Core/Session: proper client timeout detection (#1232)

* Core/Session: proper client timeout detection

- 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.

src/server/game/Server/WorldSession.cpp

@@ -125,7 +125,7 @@ WorldSession::WorldSession(uint32 id, WorldSocket* sock, AccountTypes sec, uint8
     {
         m_Address = sock->GetRemoteAddress();
         sock->AddReference();
-        ResetTimeOutTime();
+        ResetTimeOutTime(false);
         LoginDatabase.PExecute("UPDATE account SET online = online | (1<<(%u-1)) WHERE id = %u;", realmID, GetAccountId());
     }
 
@@ -251,6 +251,9 @@ bool WorldSession::Update(uint32 diff, PacketFilter& updater)
     if (updater.ProcessLogout())
     {
         UpdateTimeOutTime(diff);
+        
+        /// 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();
     }

src/server/game/Server/WorldSession.h

@@ -355,9 +355,12 @@ class WorldSession
             else
                 m_timeOutTime -= diff;
         }
-        void ResetTimeOutTime()
+        void ResetTimeOutTime(bool onlyActive)
         {
-            m_timeOutTime = 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));
         }
         bool IsConnectionIdle() const
         {

src/server/game/Server/WorldSocket.cpp

@@ -681,8 +681,10 @@ int WorldSocket::ProcessIncoming(WorldPacket* new_pct)
                     return -1;
                 }
                 return HandleAuthSession (*new_pct);
-            case CMSG_KEEP_ALIVE:
-                return 0;
+            case CMSG_KEEP_ALIVE:           
+                if (m_Session)
+                    m_Session->ResetTimeOutTime(true);
+                break;
             default:
             {
                 ACE_GUARD_RETURN (LockType, Guard, m_SessionLock, -1);
@@ -691,7 +693,7 @@ int WorldSocket::ProcessIncoming(WorldPacket* new_pct)
                 {
                     // Our Idle timer will reset on any non PING opcodes.
                     // Catches people idling on the login screen and any lingering ingame connections.
-                    m_Session->ResetTimeOutTime();
+                    m_Session->ResetTimeOutTime(false);
 
                     // OK, give the packet to WorldSession
                     aptr.release();

src/server/game/World/World.cpp

@@ -375,7 +375,7 @@ bool World::RemoveQueuedPlayer(WorldSession* sess)
         if (*iter == sess)
         {
             sess->SetInQueue(false);
-            sess->ResetTimeOutTime();
+            sess->ResetTimeOutTime(false);
             iter = m_QueuedPlayer.erase(iter);
             found = true;
             break;
@@ -394,7 +394,7 @@ bool World::RemoveQueuedPlayer(WorldSession* sess)
     {
         WorldSession* pop_sess = m_QueuedPlayer.front();
         pop_sess->SetInQueue(false);
-        pop_sess->ResetTimeOutTime();
+        pop_sess->ResetTimeOutTime(false);
         pop_sess->SendAuthWaitQue(0);
         pop_sess->SendAddonsInfo();
 
@@ -690,6 +690,7 @@ void World::LoadConfigSettings(bool reload)
         m_int_configs[CONFIG_PORT_WORLD] = sConfigMgr->GetIntDefault("WorldServerPort", 8085);
 
     m_int_configs[CONFIG_SOCKET_TIMEOUTTIME] = sConfigMgr->GetIntDefault("SocketTimeOutTime", 900000);
+    m_int_configs[CONFIG_SOCKET_TIMEOUTTIME_ACTIVE] = sConfigMgr->GetIntDefault("SocketTimeOutTimeActive", 60000);
     m_int_configs[CONFIG_SESSION_ADD_DELAY] = sConfigMgr->GetIntDefault("SessionAddDelay", 10000);
 
     m_float_configs[CONFIG_GROUP_XP_DISTANCE] = sConfigMgr->GetFloatDefault("MaxGroupXPDistance", 74.0f);

src/server/game/World/World.h

@@ -330,6 +330,7 @@ enum WorldIntConfigs
     CONFIG_WARDEN_NUM_MEM_CHECKS,
     CONFIG_WARDEN_NUM_OTHER_CHECKS,
     CONFIG_BIRTHDAY_TIME,
+    CONFIG_SOCKET_TIMEOUTTIME_ACTIVE,
     INT_CONFIG_VALUE_COUNT
 };
 

src/server/worldserver/worldserver.conf.dist

@@ -220,6 +220,15 @@ GridUnload = 1
 
 SocketTimeOutTime = 900000
 
+#
+#    SocketTimeOutTimeActive
+#        Description: Time (in milliseconds) after which an idle connection is dropped while
+#                     logged into the world.
+#                     The client sends keepalive packets every 30 seconds. Values <= 30s are not recommended.
+#        Default:     60000 - (1 minute)
+
+SocketTimeOutTimeActive = 60000
+
 #
 #    SessionAddDelay
 #        Description: Time (in microseconds) that a network thread will sleep after authentication