path: root/src/keycode.cpp

/*
Minetest
Copyright (C) 2010-2013 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 "keycode.h"
#include "main.h" // For g_settings
#include "exceptions.h"
#include "settings.h"
#include "log.h"
#include "hex.h"

class UnknownKeycode : public BaseException
{
public:
	UnknownKeycode(const char *s) :
		BaseException(s) {};
};

#define CHECKKEY(x){if(strcmp(name, #x)==0) return irr::x;}

irr::EKEY_CODE keyname_to_keycode(const char *name)
{
	CHECKKEY(KEY_LBUTTON)
	CHECKKEY(KEY_RBUTTON)
	CHECKKEY(KEY_CANCEL)
	CHECKKEY(KEY_MBUTTON)
	CHECKKEY(KEY_XBUTTON1)
	CHECKKEY(KEY_XBUTTON2)
	CHECKKEY(KEY_BACK)
	CHECKKEY(KEY_TAB)
	CHECKKEY(KEY_CLEAR)
	CHECKKEY(KEY_RETURN)
	CHECKKEY(KEY_SHIFT)
	CHECKKEY(KEY_CONTROL)
	CHECKKEY(KEY_MENU)
	CHECKKEY(KEY_PAUSE)
	CHECKKEY(KEY_CAPITAL)
	CHECKKEY(KEY_KANA)
	CHECKKEY(KEY_HANGUEL)
	CHECKKEY(KEY_HANGUL)
	CHECKKEY(KEY_JUNJA)
	CHECKKEY(KEY_FINAL)
	CHECKKEY(KEY_HANJA)
	CHECKKEY(KEY_KANJI)
	CHECKKEY(KEY_ESCAPE)
	CHECKKEY(KEY_CONVERT)
	CHECKKEY(KEY_NONCONVERT)
	CHECKKEY(KEY_ACCEPT)
	CHECKKEY(KEY_MODECHANGE)
	CHECKKEY(KEY_SPACE)
	CHECKKEY(KEY_PRIOR)
	CHECKKEY(KEY_NEXT)
	CHECKKEY(KEY_END)
	CHECKKEY(KEY_HOME)
	CHECKKEY(KEY_LEFT)
	CHECKKEY(KEY_UP)
	CHECKKEY(KEY_RIGHT)
	CHECKKEY(KEY_DOWN)
	CHECKKEY(KEY_SELECT)
	CHECKKEY(KEY_PRINT)
	CHECKKEY(KEY_EXECUT)
	CHECKKEY(KEY_SNAPSHOT)
	CHECKKEY(KEY_INSERT)
	CHECKKEY(KEY_DELETE)
	CHECKKEY(KEY_HELP)
	CHECKKEY(KEY_KEY_0)
	CHECKKEY(KEY_KEY_1)
	CHECKKEY(KEY_KEY_2)
	CHECKKEY(KEY_KEY_3)
	CHECKKEY(KEY_KEY_4)
	CHECKKEY(KEY_KEY_5)
	CHECKKEY(KEY_KEY_6)
	CHECKKEY(KEY_KEY_7)
	CHECKKEY(KEY_KEY_8)
	CHECKKEY(KEY_KEY_9)
	CHECKKEY(KEY_KEY_A)
	CHECKKEY(KEY_KEY_B)
	CHECKKEY(KEY_KEY_C)
	CHECKKEY(KEY_KEY_D)
	CHECKKEY(KEY_KEY_E)
	CHECKKEY(KEY_KEY_F)
