AP_Scripting: add require with sandbox inheritence

libraries/AP_Scripting/AP_Scripting.h

@@ -94,6 +94,8 @@ public:
     // PWMSource storage
     uint8_t num_pwm_source;
     AP_HAL::PWMSource *_pwm_source[SCRIPTING_MAX_NUM_PWM_SOURCE];
+    int get_current_ref() { return current_ref; }
+    void set_current_ref(int ref) { current_ref = ref; }
 
 private:
 
@@ -116,7 +118,7 @@ private:
     bool _stop; // true if scripts should be stopped
 
     static AP_Scripting *_singleton;
-
+    int current_ref;
 };
 
 namespace AP {

libraries/AP_Scripting/lua/src/lbaselib.c

@@ -501,6 +501,13 @@ LUAMOD_API int luaopen_base (lua_State *L) {
 
 LUAMOD_API int luaopen_base_sandbox(lua_State *L) {
   luaL_setfuncs(L, base_funcs, 0);
+  // for debugging what has been loaded
+  // lua_pushvalue(L, -1);
+  // lua_setfield(L, -2, "_Sandbox");
+  // lua_pushglobaltable(L);
+  // lua_pushvalue(L, -1);
+  // lua_setfield(L, -3, "_G");
+  // lua_pop(L, 1);
+
   return 1;
 }
-

libraries/AP_Scripting/lua/src/loadlib.c

@@ -74,7 +74,9 @@ static const int CLIBS = 0;
 /*
 ** unload library 'lib'
 */
+#if !defined(ARDUPILOT_BUILD)
 static void lsys_unloadlib (void *lib);
+#endif
 
 /*
 ** load C library in file 'path'. If 'seeglb', load with all names in
@@ -227,10 +229,11 @@ static lua_CFunction lsys_sym (lua_State *L, void *lib, const char *sym) {
 
 #define DLMSG	"dynamic libraries not enabled; check your Lua installation"
 
-
+#if !defined(ARDUPILOT_BUILD)
 static void lsys_unloadlib (void *lib) {
   (void)(lib);  /* not used */
 }
+#endif
 
 
 static void *lsys_load (lua_State *L, const char *path, int seeglb) {
@@ -342,6 +345,7 @@ static void addtoclib (lua_State *L, const char *path, void *plib) {
 ** __gc tag method for CLIBS table: calls 'lsys_unloadlib' for all lib
 ** handles in list CLIBS
 */
+#if !defined(ARDUPILOT_BUILD)
 static int gctm (lua_State *L) {
   lua_Integer n = luaL_len(L, 1);
   for (; n >= 1; n--) {  /* for each handle, in reverse order */
@@ -351,6 +355,7 @@ static int gctm (lua_State *L) {
   }
   return 0;
 }
+#endif
 
 
 
@@ -509,6 +514,7 @@ static int searcher_Lua (lua_State *L) {
 ** fails, it also tries "luaopen_Y".) If there is no ignore mark,
 ** look for a function named "luaopen_modname".
 */
+#if !defined(ARDUPILOT_BUILD)
 static int loadfunc (lua_State *L, const char *filename, const char *modname) {
   const char *openfunc;
   const char *mark;
@@ -564,12 +570,30 @@ static int searcher_preload (lua_State *L) {
     lua_pushfstring(L, "\n\tno field package.preload['%s']", name);
   return 1;
 }
-
+#endif
 
