src/script/cpp_api/s_security.cpp

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2016-05-22
* DB::loadBlock copy removal & DB backend cleanup Loic Blot 2016-05-17
* Remove expensive copy of ContentFeatures gregorycu 2016-03-30
* Liquid flow: Prevent water spreading on ignore paramat 2016-01-20
* Liquids: Flow into and destroy 'floodable' nodes paramat 2016-01-07
* Rename macros with two leading underscores ShadowNinja 2015-10-14
* Use warningstream for log messages with WARNING ShadowNinja 2015-10-14
* Add emerge completion callback mechanism kwolekr 2015-10-04
* Define and use limit constants for Irrlicht fixed-width types kwolekr 2015-10-04
* Add /emergeblocks command and core.emerge_area() Lua API kwolekr 2015-09-23
* Fix segfault caused by a8e238ed06ee8285ed4459e9deda3117419837f6 Perttu Ahola 2015-08-13
* Add count based unload limit for mapblocks est31 2015-08-13
* Add map limit config option rubenwardy 2015-08-02
* Record MapBlock modification reasons as flags instead of strings kwolekr 2015-05-17
* Ensure that Map::findNodesWithMetadata() reports nodes strictly within the no... kwolekr 2015-05-08
* Add core.find_nodes_with_meta() script API kwolekr 2015-05-05
* Move globals from main.cpp to more sane locations Craig Robbins 2015-04-01
* Respect game mapgen flags and save world noise params ngosang 2015-03-07
* For usages of assert() that are meant to persist in Release builds (when NDEB... Craig Robbins 2015-03-07
* Don't start a server for map migration ShadowNinja 2015-03-06
* Clean up database API and save the local map on an interval ShadowNinja 2015-03-06
* ABMHandler and player_collisions use sequential read/write. Switch from std::... Loic Blot 2015-03-04
* Fix unused (and so, broken) enable_rollback_recording. This option must be re... Loic Blot 2015-02-18
* Replace std::list by std::vector into ClientMap::updateDrawList, Map::timerUp... Loic Blot 2015-02-17
* Replace std::list by std::vector into timerUpdate calls Loic Blot 2015-02-17
* Replace std::list by std::vector into ServerMap::listAllLoadableBlocks Server... Loic Blot 2015-02-17
* Fix missing map_meta.txt error when creating new worlds kwolekr 2015-01-27
* Fix all warnings and remove -Wno-unused-but-set cflag kwolekr 2015-01-18
* Water fixes gregorycu 2015-01-18
* Create empty default constructor for MapNode Craig Robbins 2015-01-18
* Add ability to delete MapBlocks from map kwolekr 2015-01-15
* Change UniqueQueue to use a queue and a set. unknown 2015-01-15
* Fix use of uninitialized data Craig Robbins 2015-01-14
/*
Minetest
Copyright (C) 2013 celeron55, Perttu Ahola <celeron55@gmail.com>

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along
with this program; if not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/

#include "cpp_api/s_security.h"

#include "filesys.h"
#include "porting.h"
#include "server.h"
#include "client/client.h"
#include "settings.h"

#include <cerrno>
#include <string>
#include <iostream>


#define SECURE_API(lib, name) \
	lua_pushcfunction(L, sl_##lib##_##name); \
	lua_setfield(L, -2, #name);


static inline void copy_safe(lua_State *L, const char *list[], unsigned len, int from=-2, int to=-1)
{
	if (from < 0) from = lua_gettop(L) + from + 1;
	if (to   < 0) to   = lua_gettop(L) + to   + 1;
	for (unsigned i = 0; i < (len / sizeof(list[0])); i++) {
		lua_getfield(L, from, list[i]);
		lua_setfield(L, to,   list[i]);
	}
}

