gumjs: Add findSymbolByName()/getSymbolByName()

Provide direct, native lookups for symbols by name instead of enumerating
all symbols and filtering them in JavaScript. On ELF-based backends,
we can potentially leverage binary search for faster performance.

bindings/gumjs/gumquickmodule.c

@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2020-2023 Ole André Vadla Ravnås <[email protected]>
+ * Copyright (C) 2020-2024 Ole André Vadla Ravnås <[email protected]>
  *
  * Licence: wxWindows Library Licence, Version 3.1
  */
@@ -51,6 +51,7 @@ static gboolean gum_emit_dependency (const GumDependencyDetails * details,
     GumQuickMatchContext * mc);
 GUMJS_DECLARE_FUNCTION (gumjs_module_find_base_address)
 GUMJS_DECLARE_FUNCTION (gumjs_module_find_export_by_name)
+GUMJS_DECLARE_FUNCTION (gumjs_module_find_symbol_by_name)
 
 GUMJS_DECLARE_CONSTRUCTOR (gumjs_module_map_construct)
 GUMJS_DECLARE_FINALIZER (gumjs_module_map_finalize)
@@ -84,6 +85,7 @@ static const JSCFunctionListEntry gumjs_module_entries[] =
       gumjs_module_enumerate_dependencies),
   JS_CFUNC_DEF ("findBaseAddress", 0, gumjs_module_find_base_address),
   JS_CFUNC_DEF ("findExportByName", 0, gumjs_module_find_export_by_name),
+  JS_CFUNC_DEF ("findSymbolByName", 0, gumjs_module_find_symbol_by_name),
 };
 
 static const JSClassDef gumjs_module_map_def =
@@ -599,6 +601,27 @@ GUMJS_DEFINE_FUNCTION (gumjs_module_find_export_by_name)
   return _gum_quick_native_pointer_new (ctx, GSIZE_TO_POINTER (address), core);
 }
 
+GUMJS_DEFINE_FUNCTION (gumjs_module_find_symbol_by_name)
+{
+  const gchar * module_name, * symbol_name;
+  GumQuickScope scope = GUM_QUICK_SCOPE_INIT (core);
+  GumAddress address;
+
+  if (!_gum_quick_args_parse (args, "s?s", &module_name, &symbol_name))
+    return JS_EXCEPTION;
+
+  _gum_quick_scope_suspend (&scope);
+
+  address = gum_module_find_symbol_by_name (module_name, symbol_name);
+
+  _gum_quick_scope_resume (&scope);
+
+  if (address == 0)
+    return JS_NULL;
+
+  return _gum_quick_native_pointer_new (ctx, GSIZE_TO_POINTER (address), core);
+}
+
 static gboolean
 gum_quick_module_map_get (JSContext * ctx,
                           JSValueConst val,

bindings/gumjs/gumv8module.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2010-2023 Ole André Vadla Ravnås <[email protected]>
+ * Copyright (C) 2010-2024 Ole André Vadla Ravnås <[email protected]>
  *
  * Licence: wxWindows Library Licence, Version 3.1
  */
@@ -85,6 +85,7 @@ static gboolean gum_emit_dependency (const GumDependencyDetails * details,
     GumV8MatchContext<GumV8Module> * mc);
 GUMJS_DECLARE_FUNCTION (gumjs_module_find_base_address)
 GUMJS_DECLARE_FUNCTION (gumjs_module_find_export_by_name)
+GUMJS_DECLARE_FUNCTION (gumjs_module_find_symbol_by_name)
 
 GUMJS_DECLARE_CONSTRUCTOR (gumjs_module_map_construct)
 GUMJS_DECLARE_GETTER (gumjs_module_map_get_handle)
@@ -117,6 +118,7 @@ static const GumV8Function gumjs_module_static_functions[] =
   { "_enumerateDependencies", gumjs_module_enumerate_dependencies },
   { "findBaseAddress", gumjs_module_find_base_address },
   { "findExportByName", gumjs_module_find_export_by_name },
+  { "findSymbolByName", gumjs_module_find_symbol_by_name },
 
   { NULL, NULL }
 };
@@ -630,6 +632,33 @@ GUMJS_DEFINE_FUNCTION (gumjs_module_find_export_by_name)
   g_free (symbol_name);
 }
 
