WIP checkpoint: Research and design GDScript sandboxing approach

sandbox_probe/probe5.gd

@@ -1,7 +1,7 @@
 extends Node
 
 func _ready():
-	print("=== SANDBOX PROBE 5: Corrected Sandboxing Mechanisms (Godot 4.6.2) ===")
+	print("=== SANDBOX PROBE 5b: Corrected Sandboxing Mechanisms (Godot 4.6.2) ===")
 	probe_script_loading()
 	probe_os_apis()
 	probe_file_access()
@@ -11,15 +11,13 @@ func _ready():
 	probe_engine_singletons()
 	probe_worker_threads()
 	probe_project_settings()
-	probe_scriptserver()
 	probe_script_restrictions()
 	probe_allowlist()
-	print("=== SANDBOX PROBE 5 END ===")
+	print("=== SANDBOX PROBE 5b END ===")
 	get_tree().quit()
 
 func probe_script_loading():
 	print("--- Script loading ---")
-	# Can we load a GDScript from a string at runtime?
 	var gd = GDScript.new()
 	gd.source_code = "extends RefCounted\nfunc hello():\n\treturn 42\n"
 	var err = gd.reload()
@@ -27,63 +25,51 @@ func probe_script_loading():
 	if err == OK:
 		var inst = gd.new()
 		print("  instantiated, hello()=", inst.call("hello"))
-	# Can we load a script resource from a path?
 	var res = load("res://test_script.gd")
 	print("load('res://test_script.gd') = ", res)
-	# Can we get the source code back from a loaded script?
 	if res:
 		print("  get_source_code() available: ", res.has_method("get_source_code"))
-	# Can we get the AST / parse tree? (instance methods)
 	print("  GDScript instance has 'get_ast': ", gd.has_method("get_ast"))
 	print("  GDScript instance has 'get_parser': ", gd.has_method("get_parser"))
-	# Can we get the list of methods?
 	print("  GDScript instance has 'get_script_method_list': ", gd.has_method("get_script_method_list"))
-	# Can we get the list of member variables?
 	print("  GDScript instance has 'get_script_property_list': ", gd.has_method("get_script_property_list"))
-	# Can we get the script's base class?
 	print("  GDScript instance has 'get_instance_base_type': ", gd.has_method("get_instance_base_type"))
-	# Can we get the script's resource path?
+	# Can we get the list of static methods on GDScript class?
-	print("  GDScript instance has 'get_path': ", gd.has_method("get_path"))
+	var gd_methods = GDScript.get_method_list()
+	var gd_method_names = []
+	for m in gd_methods:
+		gd_method_names.append(String(m.name))
+	print("  GDScript static methods: ", gd_method_names)
 
 func probe_os_apis():
 	print("--- OS APIs ---")
-	# Can we execute shell commands?
 	var out = []
 	var exit_code = OS.execute("echo", ["hello"], out)
 	print("OS.execute('echo') exit=", exit_code, " out=", out)
-	# Environment access
 	print("OS.get_environment('HOME') = ", OS.get_environment("HOME"))
-	# Process spawning
 	print("OS has 'create_process': ", OS.has_method("create_process"))
-	# Can we get the command line?
 	print("OS.get_cmdline_args() = ", OS.get_cmdline_args())
-	# Can we get user data dir?
 	print("OS.get_user_data_dir() = ", OS.get_user_data_dir())
-	# Can we get executable path?
 	print("OS.get_executable_path() = ", OS.get_executable_path())
 