// Pushes the original version of a library function on the stack, from the old version
static inline void push_original(lua_State *L, const char *lib, const char *func)
{
	lua_rawgeti(L, LUA_REGISTRYINDEX, CUSTOM_RIDX_GLOBALS_BACKUP);
	lua_getfield(L, -1, lib);
	lua_remove(L, -2);  // Remove globals_backup
	lua_getfield(L, -1, func);
	lua_remove(L, -2);  // Remove lib
}


void ScriptApiSecurity::initializeSecurity()
{
	static const char *whitelist[] = {
		"assert",
		"core",
		"collectgarbage",
		"DIR_DELIM",
		"error",
		"getfenv",
		"getmetatable",
		"ipairs",
		"next",
		"pairs",
		"pcall",
		"print",
		"rawequal",
		"rawget",
		"rawset",
		"select",
		"setfenv",
		"setmetatable",
		"tonumber",
		"tostring",
		"type",
		"unpack",
		"_VERSION",
		"xpcall",
		// Completely safe libraries
		"coroutine",
		"string",
		"table",
		"math",
	};
	static const char *io_whitelist[] = {
		"close",
		"flush",
		"read",
		"type",
		"write",
	};
	static const char *os_whitelist[] = {
		"clock",
		"date",
		"difftime",
		"getenv",
		"setlocale",
		"time",
		"tmpname",
	};
	static const char *debug_whitelist[] = {
		"gethook",
		"traceback",
		"getinfo",
		"getmetatable",
		"setupvalue",
		"setmetatable",
		"upvalueid",
		"sethook",
		"debug",
		"setlocal",
	};
	static const char *package_whitelist[] = {
		"config",
		"cpath",
		"path",
		"searchpath",
	};
#if USE_LUAJIT
	static const char *jit_whitelist[] = {
		"arch",
		"flush",
		"off",
		"on",
		"opt",
		"os",
		"status",
		"version",
		"version_num",
	};
#endif
	m_secure = true;

	lua_State *L = getStack();

	// Backup globals to the registry
	lua_getglobal(L, "_G");
	lua_rawseti(L, LUA_REGISTRYINDEX, CUSTOM_RIDX_GLOBALS_BACKUP);

	// Replace the global environment with an empty one
	int thread = getThread(L);
	createEmptyEnv(L);
	setLuaEnv(L, thread);

	// Get old globals
	lua_rawgeti(L, LUA_REGISTRYINDEX, CUSTOM_RIDX_GLOBALS_BACKUP);
	int old_globals = lua_gettop(L);


	// Copy safe base functions
	lua_getglobal(L, "_G");
	copy_safe(L, whitelist, sizeof(whitelist));

	// And replace unsafe ones
	SECURE_API(g, dofile);
	SECURE_API(g, load);
	SECURE_API(g, loadfile);
	SECURE_API(g, loadstring);
	SECURE_API(g, require);
	lua_pop(L, 1);


	// Copy safe IO functions
	lua_getfield(L, old_globals, "io");
	lua_newtable(L);
	copy_safe(L, io_whitelist, sizeof(io_whitelist));

	// And replace unsafe ones
	SECURE_API(io, open);
	SECURE_API(io, input);
	SECURE_API(io, output);
	SECURE_API(io, lines);

	lua_setglobal(L, "io");
	lua_pop(L, 1);  // Pop old IO


	// Copy safe OS functions
	lua_getfield(L, old_globals, "os");
	lua_newtable(L);
	copy_safe(L, os_whitelist, sizeof(os_whitelist));

	// And replace unsafe ones
	SECURE_API(os, remove);
	SECURE_API(os, rename);

	lua_setglobal(L, "os");
	lua_pop(L, 1);  // Pop old OS


	// Copy safe debug functions
	lua_getfield(L, old_globals, "debug");
	lua_newtable(L);
	copy_safe(L, debug_whitelist, sizeof(debug_whitelist));
	lua_setglobal(L, "debug");
	lua_pop(L, 1);  // Pop old debug


	// Copy safe package fields
	lua_getfield(L, old_globals, "package");
	lua_newtable(L);
	copy_safe(L, package_whitelist, sizeof(package_whitelist));
	lua_setglobal(L, "package");
	lua_pop(L, 1);  // Pop old package