 static void findloader (lua_State *L, const char *name) {
-  int i;
   luaL_Buffer msg;  /* to build error message */
   luaL_buffinit(L, &msg);
+  lua_pushstring(L, name);
+#if defined(ARDUPILOT_BUILD)
+  // since we only use lua modules there's no point
+  // in searching for C or other types of modules
+  // so we just call the lua searcher
+  searcher_Lua(L);
+  if (lua_isfunction(L, -2)) {  /* module loader found? */
+    return;  /* module loader already on stack */
+  } else if (lua_isstring(L, -2)) {  /* searcher returned error message? */
+    lua_pop(L, 1);  /* remove extra return */
+    luaL_addvalue(&msg);  /* concatenate error message */
+  } else {
+    lua_pop(L, 2);  /* remove both returns */
+  }
+  // module not found
+  lua_pop(L, 1);  /* remove nil */
+  luaL_pushresult(&msg);  /* create error message */
+  luaL_error(L, "module '%s' not found:%s", name, lua_tostring(L, -1));
+#else
   /* push 'package.searchers' to index 3 in the stack */
   if (lua_getfield(L, lua_upvalueindex(1), "searchers") != LUA_TTABLE)
     luaL_error(L, "'package.searchers' must be a table");
@@ -591,28 +615,33 @@ static void findloader (lua_State *L, const char *name) {
     else
       lua_pop(L, 2);  /* remove both returns */
   }
+#endif
 }
 
 
 static int ll_require (lua_State *L) {
   const char *name = luaL_checkstring(L, 1);
-  lua_settop(L, 1);  /* LOADED table will be at index 2 */
-  lua_getfield(L, LUA_REGISTRYINDEX, LUA_LOADED_TABLE);
-  lua_getfield(L, 2, name);  /* LOADED[name] */
+  lua_settop(L, 1);
+  lua_rawgeti(L, LUA_REGISTRYINDEX, lua_get_current_ref()); /* get the current script */
+  lua_getupvalue(L, 2, 1); /* get the environment of the script */
+  lua_getfield(L, 3, LUA_LOADED_TABLE); /* get _LOADED */
+  lua_getfield(L, 4, name);  /* LOADED[name] */
   if (lua_toboolean(L, -1))  /* is it there? */
     return 1;  /* package is already loaded */
   /* else must load package */
   lua_pop(L, 1);  /* remove 'getfield' result */
   findloader(L, name);
+  lua_pushvalue(L, 3); /* push current script's environment */
+  lua_setupvalue(L, -3, 1); /* set the environment of the module */
   lua_pushstring(L, name);  /* pass name as argument to module loader */
   lua_insert(L, -2);  /* name is 1st argument (before search data) */
   lua_call(L, 2, 1);  /* run loader to load module */
   if (!lua_isnil(L, -1))  /* non-nil return? */
-    lua_setfield(L, 2, name);  /* LOADED[name] = returned value */
-  if (lua_getfield(L, 2, name) == LUA_TNIL) {   /* module set no value? */
+    lua_setfield(L, 4, name);  /* LOADED[name] = returned value */
+  if (lua_getfield(L, 4, name) == LUA_TNIL) {   /* module set no value? */
     lua_pushboolean(L, 1);  /* use true as result */
     lua_pushvalue(L, -1);  /* extra copy to be returned */
-    lua_setfield(L, 2, name);  /* LOADED[name] = true */
+    lua_setfield(L, 4, name);  /* LOADED[name] = true */
   }
   return 1;
 }
@@ -713,9 +742,9 @@ static const luaL_Reg pk_funcs[] = {
 #endif
   /* placeholders */
   {"preload", NULL},
-  {"cpath", NULL},
+  // {"cpath", NULL},
   {"path", NULL},
-  {"searchers", NULL},
+  // {"searchers", NULL},
   {"loaded", NULL},
   {NULL, NULL}
 };
@@ -729,7 +758,7 @@ static const luaL_Reg ll_funcs[] = {
   {NULL, NULL}
 };
 
-
+#if !defined(ARDUPILOT_BUILD)
 static void createsearcherstable (lua_State *L) {
   static const lua_CFunction searchers[] =
     {searcher_preload, searcher_Lua, searcher_C, searcher_Croot, NULL};
@@ -762,29 +791,31 @@ static void createclibstable (lua_State *L) {
   lua_setmetatable(L, -2);
   lua_rawsetp(L, LUA_REGISTRYINDEX, &CLIBS);  /* set CLIBS table in registry */
 }
-
+#endif
 