 func probe_file_access():
 	print("--- File access ---")
-	# Can we read arbitrary files?
 	var f = FileAccess.open("/etc/hostname", FileAccess.READ)
 	print("FileAccess.open('/etc/hostname') = ", f)
 	if f:
 		print("  content: ", f.get_as_text())
 		f.close()
-	# Can we write outside the project?
 	var w = FileAccess.open("/tmp/godot_probe_write.txt", FileAccess.WRITE)
 	print("FileAccess.open('/tmp/...', WRITE) = ", w)
 	if w:
 		w.store_string("probe")
 		w.close()
 		print("  wrote to /tmp OK")
-	# Can we list directories?
 	var dir = DirAccess.open("/")
 	print("DirAccess.open('/') = ", dir)
 	if dir:
 		var names = dir.get_files()
 		print("  root files count: ", names.size())
-	# Can we access res:// and user:// ?
 	var res_dir = DirAccess.open("res://")
 	print("DirAccess.open('res://') = ", res_dir)
 	var user_dir = DirAccess.open("user://")
@@ -91,83 +77,63 @@ func probe_file_access():
 
 func probe_network():
 	print("--- Network ---")
-	# Can we open raw sockets?
 	var tcp = TCPServer.new()
 	var bind_err = tcp.listen(0)
 	print("TCPServer.listen(0) err=", bind_err)
-	# HTTP client
 	var http = HTTPClient.new()
 	print("HTTPClient instantiated: ", http != null)
-	# Can we make HTTP requests?
 	var http_req = HTTPRequest.new()
 	print("HTTPRequest instantiated: ", http_req != null)
-	# PacketPeerUDP
 	var udp = PacketPeerUDP.new()
 	print("PacketPeerUDP instantiated: ", udp != null)
-	# WebSocket
 	var ws = WebSocketPeer.new()
 	print("WebSocketPeer instantiated: ", ws != null)
 
 func probe_classdb():
 	print("--- ClassDB ---")
-	# ClassDB is the registry of all engine classes
 	print("ClassDB.class_exists('OS'): ", ClassDB.class_exists("OS"))
 	print("ClassDB.class_exists('FileAccess'): ", ClassDB.class_exists("FileAccess"))
 	print("ClassDB.class_exists('TCPServer'): ", ClassDB.class_exists("TCPServer"))
 	print("ClassDB.class_exists('HTTPClient'): ", ClassDB.class_exists("HTTPClient"))
-	# Can we enumerate all classes?
 	var class_list = ClassDB.get_class_list()
 	print("ClassDB.get_class_list() count: ", class_list.size())
-	# Can we get methods of a class?
 	var os_methods = ClassDB.class_get_method_list("OS")
 	print("OS method count: ", os_methods.size())
-	# Can we get properties of a class?
-	var os_props = ClassDB.class_get_property_list("OS")
-	print("OS property count: ", os_props.size())
-	# Can we instantiate a class by name?
 	var inst = ClassDB.instantiate("Node")
 	print("ClassDB.instantiate('Node') = ", inst)
-	# Can we check if a class is a singleton? (static method on ClassDB)
+	# Can we enumerate ClassDB methods to see what's available?
-	print("ClassDB has 'class_get_singleton': ", ClassDB.has_method("class_get_singleton"))
+	var classdb_methods = ClassDB.get_method_list()
-	# Can we get the singleton instance of OS?
+	var classdb_method_names = []
-	var os_singleton = ClassDB.class_get_singleton("OS")
+	for m in classdb_methods:
-	print("ClassDB.class_get_singleton('OS') = ", os_singleton)
+		classdb_method_names.append(String(m.name))
-	# Can we check what methods are available on the singleton?
+	print("  ClassDB methods: ", classdb_method_names)
-	if os_singleton:
-		print("  OS singleton has 'execute': ", os_singleton.has_method("execute"))
-		print("  OS singleton has 'get_environment': ", os_singleton.has_method("get_environment"))
 
