CSM restrictions: Make 'LOAD_CLIENT_MODS' disable loading of 'builtin' (#8000)

Previously, when the CSM restriction 'LOAD_CLIENT_MODS' was used a
client was still able to add CSM code to 'builtin' to bypass that
restriction, because 'builtin' is not yet verified.

Until server-sent CSM and verifying of 'builtin' are complete, make
'LOAD_CLIENT_MODS' disable the loading of builtin.

Clarify code comments and messages to distinguish between client-side
modding and client-side scripting. 'Scripting' includes 'builtin',
'modding' does not.

diff --git a/builtin/settingtypes.txt b/builtin/settingtypes.txt
index d8d9ec3aba07feea43c4004a8f8aaca61581adb9..c312bdcf61bce301b1d13ee1958aed8f14227aaf 100644 (file)
--- a/builtin/settingtypes.txt
+++ b/builtin/settingtypes.txt
@@ -1189,14 +1189,16 @@ block_send_optimize_distance (Block send optimize distance) int 4 2
 #    so that the utility of noclip mode is reduced.
 server_side_occlusion_culling (Server side occlusion culling) bool true
 
-#    Restricts the access of certain client-side functions on servers
-#    Combine these byteflags below to restrict client-side features:
-#    LOAD_CLIENT_MODS: 1 (disable client mods loading)
+#    Restricts the access of certain client-side functions on servers.
+#    Combine the byteflags below to restrict client-side features, or set to 0
+#    for no restrictions:
+#    LOAD_CLIENT_MODS: 1 (disable loading client-provided mods)
 #    CHAT_MESSAGES: 2 (disable send_chat_message call client-side)
 #    READ_ITEMDEFS: 4 (disable get_item_def call client-side)
 #    READ_NODEDEFS: 8 (disable get_node_def call client-side)
 #    LOOKUP_NODES_LIMIT: 16 (limits get_node call client-side to
 #    csm_restriction_noderange)
+#    READ_PLAYERINFO: 32 (disable get_player_names call client-side)
 csm_restriction_flags (Client side modding restrictions) int 62
 
 #   If the CSM restriction for node range is enabled, get_node calls are limited

diff --git a/src/client/client.cpp b/src/client/client.cpp
index 17ee3a10aae685186ccbaeb6ef2b97b13109c0e4..3ba69333add3354d5b1dfed3b7a51c156e09dcf0 100644 (file)
--- a/src/client/client.cpp
+++ b/src/client/client.cpp
@@ -110,7 +110,8 @@ Client::Client(
        m_cache_save_interval = g_settings->getU16("server_map_save_interval");
 
        m_modding_enabled = g_settings->getBool("enable_client_modding");
-       // Only create the client script environment if client modding is enabled
+       // Only create the client script environment if client scripting is enabled by the
+       // client.
        if (m_modding_enabled) {
                m_script = new ClientScripting(this);
                m_env.setScript(m_script);
@@ -125,10 +126,22 @@ void Client::loadMods()
                return;
        }
 
-       // If client modding is not enabled, don't load client-provided CSM mods or
-       // builtin.
+       // If client scripting is disabled by the client, don't load builtin or
+       // client-provided mods.
        if (!m_modding_enabled) {
-               warningstream << "Client side mods are disabled by configuration." << std::endl;
+               warningstream << "Client side scripting is disabled by client." << std::endl;
+               return;
+       }
+
+       // If client scripting is disabled by the server, don't load builtin or
+       // client-provided mods.
+       // TODO Delete this code block when server-sent CSM and verifying of builtin are
+       // complete.
+       if (checkCSMRestrictionFlag(CSMRestrictionFlags::CSM_RF_LOAD_CLIENT_MODS)) {
+               warningstream << "Client-provided mod loading is disabled by server." <<
+                       std::endl;
+               // This line is needed because builtin is not loaded
+               m_modding_enabled = false;
                return;
        }
 
@@ -136,16 +149,19 @@ void Client::loadMods()
        scanModIntoMemory(BUILTIN_MOD_NAME, getBuiltinLuaPath());
        m_script->loadModFromMemory(BUILTIN_MOD_NAME);
 