 LUAMOD_API int luaopen_package (lua_State *L) {
-  createclibstable(L);
+  // createclibstable(L);
   luaL_newlib(L, pk_funcs);  /* create 'package' table */
-  createsearcherstable(L);
+  // createsearcherstable(L);
   /* set paths */
   setpath(L, "path", LUA_PATH_VAR, LUA_PATH_DEFAULT);
-  setpath(L, "cpath", LUA_CPATH_VAR, LUA_CPATH_DEFAULT);
+  // setpath(L, "cpath", LUA_CPATH_VAR, LUA_CPATH_DEFAULT);
   /* store config information */
   lua_pushliteral(L, LUA_DIRSEP "\n" LUA_PATH_SEP "\n" LUA_PATH_MARK "\n"
                      LUA_EXEC_DIR "\n" LUA_IGMARK "\n");
   lua_setfield(L, -2, "config");
   /* set field 'loaded' */
-  luaL_getsubtable(L, LUA_REGISTRYINDEX, LUA_LOADED_TABLE);
+  luaL_getsubtable(L, -3, LUA_LOADED_TABLE);
   lua_setfield(L, -2, "loaded");
+
   /* set field 'preload' */
-  luaL_getsubtable(L, LUA_REGISTRYINDEX, LUA_PRELOAD_TABLE);
+  luaL_getsubtable(L, -3, LUA_PRELOAD_TABLE);
   lua_setfield(L, -2, "preload");
-  lua_pushglobaltable(L);
+
+  lua_pushvalue(L, -3);
   lua_pushvalue(L, -2);  /* set 'package' as upvalue for next lib */
   luaL_setfuncs(L, ll_funcs, 1);  /* open lib into global table */
-  lua_pop(L, 1);  /* pop global table */
+  lua_pop(L, 1);
+
   return 1;  /* return 'package' table */
 }
-

libraries/AP_Scripting/lua/src/luaconf.h

@@ -17,6 +17,7 @@
 #ifndef LUA_SUPPORT_LOAD_BINARY
 #define LUA_SUPPORT_LOAD_BINARY 0
 #endif
+#include <AP_Scripting/lua_common_defs.h>
 
 /*
 ** ===================================================================
@@ -207,11 +208,10 @@
 #else			/* }{ */
 
 #define LUA_ROOT	"/usr/local/"
-#define LUA_LDIR	LUA_ROOT "share/lua/" LUA_VDIR "/"
+#define LUA_LDIR	SCRIPTING_DIRECTORY "/modules/"
 #define LUA_CDIR	LUA_ROOT "lib/lua/" LUA_VDIR "/"
 #define LUA_PATH_DEFAULT  \
 		LUA_LDIR"?.lua;"  LUA_LDIR"?/init.lua;" \
-		LUA_CDIR"?.lua;"  LUA_CDIR"?/init.lua;" \
 		"./?.lua;" "./?/init.lua"
 #define LUA_CPATH_DEFAULT \
 		LUA_CDIR"?.so;" LUA_CDIR"loadall.so;" "./?.so"

libraries/AP_Scripting/lua_bindings.cpp

@@ -572,3 +572,9 @@ int lua_get_PWMSource(lua_State *L) {
 
     return 1;
 }
+
+int lua_get_current_ref()
+{
+    auto *scripting = AP::scripting();
+    return scripting->get_current_ref();
+}

libraries/AP_Scripting/lua_common_defs.h

@@ -0,0 +1,29 @@
+#pragma once
+
+#include <AP_HAL/AP_HAL_Boards.h>
+
+#ifndef REPL_DIRECTORY
+  #if HAL_OS_FATFS_IO
+    #define REPL_DIRECTORY "/APM/repl"
+  #else
+    #define REPL_DIRECTORY "./repl"
+  #endif //HAL_OS_FATFS_IO
+#endif // REPL_DIRECTORY
+
+#ifndef SCRIPTING_DIRECTORY
+  #if HAL_OS_FATFS_IO
+    #define SCRIPTING_DIRECTORY "/APM/scripts"
+  #else
+    #define SCRIPTING_DIRECTORY "./scripts"
+  #endif //HAL_OS_FATFS_IO
+#endif // SCRIPTING_DIRECTORY
+
+#ifndef REPL_IN
+  #define REPL_IN REPL_DIRECTORY "/in"
+#endif // REPL_IN
+
+#ifndef REPL_OUT
+  #define REPL_OUT REPL_DIRECTORY "/out"
+#endif // REPL_OUT
+
+int lua_get_current_ref();