	CHECKKEY(KEY_KEY_G)
	CHECKKEY(KEY_KEY_H)
	CHECKKEY(KEY_KEY_I)
	CHECKKEY(KEY_KEY_J)
	CHECKKEY(KEY_KEY_K)
	CHECKKEY(KEY_KEY_L)
	CHECKKEY(KEY_KEY_M)
	CHECKKEY(KEY_KEY_N)
	CHECKKEY(KEY_KEY_O)
	CHECKKEY(KEY_KEY_P)
	CHECKKEY(KEY_KEY_Q)
	CHECKKEY(KEY_KEY_R)
	CHECKKEY(KEY_KEY_S)
	CHECKKEY(KEY_KEY_T)
	CHECKKEY(KEY_KEY_U)
	CHECKKEY(KEY_KEY_V)
	CHECKKEY(KEY_KEY_W)
	CHECKKEY(KEY_KEY_X)
	CHECKKEY(KEY_KEY_Y)
	CHECKKEY(KEY_KEY_Z)
	CHECKKEY(KEY_LWIN)
	CHECKKEY(KEY_RWIN)
	CHECKKEY(KEY_APPS)
	CHECKKEY(KEY_SLEEP)
	CHECKKEY(KEY_NUMPAD0)
	CHECKKEY(KEY_NUMPAD1)
	CHECKKEY(KEY_NUMPAD2)
	CHECKKEY(KEY_NUMPAD3)
	CHECKKEY(KEY_NUMPAD4)
	CHECKKEY(KEY_NUMPAD5)
	CHECKKEY(KEY_NUMPAD6)
	CHECKKEY(KEY_NUMPAD7)
	CHECKKEY(KEY_NUMPAD8)
	CHECKKEY(KEY_NUMPAD9)
	CHECKKEY(KEY_MULTIPLY)
	CHECKKEY(KEY_ADD)
	CHECKKEY(KEY_SEPARATOR)
	CHECKKEY(KEY_SUBTRACT)
	CHECKKEY(KEY_DECIMAL)
	CHECKKEY(KEY_DIVIDE)
	CHECKKEY(KEY_F1)
	CHECKKEY(KEY_F2)
	CHECKKEY(KEY_F3)
	CHECKKEY(KEY_F4)
	CHECKKEY(KEY_F5)
	CHECKKEY(KEY_F6)
	CHECKKEY(KEY_F7)
	CHECKKEY(KEY_F8)
	CHECKKEY(KEY_F9)
	CHECKKEY(KEY_F10)
	CHECKKEY(KEY_F11)
	CHECKKEY(KEY_F12)
	CHECKKEY(KEY_F13)
	CHECKKEY(KEY_F14)
	CHECKKEY(KEY_F15)
	CHECKKEY(KEY_F16)
	CHECKKEY(KEY_F17)
	CHECKKEY(KEY_F18)
	CHECKKEY(KEY_F19)
	CHECKKEY(KEY_F20)
	CHECKKEY(KEY_F21)
	CHECKKEY(KEY_F22)
	CHECKKEY(KEY_F23)
	CHECKKEY(KEY_F24)
	CHECKKEY(KEY_NUMLOCK)
	CHECKKEY(KEY_SCROLL)
	CHECKKEY(KEY_LSHIFT)
	CHECKKEY(KEY_RSHIFT)
	CHECKKEY(KEY_LCONTROL)
	CHECKKEY(KEY_RCONTROL)
	CHECKKEY(KEY_LMENU)
	CHECKKEY(KEY_RMENU)
	CHECKKEY(KEY_PLUS)
	CHECKKEY(KEY_COMMA)
	CHECKKEY(KEY_MINUS)
	CHECKKEY(KEY_PERIOD)
	CHECKKEY(KEY_ATTN)
	CHECKKEY(KEY_CRSEL)
	CHECKKEY(KEY_EXSEL)
	CHECKKEY(KEY_EREOF)
	CHECKKEY(KEY_PLAY)
	CHECKKEY(KEY_ZOOM)
	CHECKKEY(KEY_PA1)
	CHECKKEY(KEY_OEM_CLEAR)

