Prevent downwards teleportation

mods/ENTITIES/mcl_mobs/mount.lua

@@ -175,7 +175,7 @@ function mobs.detach(player, offset)
 	minetest.after(0.1, function(name, pos)
 		local player = minetest.get_player_by_name(name)
 		if player then
-			player:set_pos(pos)
+			mcl_anticheat.set_pos(player, pos)
 		end
 	end, player:get_player_name(), pos)
 end

mods/ENVIRONMENT/mcl_void_damage/init.lua

@@ -66,7 +66,7 @@ minetest.register_globalstep(function(dtime)
 					-- If damage is disabled, we can't kill players.
 					-- So we just teleport the player back to spawn.
 					local spawn = mcl_spawn.get_player_spawn_pos(player)
-					player:set_pos(spawn)
+					mcl_anticheat.set_pos(player, spawn)
 					mcl_worlds.dimension_change(player, mcl_worlds.pos_to_dimension(spawn))
 					minetest.chat_send_player(player:get_player_name(), S("The void is off-limits to you!"))
 				elseif enable_damage and not is_immortal then

mods/ITEMS/REDSTONE/mesecons_mvps/init.lua

@@ -349,7 +349,7 @@ function mesecon.mvps_move_objects(pos, dir, nodestack)
 			local nn = minetest.get_node(np)
 			if not ((not minetest.registered_nodes[nn.name])
 			or minetest.registered_nodes[nn.name].walkable) then
-				obj:set_pos(np)
+				mcl_anticheat.set_pos(obj, np)
 			end
 		end
 	end

mods/ITEMS/mcl_beds/functions.lua

@@ -128,7 +128,7 @@ local function lay_down(player, pos, bed_pos, state, skip)
 		mcl_beds.pos[name] = nil
 		mcl_beds.bed_pos[name] = nil
 		if p then
-			player:set_pos(p)
+			mcl_anticheat.set_pos(player, p)
 		end
 
 		-- skip here to prevent sending player specific changes (used for leaving players)
@@ -183,7 +183,7 @@ local function lay_down(player, pos, bed_pos, state, skip)
 		player:get_meta():set_string("mcl_beds:sleeping", "true")
 		playerphysics.add_physics_factor(player, "speed", "mcl_beds:sleeping", 0)
 		playerphysics.add_physics_factor(player, "jump", "mcl_beds:sleeping", 0)
-		player:set_pos(bed_center)
+		mcl_anticheat.set_pos(player, bed_center)
 		mcl_player.player_attached[name] = true
 		hud_flags.wielditem = false
 		mcl_player.player_set_animation(player, "lay" , 0)

mods/ITEMS/mcl_end/chorus_plant.lua

@@ -515,7 +515,7 @@ local random_teleport = function(player)
 				if streak >= 2 then
 					-- JACKPOT! Now we can teleport.
 					local goal = {x=tpos.x, y=tpos.y-1.5, z=tpos.z}
-					player:set_pos(goal)
+					mcl_anticheat.set_pos(player, goal)
 					minetest.sound_play({name="mcl_end_teleport", gain=0.8}, {pos=goal, max_hear_distance=16}, true)
 					return true
 				end

mods/ITEMS/mcl_portals/portal_end.lua

@@ -211,7 +211,7 @@ function mcl_portals.end_teleport(obj, pos)
 	end
 
 	-- Teleport
-	obj:set_pos(target)
+	mcl_anticheat.set_pos(obj, target)
 
 	if obj:is_player() then
 		-- Look towards the main End island

mods/ITEMS/mcl_portals/portal_nether.lua

@@ -699,7 +699,7 @@ local function teleport_no_delay(obj, pos)
 	mcl_portals.nether_portal_cooloff[obj] = true
 
 	-- Teleport
-	obj:set_pos(target)
+	mcl_anticheat.set_pos(obj, target)
 
 	if is_player then
 		mcl_worlds.dimension_change(obj, mcl_worlds.pos_to_dimension(target))

mods/ITEMS/mcl_throwing/init.lua

@@ -364,7 +364,7 @@ local pearl_on_step = function(self, dtime)
 
 				local oldpos = player:get_pos()
 				-- Teleport and hurt player
-				player:set_pos(telepos)
+				mcl_anticheat.set_pos(player, telepos)
 				player:set_hp(player:get_hp() - 5, { type = "fall", from = "mod" })
 
 				-- 5% chance to spawn endermite at the player's origin

mods/MISC/findbiome/init.lua

@@ -259,7 +259,7 @@ do
 				if param == "default" then
 					local biome_pos = find_default_biome()
 					if biome_pos then
-						player:set_pos(biome_pos)
+						mcl_anticheat.set_pos(player, biome_pos)
 						return true, S("Biome found at @1.", minetest.pos_to_string(biome_pos))
 					else
 						return false, S("No biome found!")

mods/PLAYER/mcl_anticheat/init.lua

@@ -0,0 +1,35 @@
+local MAX_TP_DOWN = 100
+
+mcl_anticheat = {
+	positions = {}
+}
+
+function mcl_anticheat.set_pos(player, pos)
+	player:set_pos(pos)
+
+	if player:is_player() then
+		mcl_anticheat.positions[player] = pos
+	end
+end
+
+minetest.register_on_joinplayer(function(player)
+	mcl_anticheat.positions[player] = player:get_pos()
+end)
+
+minetest.register_on_leaveplayer(function(player)
+	mcl_anticheat.positions[player] = nil
+end)
+
+minetest.register_globalstep(function()
+	for _, player in pairs(minetest.get_connected_players()) do
+		local pos = player:get_pos()
+		local old_pos = mcl_anticheat.positions[player]
+
+		if old_pos.y - pos.y > MAX_TP_DOWN and not player:get_attach() then
+			player:set_pos(old_pos)
+		else
+			mcl_anticheat.positions[player] = pos
+		end
+	end
+
+end)

mods/PLAYER/mcl_anticheat/mod.conf

@@ -0,0 +1,2 @@
+name = mcl_anticheat
+author = Fleckenstein

mods/PLAYER/mcl_spawn/init.lua

@@ -490,7 +490,7 @@ end
 
 mcl_spawn.spawn = function(player)
 	local pos, in_bed = mcl_spawn.get_player_spawn_pos(player)
-	player:set_pos(pos)
+	mcl_anticheat.set_pos(player, pos)
 	return in_bed or success
 end