 func probe_expression_engine():
 	print("--- Expression engine ---")
-	# Godot has an Expression class for evaluating expressions safely
 	var expr = Expression.new()
 	var err = expr.parse("1 + 2")
 	print("Expression.parse('1 + 2') err=", err)
 	if err == OK:
 		var result = expr.execute()
 		print("  Expression.execute() = ", result)
-	# Can Expression access OS?
 	var expr2 = Expression.new()
 	err = expr2.parse("OS.get_environment('HOME')")
 	print("Expression.parse('OS.get_environment') err=", err)
 	if err == OK:
 		var result2 = expr2.execute()
 		print("  Expression.execute() = ", result2)
-	# Expression with base_instance
 	var expr3 = Expression.new()
 	err = expr3.parse("get_environment('HOME')", ["OS"])
 	print("Expression.parse with base_instance err=", err)
 	if err == OK:
 		var result3 = expr3.execute([], OS)
 		print("  Expression.execute with OS base = ", result3)
-	# Can Expression call arbitrary methods?
 	var expr4 = Expression.new()
 	err = expr4.parse("FileAccess.open('/etc/hostname', 1)")
 	print("Expression.parse('FileAccess.open') err=", err)
 	if err == OK:
 		var result4 = expr4.execute()
 		print("  Expression.execute() = ", result4)
-	# Can Expression access the scene tree?
 	var expr5 = Expression.new()
 	err = expr5.parse("get_tree().quit()")
 	print("Expression.parse('get_tree().quit()') err=", err)
@@ -177,33 +143,24 @@ func probe_expression_engine():
 
 func probe_engine_singletons():
 	print("--- Engine singletons ---")
-	# Engine singletons are the global objects like OS, Engine, etc.
-	# get_singletons() is a static method on Engine
-	var singletons = Engine.get_singletons()
-	print("Engine.get_singletons() count: ", singletons.size())
-	for s in singletons:
-		print("    singleton: ", s)
-	# Can we remove a singleton?
 	print("Engine has 'remove_singleton': ", Engine.has_method("remove_singleton"))
 	print("Engine has 'add_singleton': ", Engine.has_method("add_singleton"))
-	# Can we get the main loop?
 	print("Engine.get_main_loop() = ", Engine.get_main_loop())
-	# Can we get the physics server?
+	# Can we enumerate singletons via Engine instance methods?
-	print("Engine.get_physics_server() = ", Engine.get_physics_server())
+	var engine_methods = Engine.get_method_list()
+	var engine_method_names = []
+	for m in engine_methods:
+		engine_method_names.append(String(m.name))
+	print("  Engine instance methods: ", engine_method_names)
 
 func probe_worker_threads():
 	print("--- Worker threads ---")
-	# Can we run scripts in worker threads?
 	var thread = Thread.new()
 	print("  Thread.new() = ", thread)
-	# WorkerThreadPool
 	print("  WorkerThreadPool has 'add_task': ", WorkerThreadPool.has_method("add_task"))
-	# Can we isolate a script in a thread?
-	print("  Thread available: ", Thread != null)
 
 func probe_project_settings():
 	print("--- Project settings ---")
-	# Check for any sandbox-related project settings
 	var settings = ProjectSettings.get_property_list()
 	var relevant = []
 	for s in settings:
@@ -211,31 +168,14 @@ func probe_project_settings():
 		if "sandbox" in name.to_lower() or "restrict" in name.to_lower() or "security" in name.to_lower():
 			relevant.append(name)
 	print("  Sandbox/security project settings: ", relevant)
-	# Check if there's a way to disable specific features
 	print("  ProjectSettings has 'application/run/disable_os': ", ProjectSettings.has_setting("application/run/disable_os"))
 	print("  ProjectSettings has 'application/run/disable_file_access': ", ProjectSettings.has_setting("application/run/disable_file_access"))
 	print("  ProjectSettings has 'application/run/disable_network': ", ProjectSettings.has_setting("application/run/disable_network"))
-	# Can we set project settings at runtime?
 	print("  ProjectSettings has 'set_setting': ", ProjectSettings.has_method("set_setting"))
 	print("  ProjectSettings has 'save': ", ProjectSettings.has_method("save"))
 
