ali@352: /*
ali@352:  * Copyright (C) 2009  J. Ali Harlow <ali@juiblex.co.uk>
ali@352:  *
ali@352:  * This program is free software; you can redistribute it and/or modify
ali@352:  * it under the terms of the GNU General Public License as published by
ali@352:  * the Free Software Foundation; either version 2 of the License, or
ali@352:  * (at your option) any later version.
ali@352:  *
ali@352:  * This program is distributed in the hope that it will be useful,
ali@352:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
ali@352:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
ali@352:  * GNU General Public License for more details.
ali@352:  *
ali@352:  * You should have received a copy of the GNU General Public License along
ali@352:  * with this program; if not, write to the Free Software Foundation, Inc.,
ali@352:  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
ali@352:  */
ali@352: 
ali@352: #include "config.h"
ali@352: 
ali@352: #include <stdlib.h>
ali@352: #include <string.h>
ali@352: #include <stdio.h>
ali@352: #include <errno.h>
ali@352: #include <sys/stat.h>
ali@352: #include <sys/types.h>
ali@352: #include <lua.h>
ali@352: #include <lualib.h>
ali@352: #include <lauxlib.h>
ali@352: 
ali@352: #include "razor.h"
ali@352: #include "razor-internal.h"
ali@352: 
ali@352: #define MAX_ARGS		2
ali@352: 
ali@352: #define ARG_FLAG_OPT		0x1
ali@352: #define ARG_FLAG_BYPASS		0x2
ali@352: 
ali@352: #define ARG(flags, swtch, index, type) \
ali@352: 				((flags) << 26 | (swtch) << 21 | \
ali@352: 				 (index) << 16 | type)
ali@352: #define ARG_FLAGS(arg)		((unsigned)(arg) >> 26)
ali@352: #define ARG_SWTCH(arg)		((unsigned)(arg) >> 21 & 0x1F)
ali@352: #define ARG_INDEX(arg)		((unsigned)(arg) >> 16 & 0x1F)
ali@352: #define ARG_TYPE(arg)		((unsigned)(arg) & 0xFFFF)
ali@352: 
ali@352: #define ARG_NONE		0
ali@352: #define ARG_STRING(n)		ARG(0, 0, n, LUA_TSTRING)
ali@352: #define ARG_OPT_STRING(n)	ARG(ARG_FLAG_OPT, 0, n, LUA_TSTRING)
ali@352: #define ARG_BYP_STRING(n, s)	ARG(ARG_FLAG_BYPASS, s, n, LUA_TSTRING)
ali@352: 
ali@352: struct razor_proxy {
ali@352: 	char *table, *name;
ali@352: 	int result;
ali@352: 	unsigned args[MAX_ARGS];
ali@352: };
ali@352: 
ali@352: static struct razor_proxy proxy[] = {
ali@352: 	{ NULL, "dofile", LUA_TNONE, { ARG_STRING(1) } },
ali@352: 	{ NULL, "loadfile", LUA_TNONE, { ARG_OPT_STRING(1) } },
ali@352: 	{ "io", "input", LUA_TNONE, { ARG_OPT_STRING(1) } },
ali@352: 	{ "io", "output", LUA_TNONE, { ARG_OPT_STRING(1) } },
ali@352: 	{ "io", "lines", LUA_TNONE, { ARG_OPT_STRING(1) } },
ali@352: 	{ "io", "open", LUA_TNONE, { ARG_STRING(1) } },
ali@352: 	{ "io", "popen", LUA_TNONE, { ARG_STRING(1) } },
ali@352: 	/*
ali@352: 	 * Note: We do not proxy os.execute
ali@352: 	 * We can't do it properly (there is no way to distinguish filenames
ali@352: 	 * in arguments from any other strings) so it's better not to try.