#if USE_LUAJIT
	// Copy safe jit functions, if they exist
	lua_getfield(L, -1, "jit");
	if (!lua_isnil(L, -1)) {
		lua_newtable(L);
		copy_safe(L, jit_whitelist, sizeof(jit_whitelist));
		lua_setglobal(L, "jit");
	}
	lua_pop(L, 1);  // Pop old jit
#endif

	lua_pop(L, 1); // Pop globals_backup
}

void ScriptApiSecurity::initializeSecurityClient()
{
	static const char *whitelist[] = {
		"assert",
		"core",
		"collectgarbage",
		"DIR_DELIM",
		"error",
		"getfenv",
		"ipairs",
		"next",
		"pairs",
		"pcall",
		"print",
		"rawequal",
		"rawget",
		"rawset",
		"select",
		"setfenv",
		// getmetatable can be used to escape the sandbox
		"setmetatable",
		"tonumber",
		"tostring",
		"type",
		"unpack",
		"_VERSION",
		"xpcall",
		// Completely safe libraries
		"coroutine",
		"string",
		"table",
		"math",
	};
	static const char *os_whitelist[] = {
		"clock",
		"date",
		"difftime",
		"time"
	};
	static const char *debug_whitelist[] = {
		"getinfo",
		"traceback"
	};

#if USE_LUAJIT
	static const char *jit_whitelist[] = {
		"arch",
		"flush",
		"off",
		"on",
		"opt",
		"os",
		"status",
		"version",
		"version_num",
	};
#endif

	m_secure = true;

	lua_State *L = getStack();
	int thread = getThread(L);

	// create an empty environment
	createEmptyEnv(L);

	// Copy safe base functions
	lua_getglobal(L, "_G");
	lua_getfield(L, -2, "_G");
	copy_safe(L, whitelist, sizeof(whitelist));

	// And replace unsafe ones
	SECURE_API(g, dofile);
	SECURE_API(g, load);
	SECURE_API(g, loadfile);
	SECURE_API(g, loadstring);
	SECURE_API(g, require);
	lua_pop(L, 2);


	// Copy safe OS functions
	lua_getglobal(L, "os");
	lua_newtable(L);
	copy_safe(L, os_whitelist, sizeof(os_whitelist));
	lua_setfield(L, -3, "os");
	lua_pop(L, 1);  // Pop old OS


	// Copy safe debug functions
	lua_getglobal(L, "debug");
	lua_newtable(L);
	copy_safe(L, debug_whitelist, sizeof(debug_whitelist));
	lua_setfield(L, -3, "debug");
	lua_pop(L, 1);  // Pop old debug

#if USE_LUAJIT
	// Copy safe jit functions, if they exist
	lua_getglobal(L, "jit");
	lua_newtable(L);
	copy_safe(L, jit_whitelist, sizeof(jit_whitelist));
	lua_setfield(L, -3, "jit");
	lua_pop(L, 1);  // Pop old jit
#endif

	// Set the environment to the one we created earlier
	setLuaEnv(L, thread);
}

int ScriptApiSecurity::getThread(lua_State *L)
{
#if LUA_VERSION_NUM <= 501
	int is_main = lua_pushthread(L);  // Push the main thread
	FATAL_ERROR_IF(!is_main, "Security: ScriptApi's Lua state "
		"isn't the main Lua thread!");
	return lua_gettop(L);
#endif
	return 0;
}

void ScriptApiSecurity::createEmptyEnv(lua_State *L)
{
	lua_newtable(L);  // Create new environment
	lua_pushvalue(L, -1);
	lua_setfield(L, -2, "_G");  // Create the _G loop
}

void ScriptApiSecurity::setLuaEnv(lua_State *L, int thread)
{
#if LUA_VERSION_NUM >= 502  // Lua >= 5.2
	// Set the global environment
	lua_rawseti(L, LUA_REGISTRYINDEX, LUA_RIDX_GLOBALS);
#else  // Lua <= 5.1
	// Set the environment of the main thread
	FATAL_ERROR_IF(!lua_setfenv(L, thread), "Security: Unable to set "
		"environment of the main Lua thread!");
	lua_pop(L, 1);  // Pop thread
#endif
}

