.fromJson(events[i]);
         }
       }
@@ -1320,7 +1323,9 @@ class Client {
           Room room = getRoomById(toDeviceEvent.content["room_id"]);
           if (room != null && toDeviceEvent.content["session_id"] is String) {
             final String sessionId = toDeviceEvent.content["session_id"];
-            room.setSessionKey(sessionId, toDeviceEvent.content);
+            if (room != null) {
+              room.setSessionKey(sessionId, toDeviceEvent.content);
+            }
           }
           break;
       }
@@ -1570,7 +1575,11 @@ class Client {
     List<olm.Session> existingSessions = olmSessions[senderKey];
     if (existingSessions != null) {
       for (olm.Session session in existingSessions) {
-        if ((type == 0 && session.matches_inbound(body) == 1) || type == 1) {
+        if (type == 0 && session.matches_inbound(body) != 0) {
+          plaintext = session.decrypt(type, body);
+          storeOlmSession(senderKey, session);
+          break;
+        } else if (type == 1) {
           try {
             plaintext = session.decrypt(type, body);
             storeOlmSession(senderKey, session);
@@ -1679,6 +1688,7 @@ class Client {
       };
       final olm.EncryptResult encryptResult =
           existingSessions.first.encrypt(json.encode(payload));
+      storeOlmSession(device.curve25519Key, existingSessions.first);
       encryptedMessage["ciphertext"][device.curve25519Key] = {
         "type": encryptResult.type,
         "body": encryptResult.body,
diff --git a/lib/src/room.dart b/lib/src/room.dart
index cfd7c79..176e6ff 100644
--- a/lib/src/room.dart
+++ b/lib/src/room.dart
@@ -836,7 +836,7 @@ class Room {
           .getItem("/clients/${client.deviceID}/rooms/${this.id}/session_keys");
       if (sessionKeysPickle?.isNotEmpty ?? false) {
         final Map<String, dynamic> map = json.decode(sessionKeysPickle);
-        this._sessionKeys = {};
+        if (this._sessionKeys == null) this._sessionKeys = {};
         for (var entry in map.entries) {
           try {
             this._sessionKeys[entry.key] =
@@ -848,6 +848,9 @@ class Room {
         }
       }
     }
+    await client.storeAPI?.setItem(
+        "/clients/${client.deviceID}/rooms/${this.id}/session_keys",
+        json.encode(sessionKeys));
     _fullyRestored = true;
   }