+GUMJS_DEFINE_FUNCTION (gumjs_module_find_symbol_by_name)
+{
+  gchar * module_name, * symbol_name;
+  if (!_gum_v8_args_parse (args, "s?s", &module_name, &symbol_name))
+    return;
+
+  GumAddress address;
+  {
+    ScriptUnlocker unlocker (core);
+
+    address = gum_module_find_symbol_by_name (module_name, symbol_name);
+  }
+
+  if (address != 0)
+  {
+    info.GetReturnValue ().Set (
+        _gum_v8_native_pointer_new (GSIZE_TO_POINTER (address), core));
+  }
+  else
+  {
+    info.GetReturnValue ().SetNull ();
+  }
+
+  g_free (module_name);
+  g_free (symbol_name);
+}
+
 GUMJS_DEFINE_CONSTRUCTOR (gumjs_module_map_construct)
 {
   if (!info.IsConstructCall ())

bindings/gumjs/runtime/core.js

@@ -314,6 +314,17 @@ Object.defineProperties(Module, {
       return address;
     }
   },
+  getSymbolByName: {
+    enumerable: true,
+    value: function (moduleName, symbolName) {
+      const address = Module.findSymbolByName(moduleName, symbolName);
+      if (address === null) {
+        const prefix = (moduleName !== null) ? (moduleName + ': ') : '';
+        throw new Error(prefix + "unable to find symbol '" + symbolName + "'");
+      }
+      return address;
+    }
+  },
 });
 
 Object.defineProperties(Module.prototype, {
@@ -365,6 +376,18 @@ Object.defineProperties(Module.prototype, {
       return Module.getExportByName(this.path, exportName);
     }
   },
+  findSymbolByName: {
+    enumerable: true,
+    value: function (symbolName) {
+      return Module.findSymbolByName(this.path, symbolName);
+    }
+  },
+  getSymbolByName: {
+    enumerable: true,
+    value: function (symbolName) {
+      return Module.getSymbolByName(this.path, symbolName);
+    }
+  },
 });
 
 Object.defineProperties(ModuleMap.prototype, {

tests/gumjs/script.c

@@ -256,6 +256,7 @@ TESTLIST_BEGIN (script)
     TESTENTRY (module_dependencies_can_be_enumerated)
     TESTENTRY (module_base_address_can_be_found)
     TESTENTRY (module_export_can_be_found_by_name)
+    TESTENTRY (module_symbol_can_be_found_by_name)
     TESTENTRY (module_can_be_loaded)
     TESTENTRY (module_can_be_forcibly_initialized)
   TESTGROUP_END ()
@@ -5872,6 +5873,46 @@ TESTCASE (module_export_can_be_found_by_name)
 #endif
 }
 
+TESTCASE (module_symbol_can_be_found_by_name)
+{
+  if (!g_test_slow ())
+  {
+    g_print ("<skipping, run in slow mode> ");
+    return;
+  }
+
+  COMPILE_AND_LOAD_SCRIPT (
+      "const sysModuleName = '%s';"
+
+      "const allSymbols = Process.getModuleByName(sysModuleName).enumerateSymbols();"
+      "const sysModuleExport = allSymbols.find(s => !s.address.isNull()).name;"
+
+      "const badModuleName = 'nope_' + sysModuleName;"
+      "const badModuleExport = sysModuleExport + '_does_not_exist';"
+
+      "const impl = Module.findSymbolByName(sysModuleName, sysModuleExport);"
+      "send(impl !== null);"
+
+      "send(Module.findSymbolByName(badModuleName, badModuleExport) === null);"
+
+      "try {"
+          "send(Module.getSymbolByName(sysModuleName, sysModuleExport)"
+              ".equals(impl));"
+
+          "Module.getSymbolByName(badModuleName, badModuleExport);"
+          "send('should not get here');"
+      "} catch (e) {"
+          "send(/unable to find symbol/.test(e.message));"
+      "}",
+      SYSTEM_MODULE_NAME);
+
+  EXPECT_SEND_MESSAGE_WITH ("true");
+  EXPECT_SEND_MESSAGE_WITH ("true");
+
+  EXPECT_SEND_MESSAGE_WITH ("true");
+  EXPECT_SEND_MESSAGE_WITH ("true");
+}
+
 TESTCASE (module_can_be_loaded)
 {
   COMPILE_AND_LOAD_SCRIPT (