bool ScriptApiSecurity::isSecure(lua_State *L)
{
	lua_rawgeti(L, LUA_REGISTRYINDEX, CUSTOM_RIDX_GLOBALS_BACKUP);
	bool secure = !lua_isnil(L, -1);
	lua_pop(L, 1);
	return secure;
}

bool ScriptApiSecurity::safeLoadString(lua_State *L, const std::string &code, const char *chunk_name)
{
	if (code.size() > 0 && code[0] == LUA_SIGNATURE[0]) {
		lua_pushliteral(L, "Bytecode prohibited when mod security is enabled.");
		return false;
	}
	if (luaL_loadbuffer(L, code.data(), code.size(), chunk_name))
		return false;
	return true;
}

bool ScriptApiSecurity::safeLoadFile(lua_State *L, const char *path, const char *display_name)
{
	FILE *fp;
	char *chunk_name;
	if (!display_name)
		display_name = path;
	if (!path) {
		fp = stdin;
		chunk_name = const_cast<char *>("=stdin");
	} else {
		fp = fopen(path, "rb");
		if (!fp) {
			lua_pushfstring(L, "%s: %s", path, strerror(errno));
			return false;
		}
		chunk_name = new char[strlen(display_name) + 2];
		chunk_name[0] = '@';
		chunk_name[1] = '\0';
		strcat(chunk_name, display_name);
	}

	size_t start = 0;
	int c = std::getc(fp);
	if (c == '#') {
		// Skip the first line
		while ((c = std::getc(fp)) != EOF && c != '\n') {}
		if (c == '\n')
			std::getc(fp);
		start = std::ftell(fp);
	}

	// Read the file
	int ret = std::fseek(fp, 0, SEEK_END);
	if (ret) {
		lua_pushfstring(L, "%s: %s", path, strerror(errno));
		if (path) {
			std::fclose(fp);
			delete [] chunk_name;
		}
		return false;
	}

	size_t size = std::ftell(fp) - start;
	std::string code(size, '\0');
	ret = std::fseek(fp, start, SEEK_SET);
	if (ret) {
		lua_pushfstring(L, "%s: %s", path, strerror(errno));
		if (path) {
			std::fclose(fp);
			delete [] chunk_name;
		}
		return false;
	}

	size_t num_read = std::fread(&code[0], 1, size, fp);
	if (path)
		std::fclose(fp);
	if (num_read != size) {
		lua_pushliteral(L, "Error reading file to load.");
		if (path)
			delete [] chunk_name;
		return false;
	}

	bool result = safeLoadString(L, code, chunk_name);
	if (path)
		delete [] chunk_name;
	return result;
}


bool ScriptApiSecurity::checkPath(lua_State *L, const char *path,
		bool write_required, bool *write_allowed)
{
	if (write_allowed)
		*write_allowed = false;

	std::string str;  // Transient

	std::string abs_path = fs::AbsolutePath(path);

	if (!abs_path.empty()) {
		// Don't allow accessing the settings file
		str = fs::AbsolutePath(g_settings_path);
		if (str == abs_path) return false;
	}

	// If we couldn't find the absolute path (path doesn't exist) then
	// try removing the last components until it works (to allow
	// non-existent files/folders for mkdir).
	std::string cur_path = path;
	std::string removed;
	while (abs_path.empty() && !cur_path.empty()) {
		std::string component;
		cur_path = fs::RemoveLastPathComponent(cur_path, &component);
		if (component == "..") {
			// Parent components can't be allowed or we could allow something like
			// /home/user/minetest/worlds/foo/noexist/../../../../../../etc/passwd.
			// If we have previous non-relative elements in the path we might be
			// able to remove them so that things like worlds/foo/noexist/../auth.txt
			// could be allowed, but those paths will be interpreted as nonexistent
			// by the operating system anyways.
			return false;
		}
		removed.append(component).append(removed.empty() ? "" : DIR_DELIM + removed);
		abs_path = fs::AbsolutePath(cur_path);
	}
	if (abs_path.empty())
		return false;
	// Add the removed parts back so that you can't, eg, create a
	// directory in worldmods if worldmods doesn't exist.
	if (!removed.empty())
		abs_path += DIR_DELIM + removed;