-       // If the server has disabled client-provided CSM mod loading, don't load
-       // client-provided CSM mods. Builtin is loaded so needs verfying.
+       // TODO Uncomment when server-sent CSM and verifying of builtin are complete
+       /*
+       // Don't load client-provided mods if disabled by server
        if (checkCSMRestrictionFlag(CSMRestrictionFlags::CSM_RF_LOAD_CLIENT_MODS)) {
-               warningstream << "Client side mods are disabled by server." << std::endl;
+               warningstream << "Client-provided mod loading is disabled by server." <<
+                       std::endl;
                // If builtin integrity is wrong, disconnect user
                if (!checkBuiltinIntegrity()) {
-                       // @TODO disconnect user
+                       // TODO disconnect user
                }
                return;
        }
+       */
 
        ClientModConfiguration modconf(getClientModsLuaPath());
        m_mods = modconf.getMods();
@@ -155,7 +171,7 @@ void Client::loadMods()
        }
 
        // Print mods
-       infostream << "Client Loading mods: ";
+       infostream << "Client loading mods: ";
        for (const ModSpec &mod : m_mods)
                infostream << mod.name << " ";
        infostream << std::endl;
@@ -181,7 +197,7 @@ void Client::loadMods()
 
 bool Client::checkBuiltinIntegrity()
 {
-       // @TODO
+       // TODO
        return true;
 }
 

diff --git a/src/client/game.cpp b/src/client/game.cpp
index bd37bd58a9c5a78a6d3c4f8d80a3e3875eb24772..28f6a90ed8b3db045da603c8e7ce41bdfe09e47c 100644 (file)
--- a/src/client/game.cpp
+++ b/src/client/game.cpp
@@ -1891,7 +1891,7 @@ void Game::processKeyInput()
                if (client->moddingEnabled())
                        openConsole(0.2, L".");
                else
-                       m_game_ui->showStatusText(wgettext("CSM is disabled"));
+                       m_game_ui->showStatusText(wgettext("Client side scripting is disabled"));
        } else if (wasKeyDown(KeyType::CONSOLE)) {
                openConsole(core::clamp(g_settings->getFloat("console_height"), 0.1f, 1.0f));
        } else if (wasKeyDown(KeyType::FREEMOVE)) {
@@ -2554,7 +2554,7 @@ void Game::handleClientEvent_PlayerForceMove(ClientEvent *event, CameraOrientati
 
 void Game::handleClientEvent_Deathscreen(ClientEvent *event, CameraOrientation *cam)
 {
-       // If CSM enabled, deathscreen is handled by CSM code in
+       // If client scripting is enabled, deathscreen is handled by CSM code in
        // builtin/client/init.lua
        if (client->moddingEnabled())
                client->getScript()->on_death();

diff --git a/src/network/networkprotocol.h b/src/network/networkprotocol.h
index 6d6708482c28d579d0a267978dfd523aa071d718..96dfbe44f1ef347282ccc05a70813bd7324c6414 100644 (file)
--- a/src/network/networkprotocol.h
+++ b/src/network/networkprotocol.h
@@ -947,7 +947,11 @@ enum PlayerListModifer: u8
 
 enum CSMRestrictionFlags : u64 {
        CSM_RF_NONE = 0x00000000,
-       CSM_RF_LOAD_CLIENT_MODS = 0x00000001, // Disable mods provided by clients
+       // Until server-sent CSM and verifying of builtin are complete,
+       // 'CSM_RF_LOAD_CLIENT_MODS' also disables loading 'builtin'.
+       // When those are complete, this should return to only being a restriction on the
+       // loading of client mods.
+       CSM_RF_LOAD_CLIENT_MODS = 0x00000001, // Don't load client-provided mods or 'builtin'
        CSM_RF_CHAT_MESSAGES = 0x00000002, // Disable chat message sending from CSM
        CSM_RF_READ_ITEMDEFS = 0x00000004, // Disable itemdef lookups
        CSM_RF_READ_NODEDEFS = 0x00000008, // Disable nodedef lookups