[CSM] Add flavour limits controlled by server (#5930)

* [CSM] Add flavour limits controlled by server

Server send flavour limits to client permitting to disable or limit some Lua calls

* Add limits for reading nodedefs and itemdefs

* flavour: Add lookup node limits

* Merge get_node_or_nil into get_node.

Sending fake node doesn't make sense in CSM, just return nil if node is not available for any reason

* Add node range customization when noderange flavour is enabled (default 8 nodes)

* Limit nodes range & disable chat message sending by default

* Bump protocol version

1 files changed, 10 insertions, 0 deletions

diff --git a/src/script/lua_api/l_env.cpp b/src/script/lua_api/l_env.cpp
index 3a4ba89f3..2a57ca59b 100644
--- a/src/script/lua_api/l_env.cpp
+++ b/src/script/lua_api/l_env.cpp
@@ -25,6 +25,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include "lua_api/l_vmanip.h"
 #include "common/c_converter.h"
 #include "common/c_content.h"
+#include <algorithm>
 #include "scripting_server.h"
 #include "environment.h"
 #include "server.h"
@@ -726,6 +727,15 @@ int ModApiEnvMod::l_find_node_near(lua_State *L)
 	}
 
 	int start_radius = (lua_toboolean(L, 4)) ? 0 : 1;
+
+#ifndef SERVER
+	// Client API limitations
+	if (getClient(L) &&
+			getClient(L)->checkCSMFlavourLimit(CSMFlavourLimit::CSM_FL_LOOKUP_NODES)) {
+		radius = std::max<int>(radius, getClient(L)->getCSMNodeRangeLimit());
+	}
+#endif
+
 	for (int d = start_radius; d <= radius; d++) {
 		std::vector<v3s16> list = FacePositionCache::getFacePositions(d);
 		for (std::vector<v3s16>::iterator i = list.begin();