	// Get server from registry
	lua_rawgeti(L, LUA_REGISTRYINDEX, CUSTOM_RIDX_SCRIPTAPI);
	ScriptApiBase *script = (ScriptApiBase *) lua_touserdata(L, -1);
	lua_pop(L, 1);
	const IGameDef *gamedef = script->getGameDef();
	if (!gamedef)
		return false;

	// Get mod name
	lua_rawgeti(L, LUA_REGISTRYINDEX, CUSTOM_RIDX_CURRENT_MOD_NAME);
	if (lua_isstring(L, -1)) {
		std::string mod_name = readParam<std::string>(L, -1);

		// Builtin can access anything
		if (mod_name == BUILTIN_MOD_NAME) {
			if (write_allowed) *write_allowed = true;
			return true;
		}

		// Allow paths in mod path
		// Don't bother if write access isn't important, since it will be handled later
		if (write_required || write_allowed != NULL) {
			const ModSpec *mod = gamedef->getModSpec(mod_name);
			if (mod) {
				str = fs::AbsolutePath(mod->path);
				if (!str.empty() && fs::PathStartsWith(abs_path, str)) {
					if (write_allowed) *write_allowed = true;
					return true;
				}
			}
		}
	}
	lua_pop(L, 1);  // Pop mod name

	// Allow read-only access to all mod directories
	if (!write_required) {
		const std::vector<ModSpec> &mods = gamedef->getMods();
		for (const ModSpec &mod : mods) {
			str = fs::AbsolutePath(mod.path);
			if (!str.empty() && fs::PathStartsWith(abs_path, str)) {
				return true;
			}
		}
	}

	str = fs::AbsolutePath(gamedef->getWorldPath());
	if (!str.empty()) {
		// Don't allow access to other paths in the world mod/game path.
		// These have to be blocked so you can't override a trusted mod
		// by creating a mod with the same name in a world mod directory.
		// We add to the absolute path of the world instead of getting
		// the absolute paths directly because that won't work if they
		// don't exist.
		if (fs::PathStartsWith(abs_path, str + DIR_DELIM + "worldmods") ||
				fs::PathStartsWith(abs_path, str + DIR_DELIM + "game")) {
			return false;
		}
		// Allow all other paths in world path
		if (fs::PathStartsWith(abs_path, str)) {
			if (write_allowed) *write_allowed = true;
			return true;
		}
	}

	// Default to disallowing
	return false;
}


int ScriptApiSecurity::sl_g_dofile(lua_State *L)
{
	int nret = sl_g_loadfile(L);
	if (nret != 1) {
		lua_error(L);
		// code after this function isn't executed
	}
	int top_precall = lua_gettop(L);
	lua_call(L, 0, LUA_MULTRET);
	// Return number of arguments returned by the function,
	// adjusting for the function being poped.
	return lua_gettop(L) - (top_precall - 1);
}


int ScriptApiSecurity::sl_g_load(lua_State *L)
{
	size_t len;
	const char *buf;
	std::string code;
	const char *chunk_name = "=(load)";

	luaL_checktype(L, 1, LUA_TFUNCTION);
	if (!lua_isnone(L, 2)) {
		luaL_checktype(L, 2, LUA_TSTRING);
		chunk_name = lua_tostring(L, 2);
	}

	while (true) {
		lua_pushvalue(L, 1);
		lua_call(L, 0, 1);
		int t = lua_type(L, -1);
		if (t == LUA_TNIL) {
			break;
		}

		if (t != LUA_TSTRING) {
			lua_pushnil(L);
			lua_pushliteral(L, "Loader didn't return a string");
			return 2;
		}
		buf = lua_tolstring(L, -1, &len);
		code += std::string(buf, len);
		lua_pop(L, 1); // Pop return value
	}
	if (!safeLoadString(L, code, chunk_name)) {
		lua_pushnil(L);
		lua_insert(L, -2);
		return 2;
	}
	return 1;
}


int ScriptApiSecurity::sl_g_loadfile(lua_State *L)
{
#ifndef SERVER
	lua_rawgeti(L, LUA_REGISTRYINDEX, CUSTOM_RIDX_SCRIPTAPI);
	ScriptApiBase *script = (ScriptApiBase *) lua_touserdata(L, -1);
	lua_pop(L, 1);