	throw UnknownKeycode(name);
}

static const char *KeyNames[] =
{ "-", "KEY_LBUTTON", "KEY_RBUTTON", "KEY_CANCEL", "KEY_MBUTTON", "KEY_XBUTTON1",
		"KEY_XBUTTON2", "-", "KEY_BACK", "KEY_TAB", "-", "-", "KEY_CLEAR", "KEY_RETURN", "-",
		"-", "KEY_SHIFT", "KEY_CONTROL", "KEY_MENU", "KEY_PAUSE", "KEY_CAPITAL", "KEY_KANA", "-",
		"KEY_JUNJA", "KEY_FINAL", "KEY_KANJI", "-", "KEY_ESCAPE", "KEY_CONVERT", "KEY_NONCONVERT",
		"KEY_ACCEPT", "KEY_MODECHANGE", "KEY_SPACE", "KEY_PRIOR", "KEY_NEXT", "KEY_END",
		"KEY_HOME", "KEY_LEFT", "KEY_UP", "KEY_RIGHT", "KEY_DOWN", "KEY_SELECT", "KEY_PRINT",
		"KEY_EXECUTE", "KEY_SNAPSHOT", "KEY_INSERT", "KEY_DELETE", "KEY_HELP", "KEY_KEY_0",
		"KEY_KEY_1", "KEY_KEY_2", "KEY_KEY_3", "KEY_KEY_4", "KEY_KEY_5",
		"KEY_KEY_6", "KEY_KEY_7", "KEY_KEY_8", "KEY_KEY_9", "-", "-", "-", "-",
		"-", "-", "-", "KEY_KEY_A", "KEY_KEY_B", "KEY_KEY_C", "KEY_KEY_D",
		"KEY_KEY_E", "KEY_KEY_F", "KEY_KEY_G", "KEY_KEY_H", "KEY_KEY_I",
		"KEY_KEY_J", "KEY_KEY_K", "KEY_KEY_L", "KEY_KEY_M", "KEY_KEY_N",
		"KEY_KEY_O", "KEY_KEY_P", "KEY_KEY_Q", "KEY_KEY_R", "KEY_KEY_S",
		"KEY_KEY_T", "KEY_KEY_U", "KEY_KEY_V", "KEY_KEY_W", "KEY_KEY_X",
		"KEY_KEY_Y", "KEY_KEY_Z", "KEY_LWIN", "KEY_RWIN", "KEY_APPS", "-",
		"KEY_SLEEP", "KEY_NUMPAD0", "KEY_NUMPAD1", "KEY_NUMPAD2", "KEY_NUMPAD3",
		"KEY_NUMPAD4", "KEY_NUMPAD5", "KEY_NUMPAD6", "KEY_NUMPAD7",
		"KEY_NUMPAD8", "KEY_NUMPAD9", "KEY_MULTIPLY", "KEY_ADD", "KEY_SEPERATOR",
		"KEY_SUBTRACT", "KEY_DECIMAL", "KEY_DIVIDE", "KEY_F1", "KEY_F2", "KEY_F3",
		"KEY_F4", "KEY_F5", "KEY_F6", "KEY_F7", "KEY_F8", "KEY_F9", "KEY_F10",
		"KEY_F11", "KEY_F12", "KEY_F13", "KEY_F14", "KEY_F15", "KEY_F16",
		"KEY_F17", "KEY_F18", "KEY_F19", "KEY_F20", "KEY_F21", "KEY_F22",
		"KEY_F23", "KEY_F24", "-", "-", "-", "-", "-", "-", "-", "-",
		"KEY_NUMLOCK", "KEY_SCROLL", "-", "-", "-", "-", "-", "-", "-", "-", "-",
		"-", "-", "-", "-", "-", "KEY_LSHIFT", "KEY_RSHIFT", "KEY_LCONTROL",
		"KEY_RCONTROL", "KEY_LMENU", "KEY_RMENU", "-", "-", "-", "-", "-",
		"-", "-", "-", "-", "-", "-", "-", "-", "-", "-", "-", "-", "-", "-",
		"-", "-", "KEY_PLUS", "KEY_COMMA", "KEY_MINUS", "KEY_PERIOD", "-", "-", "-", "-", "-",
		"-", "-", "-", "-", "-", "-", "-", "-", "-", "-", "-", "-", "-", "-",
		"-", "-", "-", "-", "-", "-", "-", "-", "-", "-", "-", "-", "-", "-",
		"-", "-", "-", "-", "-", "-", "-", "-", "-", "-", "-", "-", "-", "-",
		"-", "-", "-", "-", "-", "-", "-", "-", "KEY_ATTN", "KEY_CRSEL", "KEY_EXSEL",
		"KEY_EREOF", "KEY_PLAY", "KEY_ZOOM", "KEY_PA1", "KEY_OEM_CLEAR", "-" };

#define N_(text) text

static const char *KeyNamesLang[] =
	{ "-", N_("Left Button"), N_("Right Button"), N_("Cancel"), N_("Middle Button"), N_("X Button 1"),
			N_("X Button 2"), "-", N_("Back"), N_("Tab"), "-", "-", N_("Clear"), N_("Return"), "-",
			"-", N_("Shift"), N_("Control"), N_("Menu"), N_("Pause"), N_("Capital"), N_("Kana"), "-",
			N_("Junja"), N_("Final"), N_("Kanji"), "-", N_("Escape"), N_("Convert"), N_("Nonconvert"),
			N_("Accept"), N_("Mode Change"), N_("Space"), N_("Prior"), N_("Next"), N_("End"), N_("Home"),
			N_("Left"), N_("Up"), N_("Right"), N_("Down"), N_("Select"), N_("Print"), N_("Execute"),
			N_("Snapshot"), N_("Insert"), N_("Delete"), N_("Help"), "0", "1", "2", "3", "4", "5",
			"6", "7", "8", "9", "-", "-", "-", "-", "-", "-", "-", "A", "B", "C",
			"D", "E", "F", "G", "H", "I", "J", "K", "L", "M", "N", "O", "P", "Q",
			"R", "S", "T", "U", "V", "W", "X", "Y", "Z", N_("Left Windows"),
			N_("Right Windows"), N_("Apps"), "-", N_("Sleep"), N_("Numpad 0"), N_("Numpad 1"),
			N_("Numpad 2"), N_("Numpad 3"), N_("Numpad 4"), N_("Numpad 5"), N_("Numpad 6"), N_("Numpad 7"),
			N_("Numpad 8"), N_("Numpad 9"), N_("Numpad *"), N_("Numpad +"), N_("Numpad /"), N_("Numpad -"),
			"Numpad .", "Numpad /", "F1", "F2", "F3", "F4", "F5", "F6", "F7", "F8",
			,
		"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;
		}
		size_t len = strlen(display_name) + 2;
		chunk_name = new char[len];
		snprintf(chunk_name, len, "@%s", 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() ? "" :