ali@352: 	 * Scripts that attempt to be portable should use posix.exec[p]
ali@352: 	 */
ali@352: 	{ "os", "remove", LUA_TNONE, { ARG_STRING(1) } },
ali@352: 	{ "os", "rename", LUA_TNONE, { ARG_STRING(1), ARG_STRING(2) } },
ali@352: 	/*
ali@352: 	 * Note: We do not proxy os.tmpname
ali@352: 	 * It should never be used. scripts should use io.tmpfile instead
ali@352: 	 * if the rather limited functionality it provides suffices. The
ali@352: 	 * proper solution is to implement posix.mkstemp
ali@352: 	 */
ali@352: 	{ "posix", "access", LUA_TNONE, { ARG_STRING(1) } },
ali@352: 	{ "posix", "chdir", LUA_TNONE, { ARG_STRING(1) } },
ali@352: 	{ "posix", "chmod", LUA_TNONE, { ARG_STRING(1) } },
ali@352: 	{ "posix", "chown", LUA_TNONE, { ARG_STRING(1) } },
ali@352: 	{ "posix", "dir", LUA_TNONE, { ARG_OPT_STRING(1) } },
ali@352: 	{ "posix", "exec", LUA_TNONE, { ARG_STRING(1) } },
ali@352: 	{ "posix", "execp", LUA_TNONE, { ARG_STRING(1) } },
ali@352: 	{ "posix", "files", LUA_TNONE, { ARG_OPT_STRING(1) } },
ali@352: 	{ "posix", "getcwd", LUA_TSTRING, { ARG_NONE } },
ali@352: 	{ "posix", "glob", LUA_TTABLE, { ARG_STRING(1) } },
ali@352: 	{ "posix", "link", LUA_TNONE, { ARG_BYP_STRING(1, 3), ARG_STRING(2) } },
ali@352: 	{ "posix", "mkdir", LUA_TNONE, { ARG_STRING(1) } },
ali@352: 	{ "posix", "mkfifo", LUA_TNONE, { ARG_STRING(1) } },
ali@352: 	{ "posix", "pathconf", LUA_TNONE, { ARG_STRING(1) } },
ali@352: 	{ "posix", "readlink", LUA_TNONE, { ARG_STRING(1) } },
ali@352: 	{ "posix", "rmdir", LUA_TNONE, { ARG_STRING(1) } },
ali@352: 	{ "posix", "stat", LUA_TNONE, { ARG_STRING(1) } },
ali@352: 	{ "posix", "unlink", LUA_TNONE, { ARG_STRING(1) } },
ali@352: 	{ "posix", "utime", LUA_TNONE, { ARG_STRING(1) } },
ali@352: };
ali@352: 
ali@352: static lua_CFunction execp_handler;
ali@352: 
ali@352: struct razor_lua {
ali@352: 	const char *root;
ali@352: 	lua_CFunction handler[ARRAY_SIZE(proxy)];
ali@352: };
ali@352: 
ali@352: static void *alloc_lua(void *user_data, void *ptr, size_t osize, size_t nsize)
ali@352: {
ali@352: 	if (!nsize) {
ali@352: 		free(ptr);
ali@352: 		return NULL;
ali@352: 	} else
ali@352: 		return realloc(ptr, nsize);
ali@352: }
ali@352: 
ali@352: static int proxy_execp(lua_State *L)
ali@352: {
ali@352: 	int r, n, err, got_eacces = 0;
ali@352: 	char *file = strdup(luaL_checkstring(L, 1));
ali@352: 	char *exe;
ali@352: 	const char *s, *e, *path;
ali@352: 	struct razor_lua *rl;
ali@352: 
ali@352: 	if (*file == '\0' || strchr(file, '/')) {
ali@352: 		r = execp_handler(L);
ali@352: 		free(file);
ali@352: 		return r;
ali@352: 	}
ali@352: 
ali@352: 	(void)lua_getallocf(L, (void **)&rl);
ali@352: 
ali@352: 	path = getenv("PATH");
ali@352: 	if (!path)
ali@352: 		path = ":/bin:/usr/bin";
ali@352: 
ali@352: 	s = path;
ali@352: 	for (;;) {
ali@352: 		e = strchr(s, ':');
ali@352: 		if (!e)
ali@352: 			e = s + strlen(s);
ali@352: 		if (*s == '/') {
ali@352: 			n = strlen(rl->root);
ali@352: 			exe = malloc(n + (e - s) + 1 + strlen(file) + 1);
ali@352: 			memcpy(exe, rl->root, n);
ali@352: 			memcpy(exe + n, s, e - s);
ali@352: 			n += e - s;
ali@352: 			exe[n++] = '/';
ali@352: 			strcpy(exe + n, file);
ali@352: 		} else if (e != s) {
ali@352: 			exe = malloc((e - s) + 1 + strlen(file) + 1);
ali@352: 			memcpy(exe, s, e - s);
ali@352: 			n = e - s;
ali@352: 			exe[n++] = '/';
ali@352: 			strcpy(exe + n, file);
ali@352: 		} else {
ali@352: 			/* Ensure exe contains a slash to avoid PATH search */
ali@352: 			exe = malloc(2 + strlen(file) + 1);
ali@352: 			exe[0] = '.';
ali@352: 			exe[1] = '/';
ali@352: 			strcpy(exe + 2, file);
ali@352: 		}
