add handling for ChestSizeSync packet

TShockAPI/GetDataHandlers.cs

@@ -144,7 +144,8 @@ public static void InitGetDataHandler()
 					{ PacketTypes.SyncCavernMonsterType, HandleSyncCavernMonsterType },
 					{ PacketTypes.SyncLoadout, HandleSyncLoadout },
 					{ PacketTypes.TeamChangeFromUI, HandlePlayerTeam }, // Same packet as PlayerTeam
-					{ PacketTypes.TEDeadCellsDisplayJar, HandleDisplayJar }
+					{ PacketTypes.TEDeadCellsDisplayJar, HandleDisplayJar },
+					{ PacketTypes.SyncChestSize, HandleChestSizeSync }
 				};
 		}
 
@@ -4980,6 +4981,60 @@ private static bool HandleDisplayJar(GetDataHandlerArgs args)
 			return false;
 		}
 
+		private static bool HandleChestSizeSync(GetDataHandlerArgs args)
+		{
+			short id = args.Data.ReadInt16();
+			short newSize = args.Data.ReadInt16();
+
+			if (id is < 0 or >= Main.maxChests) // chest is invalid
+				return true;
+
+			Chest chest = Main.chest[id];
+
+			if (chest == null)
+			{
+				TShock.Log.ConsoleDebug(GetString("GetDataHandlers / HandleChestSizeSync rejected from null chest {0}", args.Player.Name));
+				return true;
+			}
+
+			if (args.Player.IsBeingDisabled())
+			{
+				TShock.Log.ConsoleDebug(GetString("GetDataHandlers / HandleChestSizeSync rejected from disabled {0}", args.Player.Name));
+				args.Player.SendData(PacketTypes.SyncChestSize, "", id, chest.maxItems);
+				return true;
+			}
+
+			if (args.Player.IsBouncerThrottled())
+			{
+				TShock.Log.ConsoleDebug(GetString("GetDataHandlers / HandleChestSizeSync rejected from throttled {0}", args.Player.Name));
+				args.Player.SendData(PacketTypes.SyncChestSize, "", id, chest.maxItems);
+				return true;
+			}
+
+			if (!args.Player.HasPermission(Permissions.resizechests))
+			{
+				TShock.Log.ConsoleDebug(GetString("GetDataHandlers / HandleChestSizeSync rejected from no permission {0}", args.Player.Name));
+				args.Player.Kick(GetString("Exploit attempt detected!"), true);
+				return true;
+			}
+
+			if (!args.Player.HasBuildPermission(chest.x, chest.y))
+			{
+				TShock.Log.ConsoleDebug(GetString("GetDataHandlers / HandleChestSizeSync rejected from build {0}", args.Player.Name));
+				args.Player.SendData(PacketTypes.SyncChestSize, "", id, chest.maxItems);
+				return true;
+			}
+
+			if (newSize < 0) // size is invalid
+			{
+				TShock.Log.ConsoleDebug(GetString("GetDataHandlers / HandleChestSizeSync rejected from invalid size {0}", args.Player.Name));
+				args.Player.SendData(PacketTypes.SyncChestSize, "", id, chest.maxItems);
+				return true;
+			}
+
+			return false;
+		}
+
 
 		public enum DoorAction
 		{

TShockAPI/Permissions.cs

@@ -172,6 +172,10 @@ public static class Permissions
 
 		[Description("Prevents you from being disabled by abnormal MP.")]
 		public static readonly string ignoremp = "tshock.ignore.mp";
+
+
+		[Description("Player can resize chests. Warning: Dangerous permission to grant, very easy to abuse.")]
+		public static readonly string resizechests = "tshock.ignore.resizechests";
 		#endregion
 
 		#region tshock.item nodes