	// Client implementation
	if (script->getType() == ScriptingType::Client) {
		std::string path = readParam<std::string>(L, 1);
		const std::string *contents = script->getClient()->getModFile(path);
		if (!contents) {
			std::string error_msg = "Coudln't find script called: " + path;
			lua_pushnil(L);
			lua_pushstring(L, error_msg.c_str());
			return 2;
		}

		std::string chunk_name = "@" + path;
		if (!safeLoadString(L, *contents, chunk_name.c_str())) {
			lua_pushnil(L);
			lua_insert(L, -2);
			return 2;
		}
		return 1;
	}
#endif

	// Server implementation
	const char *path = NULL;
	if (lua_isstring(L, 1)) {
		path = lua_tostring(L, 1);
		CHECK_SECURE_PATH_INTERNAL(L, path, false, NULL);
	}

	if (!safeLoadFile(L, path)) {
		lua_pushnil(L);
		lua_insert(L, -2);
		return 2;
	}

	return 1;
}


int ScriptApiSecurity::sl_g_loadstring(lua_State *L)
{
	const char *chunk_name = "=(load)";

	luaL_checktype(L, 1, LUA_TSTRING);
	if (!lua_isnone(L, 2)) {
		luaL_checktype(L, 2, LUA_TSTRING);
		chunk_name = lua_tostring(L, 2);
	}

	size_t size;
	const char *code = lua_tolstring(L, 1, &size);
	std::string code_s(code, size);

	if (!safeLoadString(L, code_s, chunk_name)) {
		lua_pushnil(L);
		lua_insert(L, -2);
		return 2;
	}
	return 1;
}


int ScriptApiSecurity::sl_g_require(lua_State *L)
{
	lua_pushliteral(L, "require() is disabled when mod security is on.");
	return lua_error(L);
}


int ScriptApiSecurity::sl_io_open(lua_State *L)
{
	bool with_mode = lua_gettop(L) > 1;

	luaL_checktype(L, 1, LUA_TSTRING);
	const char *path = lua_tostring(L, 1);

	bool write_requested = false;
	if (with_mode) {
		luaL_checktype(L, 2, LUA_TSTRING);
		const char *mode = lua_tostring(L, 2);
		write_requested = strchr(mode, 'w') != NULL ||
			strchr(mode, '+') != NULL ||
			strchr(mode, 'a') != NULL;
	}
	CHECK_SECURE_PATH_INTERNAL(L, path, write_requested, NULL);

	push_original(L, "io", "open");
	lua_pushvalue(L, 1);
	if (with_mode) {
		lua_pushvalue(L, 2);
	}

	lua_call(L, with_mode ? 2 : 1, 2);
	return 2;
}


int ScriptApiSecurity::sl_io_input(lua_State *L)
{
	if (lua_isstring(L, 1)) {
		const char *path = lua_tostring(L, 1);
		CHECK_SECURE_PATH_INTERNAL(L, path, false, NULL);
	}

	push_original(L, "io", "input");
	lua_pushvalue(L, 1);
	lua_call(L, 1, 1);
	return 1;
}


int ScriptApiSecurity::sl_io_output(lua_State *L)
{
	if (lua_isstring(L, 1)) {
		const char *path = lua_tostring(L, 1);
		CHECK_SECURE_PATH_INTERNAL(L, path, true, NULL);
	}

	push_original(L, "io", "output");
	lua_pushvalue(L, 1);
	lua_call(L, 1, 1);
	return 1;
}


int ScriptApiSecurity::sl_io_lines(lua_State *L)
{
	if (lua_isstring(L, 1)) {
		const char *path = lua_tostring(L, 1);
		CHECK_SECURE_PATH_INTERNAL(L, path, false, NULL);
	}

	int top_precall = lua_gettop(L);
	push_original(L, "io", "lines");
	lua_pushvalue(L, 1);
	lua_call(L, 1, LUA_MULTRET);
	// Return number of arguments returned by the function,
	// adjusting for the function being poped.
	return lua_gettop(L) - top_precall;
}