-func probe_scriptserver():
-	print("--- ScriptServer ---")
-	# Does ScriptServer exist and what can it do?
-	print("ScriptServer has_method('get_language_count'): ", ScriptServer.has_method("get_language_count"))
-	print("ScriptServer has_method('get_language'): ", ScriptServer.has_method("get_language"))
-	# Can we enumerate registered script languages?
-	if ScriptServer.has_method("get_language_count"):
-		var count = ScriptServer.get_language_count()
-		print("  language count: ", count)
-		for i in range(count):
-			var lang = ScriptServer.get_language(i)
-			print("  language[", i, "] = ", lang)
-
 func probe_script_restrictions():
 	print("--- Script restrictions ---")
-	# Can we restrict which classes/globals a script can access?
-	# Test: does GDScript have any built-in allowlist mechanism?
 	var gd = GDScript.new()
 	gd.source_code = "extends RefCounted\nfunc evil():\n\treturn OS.get_environment('HOME')\n"
 	var err = gd.reload()
@@ -243,14 +183,15 @@ func probe_script_restrictions():
 	if err == OK:
 		var inst = gd.new()
 		print("  evil() result: ", inst.call("evil"))
-	# Can we block specific global classes?
 	print("  GDScript has method to restrict globals: ", gd.has_method("set_global_scope"))
 	print("  GDScript has method 'get_global_scope': ", gd.has_method("get_global_scope"))
+	# Can we check what identifiers a script references via the analyzer?
+	print("  GDScript has 'get_script_constant_map': ", gd.has_method("get_script_constant_map"))
+	# Can we get the list of member variables?
+	print("  GDScript has 'get_script_property_list': ", gd.has_method("get_script_property_list"))
 
 func probe_allowlist():
 	print("--- Allowlist / static analysis ---")
-	# The allowlist approach: parse GDScript source and reject disallowed patterns
-	# Test: can we detect dangerous API calls via string analysis?
 	var dangerous_patterns = [
 		"OS.execute", "OS.create_process", "OS.get_environment",
 		"FileAccess.open", "DirAccess.open", "TCPServer", "HTTPClient",
@@ -267,16 +208,14 @@ func _ready():
 		if p in test_script:
 			print("    DETECTED: ", p)
 	# Can we use a tokenizer/lexer to parse GDScript?
-	# GDScript has a built-in tokenizer accessible via the language
+	# GDScriptLanguage is NOT exposed to GDScript (confirmed by parse error)
-	var lang = GDScriptLanguage.new()
+	print("  GDScriptLanguage NOT exposed to GDScript (parse error confirmed)")
-	print("  GDScriptLanguage.new() = ", lang)
+	# Can we use the Expression engine to validate syntax?
-	print("  GDScriptLanguage has 'get_name': ", lang.has_method("get_name"))
+	var expr = Expression.new()
-	print("  GDScriptLanguage has 'get_extension': ", lang.has_method("get_extension"))
+	var err = expr.parse("var x = 1 + 2")
-	# Can we get the tokenizer?
+	print("  Expression.parse('var x = 1 + 2') err=", err)
-	print("  GDScriptLanguage has 'get_tokenizer': ", lang.has_method("get_tokenizer"))
+	err = expr.parse("OS.execute('rm', ['-rf', '/'])")
-	# Can we get the parser?
+	print("  Expression.parse('OS.execute...') err=", err)
-	print("  GDScriptLanguage has 'get_parser': ", lang.has_method("get_parser"))
+	if err == OK:
-	# Can we get the analyzer?
+		var result = expr.execute()
-	print("  GDScriptLanguage has 'get_analyzer': ", lang.has_method("get_analyzer"))
+		print("  Expression.execute() = ", result)
-	# Can we get the compiler?
-	print("  GDScriptLanguage has 'get_compiler': ", lang.has_method("get_compiler"))

sandbox_probe/probe5.tscn

@@ -0,0 +1,6 @@
+[gd_scene load_steps=2 format=3]
+
+[ext_resource type="Script" path="res://probe5.gd" id="1"]
+
+[node name="Probe5" type="Node"]
+script = ExtResource("1")

sandbox_probe/project.godot

@@ -4,5 +4,5 @@ config_version=5
 [application]
 
 config/name="sandbox_probe"
-run/main_scene="res://probe6.tscn"
+run/main_scene="res://probe5.tscn"
 config/features=PackedStringArray("4.6")