Proper client timeout detection (#19906)

- Properly detect client timeout when logged into a character after a configurable time (default 60s) has passed without the client sending any packets.
- Fixes issues with crashed clients leaving characters in the world for a very long time (default 15 minutes), as well as edge case exploits involving intentionally pausing client execution for some amount of time.

3 files changed, 15 insertions, 9 deletions

diff --git a/src/server/game/Server/WorldSession.cpp b/src/server/game/Server/WorldSession.cpp
index a7a959bd0ea..05f69568507 100644
--- a/src/server/game/Server/WorldSession.cpp
+++ b/src/server/game/Server/WorldSession.cpp
@@ -137,7 +137,7 @@ WorldSession::WorldSession(uint32 id, std::string&& name, std::shared_ptr<WorldS
     if (sock)
     {
         m_Address = sock->GetRemoteIpAddress().to_string();
-        ResetTimeOutTime();
+        ResetTimeOutTime(false);
         LoginDatabase.PExecute("UPDATE account SET online = 1 WHERE id = %u;", GetAccountId());     // One-time query
     }
 
@@ -271,7 +271,8 @@ bool WorldSession::Update(uint32 diff, PacketFilter& updater)
     UpdateTimeOutTime(diff);
 
     ///- Before we process anything:
-    /// If necessary, kick the player from the character select screen
+    /// If necessary, kick the player because the client didn't send anything for too long
+    /// (or they've been idling in character select)
     if (IsConnectionIdle())
         m_Socket->CloseSocket();
 
@@ -633,9 +634,12 @@ char const* WorldSession::GetTrinityString(uint32 entry) const
     return sObjectMgr->GetTrinityString(entry, GetSessionDbLocaleIndex());
 }
 
-void WorldSession::ResetTimeOutTime()
+void WorldSession::ResetTimeOutTime(bool onlyActive)
 {
-    m_timeOutTime = int32(sWorld->getIntConfig(CONFIG_SOCKET_TIMEOUTTIME));
+    if (GetPlayer())
+        m_timeOutTime = int32(sWorld->getIntConfig(CONFIG_SOCKET_TIMEOUTTIME_ACTIVE));
+    else if (!onlyActive)
+        m_timeOutTime = int32(sWorld->getIntConfig(CONFIG_SOCKET_TIMEOUTTIME));
 }
 
 void WorldSession::Handle_NULL(WorldPacket& null)
@@ -1198,7 +1202,7 @@ void WorldSession::InitializeSessionCallback(SQLQueryHolder* realmHolder)
         SendAuthWaitQue(0);
 
     SetInQueue(false);
-    ResetTimeOutTime();
+    ResetTimeOutTime(false);
 
     SendAddonsInfo();
     SendClientCacheVersion(sWorld->getIntConfig(CONFIG_CLIENTCACHE_VERSION));
diff --git a/src/server/game/Server/WorldSession.h b/src/server/game/Server/WorldSession.h
index 9271fb06e06..237fa991456 100644
--- a/src/server/game/Server/WorldSession.h
+++ b/src/server/game/Server/WorldSession.h
@@ -439,7 +439,7 @@ class TC_GAME_API WorldSession
             m_timeOutTime -= int32(diff);
         }
 
-        void ResetTimeOutTime();
+        void ResetTimeOutTime(bool onlyActive);
 
         bool IsConnectionIdle() const
         {
diff --git a/src/server/game/Server/WorldSocket.cpp b/src/server/game/Server/WorldSocket.cpp
index 699c5a38a92..f759e2d27dd 100644
--- a/src/server/game/Server/WorldSocket.cpp
+++ b/src/server/game/Server/WorldSocket.cpp
@@ -357,7 +357,10 @@ WorldSocket::ReadDataHandlerResult WorldSocket::ReadDataHandler()
             return ReadDataHandlerResult::Error;
         }
         case CMSG_KEEP_ALIVE:
+            sessionGuard.lock();
             LogOpcodeText(opcode, sessionGuard);
+            if (_worldSession)
+                _worldSession->ResetTimeOutTime(true);
             break;
         default:
         {
@@ -378,9 +381,8 @@ WorldSocket::ReadDataHandlerResult WorldSocket::ReadDataHandler()
                 break;
             }
 
-            // Our Idle timer will reset on any non PING opcodes.
-            // Catches people idling on the login screen and any lingering ingame connections.
-            _worldSession->ResetTimeOutTime();
+            // Our Idle timer will reset on any non PING opcodes on login screen, allowing us to catch people idling.
+            _worldSession->ResetTimeOutTime(false);
 
             // Copy the packet to the heap before enqueuing
             _worldSession->QueuePacket(new WorldPacket(std::move(packet)));