int ScriptApiSecurity::sl_os_rename(lua_State *L)
{
	luaL_checktype(L, 1, LUA_TSTRING);
	const char *path1 = lua_tostring(L, 1);
	CHECK_SECURE_PATH_INTERNAL(L, path1, true, NULL);

	luaL_checktype(L, 2, LUA_TSTRING);
	const char *path2 = lua_tostring(L, 2);
	CHECK_SECURE_PATH_INTERNAL(L, path2, true, NULL);

	push_original(L, "os", "rename");
	lua_pushvalue(L, 1);
	lua_pushvalue(L, 2);
	lua_call(L, 2, 2);
	return 2;
}


int ScriptApiSecurity::sl_os_remove(lua_State *L)
{
	luaL_checktype(L, 1, LUA_TSTRING);
	const char *path = lua_tostring(L, 1);
	CHECK_SECURE_PATH_INTERNAL(L, path, true, NULL);

	push_original(L, "os", "remove");
	lua_pushvalue(L, 1);
	lua_call(L, 1, 2);
	return 2;
}
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 2016-05-22
*	DB::loadBlock copy removal & DB backend cleanup	Loic Blot	2016-05-17
*	Remove expensive copy of ContentFeatures	gregorycu	2016-03-30
*	Liquid flow: Prevent water spreading on ignore	paramat	2016-01-20
*	Liquids: Flow into and destroy 'floodable' nodes	paramat	2016-01-07
*	Rename macros with two leading underscores	ShadowNinja	2015-10-14
*	Use warningstream for log messages with WARNING	ShadowNinja	2015-10-14
*	Add emerge completion callback mechanism	kwolekr	2015-10-04
*	Define and use limit constants for Irrlicht fixed-width types	kwolekr	2015-10-04
*	Add /emergeblocks command and core.emerge_area() Lua API	kwolekr	2015-09-23
*	Fix segfault caused by a8e238ed06ee8285ed4459e9deda3117419837f6	Perttu Ahola	2015-08-13
*	Add count based unload limit for mapblocks	est31	2015-08-13
*	Add map limit config option	rubenwardy	2015-08-02
*	Record MapBlock modification reasons as flags instead of strings	kwolekr	2015-05-17
*	Ensure that Map::findNodesWithMetadata() reports nodes strictly within the no...	kwolekr	2015-05-08
*	Add core.find_nodes_with_meta() script API	kwolekr	2015-05-05
*	Move globals from main.cpp to more sane locations	Craig Robbins	2015-04-01
*	Respect game mapgen flags and save world noise params	ngosang	2015-03-07
*	For usages of assert() that are meant to persist in Release builds (when NDEB...	Craig Robbins	2015-03-07
*	Don't start a server for map migration	ShadowNinja	2015-03-06
*	Clean up database API and save the local map on an interval	ShadowNinja	2015-03-06
*	ABMHandler and player_collisions use sequential read/write. Switch from std::...	Loic Blot	2015-03-04
*	Fix unused (and so, broken) enable_rollback_recording. This option must be re...	Loic Blot	2015-02-18
*	Replace std::list by std::vector into ClientMap::updateDrawList, Map::timerUp...	Loic Blot	2015-02-17
*	Replace std::list by std::vector into timerUpdate calls	Loic Blot	2015-02-17
*	Replace std::list by std::vector into ServerMap::listAllLoadableBlocks Server...	Loic Blot	2015-02-17
*	Fix missing map_meta.txt error when creating new worlds	kwolekr	2015-01-27
*	Fix all warnings and remove -Wno-unused-but-set cflag	kwolekr	2015-01-18
*	Water fixes	gregorycu	2015-01-18
*	Create empty default constructor for MapNode	Craig Robbins	2015-01-18
*	Add ability to delete MapBlocks from map	kwolekr	2015-01-15
*	Change UniqueQueue to use a queue and a set.	unknown	2015-01-15
*	Fix use of uninitialized data	Craig Robbins	2015-01-14