Client-Server Item Desyncronization Bugs

[Uleat]

I always forget to check for 'null' values on new stuff..usually that is already done...

I also changed the pointer reference when I was trying to figure this out..it currently works, but it could have the other way as well... (didn't check it.)


This is an ALPHA patch as well since it more proof of concept than a finished product.

[CSD Patch 2]

Index: client_packet.cpp
===================================================================
--- client_packet.cpp	(revision 2173)
+++ client_packet.cpp	(working copy)
@@ -3278,6 +3278,8 @@
 	return;
 }
 
+// 'CSD 11' - Added checks for illegal bagslot swaps..should help with certain cheats
+// - If a player has used a cheat that allows illegal item placement, they could beomce bugged at some point (especially lore items.)
 void Client::Handle_OP_MoveItem(const EQApplicationPacket *app)
 {
 	if(!CharacterID())
@@ -3291,6 +3293,7 @@
 	}
 
 	MoveItem_Struct* mi = (MoveItem_Struct*)app->pBuffer;
+
 	if(spellend_timer.Enabled() && casting_spell_id && !IsBardSong(casting_spell_id))
 	{
 		if(mi->from_slot != mi->to_slot && (mi->from_slot < 30 || mi->from_slot > 39) && IsValidSlot(mi->from_slot) && IsValidSlot(mi->to_slot))
@@ -3310,6 +3313,58 @@
 			return;
 		}
 	}
+
+	//* REMOVE OR REMARK OUT BEGIN FOR ALLOWING ILLEGAL BAGSLOT USE
+	bool hackflag = false;
+
+	if (mi->from_slot >=251 && mi->from_slot <=340) {
+		if (mi->from_slot > 330)
+			hackflag = true; // why are we moving from a cursor bagslot when you can't open it?
+		else {			
+			sint16 from_invslot = this->m_inv.CalcSlotId(mi->from_slot);
+			const ItemInst *from_invslotitem = GetInv().GetItem(from_invslot); 
+
+			if (!from_invslotitem) { // trying to move from bag slots when parent inventory slot is empty
+				hackflag = true;
+			}
+			else if (from_invslotitem->GetItem()->ItemClass==1) { // checking the parent inventory slot for container
+				if (this->m_inv.CalcBagIdx(mi->from_slot) > (from_invslotitem->GetItem()->BagSlots - 1))
+					hackflag = true; // trying to move from slots beyond parent container size
+			}
+			else { // trying to move from bag slots when inventory slot item is not a container
+				hackflag = true;
+			}
+		}
+	}
+
+	if (mi->to_slot >= 251 && mi->to_slot <=340) {
+		if (mi->to_slot > 330)
+			hackflag = true; // why are we moving to a cursor bagslot when you can't open it?
+		else {
+			sint16 to_invslot = this->m_inv.CalcSlotId(mi->to_slot);
+			const ItemInst *to_invslotitem = GetInv().GetItem(to_invslot);
+
+			if (!to_invslotitem) { // trying to move into bag slots when parent inventory slot is empty
+				hackflag = true;
+			}
+			else if (to_invslotitem->GetItem()->ItemClass==1) { // checking the parent inventory slot for container
+				if (this->m_inv.CalcBagIdx(mi->from_slot) > (to_invslotitem->GetItem()->BagSlots - 1))
+					hackflag = true; // trying to move into slots beyond parent container size
+			}
+			else { // trying to move into bag slots when inventory slot item is not a container
+				hackflag = true;
+			}
+		}
+	}
+
+	if (hackflag) {
+		Message(13, "Hack attempt detected: Illegal use of inventory bagslots!");
+		// TODO: Decide whether to log player as hacker
+		// Kick();
+		// return;
+	}
+	// REMOVE OR REMARK OUT END FOR ALLOWING ILLEGAL BAGSLOT USE */
+
 	SwapItem(mi);
 	return;
 }

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