libraries/AP_Scripting/lua_scripts.cpp

@@ -23,6 +23,7 @@
 #define DISABLE_INTERRUPTS_FOR_SCRIPT_RUN 0
 
 extern const AP_HAL::HAL& hal;
+#define ENABLE_DEBUG_MODULE 0
 
 bool lua_scripts::overtime;
 jmp_buf lua_scripts::panic_jmp;
@@ -198,6 +199,12 @@ lua_scripts::script_info *lua_scripts::load_script(lua_State *L, char *filename)
 void lua_scripts::create_sandbox(lua_State *L) {
     lua_newtable(L);
     luaopen_base_sandbox(L);
+
+#if ENABLE_DEBUG_MODULE
+    lua_pushstring(L, "debug");
+    luaopen_debug(L);
+    lua_settable(L, -3);
+#endif
     lua_pushstring(L, "math");
     luaopen_math(L);
     lua_settable(L, -3);
@@ -213,8 +220,11 @@ void lua_scripts::create_sandbox(lua_State *L) {
     lua_pushstring(L, "utf8");
     luaopen_utf8(L);
     lua_settable(L, -3);
-    load_generated_sandbox(L);
+    lua_pushstring(L, "package");
+    luaopen_package(L);
+    lua_settable(L, -3);
 
+    load_generated_sandbox(L);
 }
 
 void lua_scripts::load_all_scripts_in_dir(lua_State *L, const char *dirname) {
@@ -294,6 +304,7 @@ void lua_scripts::run_next_script(lua_State *L) {
 
     // pop the function to the top of the stack
     lua_rawgeti(L, LUA_REGISTRYINDEX, script->lua_ref);
+    AP::scripting()->set_current_ref(script->lua_ref);
 
     if(lua_pcall(L, 0, LUA_MULTRET, 0)) {
         if (overtime) {

libraries/AP_Scripting/lua_scripts.h

@@ -23,33 +23,10 @@
 #include <GCS_MAVLink/GCS_MAVLink.h>
 #include <AP_HAL/Semaphores.h>
 #include <AP_Common/MultiHeap.h>
+#include "lua_common_defs.h"
 
 #include "lua/src/lua.hpp"
 
-#ifndef REPL_DIRECTORY
-  #if HAL_OS_FATFS_IO
-    #define REPL_DIRECTORY "/APM/repl"
-  #else
-    #define REPL_DIRECTORY "./repl"
-  #endif //HAL_OS_FATFS_IO
-#endif // REPL_DIRECTORY
-
-#ifndef SCRIPTING_DIRECTORY
-  #if HAL_OS_FATFS_IO
-    #define SCRIPTING_DIRECTORY "/APM/scripts"
-  #else
-    #define SCRIPTING_DIRECTORY "./scripts"
-  #endif //HAL_OS_FATFS_IO
-#endif // SCRIPTING_DIRECTORY
-
-#ifndef REPL_IN
-  #define REPL_IN REPL_DIRECTORY "/in"
-#endif // REPL_IN
-
-#ifndef REPL_OUT
-  #define REPL_OUT REPL_DIRECTORY "/out"
-#endif // REPL_OUT
-
 class lua_scripts
 {
 public:
@@ -78,7 +55,6 @@ public:
 private:
 
     void create_sandbox(lua_State *L);
-
     void repl_cleanup(void);
 
     typedef struct script_info {
@@ -143,6 +119,7 @@ private:
     static HAL_Semaphore error_msg_buf_sem;
     static uint8_t print_error_count;
     static uint32_t last_print_ms;
+    int current_ref;
 
 public:
     // must be static for use in atpanic, public to allow bindings to issue none fatal warnings