ali@352: 		lua_pushstring(L, exe);
ali@352: 		lua_replace(L, 1);
ali@352: 		free(exe);
ali@352: 		n = lua_gettop(L);
ali@352: 		r = execp_handler(L);
ali@352: 
ali@352: 		err = lua_tointeger(L, -1);
ali@352: 		switch (err) {
ali@352: 		case EACCES:
ali@352: 			got_eacces = 1;
ali@352: 			/* Fall through */
ali@352: 		case ENOENT:
ali@352: 		case ESTALE:
ali@352: 		case ENOTDIR:
ali@352: 		case ENODEV:
ali@352: 		case ETIMEDOUT:
ali@352: 			lua_pop(L, lua_gettop(L) - n);
ali@352: 			break;
ali@352: 		default:
ali@352: 			free(file);
ali@352: 			return r;
ali@352: 		}
ali@352: 
ali@352: 		if (*e)
ali@352: 			s = e + 1;
ali@352: 		else
ali@352: 			break;
ali@352: 	}
ali@352: 
ali@352: 	if (got_eacces)
ali@352: 		err = EACCES;
ali@352: 
ali@352: 	lua_pushnil(L);
ali@352: 	lua_pushfstring(L, "%s: %s", file, strerror(err));
ali@352: 	lua_pushinteger(L, err);
ali@352: 
ali@352: 	free(file);
ali@352: 	return 3;
ali@352: }
ali@352: 
ali@352: static int real2fake(lua_State *L, struct razor_lua *rl, int indx)
ali@352: {
ali@352: 	const char *path;
ali@352: 
ali@352: 	if (indx < 0)
ali@352: 		indx += lua_gettop(L) + 1;
ali@352: 
ali@352: 	if (lua_type(L, indx) == LUA_TSTRING) {
ali@352: 		path = lua_tostring(L, indx);
ali@352: 		if (path && !strncmp(path, rl->root, strlen(rl->root)) &&
ali@352: 		   (path[strlen(rl->root)] == '/' || !path[strlen(rl->root)])) {
ali@352: 			lua_pushstring(L, path + strlen(rl->root));
ali@352: 			lua_replace(L, indx);
ali@352: 			return 1;
ali@352: 		}
ali@352: 	}
ali@352: 
ali@352: 	return 0;
ali@352: }
ali@352: 
ali@352: static int proxy_handler(lua_State *L)
ali@352: {
ali@352: 	int i, retval, cond;
ali@352: 	unsigned arg;
ali@352: 	const char *path;
ali@352: 	struct razor_lua *rl;
ali@352: 	int method = lua_tointeger(L, lua_upvalueindex(1));
ali@352: 	struct razor_proxy *rp = proxy + method;
ali@352: 
ali@352: 	(void)lua_getallocf(L, (void **)&rl);
ali@352: 
ali@352: 	for(i = 0; i < MAX_ARGS; i++) {
ali@352: 		arg = rp->args[i];
ali@352: 		if (arg == ARG_NONE)
ali@352: 			continue;
ali@352: 		switch (ARG_TYPE(arg)) {
ali@352: 		case LUA_TSTRING:
ali@352: 			if (ARG_FLAGS(arg) & ARG_FLAG_BYPASS)
ali@352: 				cond = !lua_toboolean(L, ARG_SWTCH(arg));
ali@352: 			else
ali@352: 				cond = 1;
ali@352: 			if (ARG_FLAGS(arg) & ARG_FLAG_OPT) {
ali@352: 				if (lua_isstring(L, ARG_INDEX(arg)))
ali@352: 					path = lua_tostring(L, ARG_INDEX(arg));
ali@352: 				else
ali@352: 					path = NULL;
ali@352: 			} else
ali@352: 				path = luaL_checkstring(L, ARG_INDEX(arg));
ali@352: 			if (cond && path && *path == '/') {
ali@352: 				lua_pushfstring(L, "%s%s", rl->root, path);
ali@352: 				lua_replace(L, ARG_INDEX(arg));
ali@352: 			}
ali@352: 			break;
ali@352: 		default:
ali@352: 			lua_pushfstring(L, "razor proxy: Unhandled type (%d)",
ali@352: 					ARG_TYPE(arg));
ali@352: 			lua_error(L);
ali@352: 		}
ali@352: 	}
ali@352: 
ali@352: 	retval = rl->handler[method](L);
ali@352: 
ali@352: 	if (rp->result != LUA_TNONE && !lua_isnil(L, 1)) {
ali@352: 		switch (rp->result) {
ali@352: 		case LUA_TNONE:
ali@352: 			break;
ali@352: 		case LUA_TSTRING:
ali@352: 			real2fake(L, rl, -1);
ali@352: 			break;
ali@352: 		case LUA_TTABLE:
ali@352: 			lua_pushnil(L);
ali@352: 			while (lua_next(L, -2)) {
ali@352: 				if (real2fake(L, rl, -1)) {
ali@352: 					i = lua_tonumber(L, -2);
ali@352: 					lua_rawseti(L, -3, i);
ali@352: 				} else
ali@352: 					lua_pop(L, 1);
ali@352: 			}
ali@352: 			break;
ali@352: 		default:
ali@352: 			lua_pushfstring(L, "razor proxy: Unhandled type (%d)",
ali@352: 					rp->result);
ali@352: 			lua_error(L);
ali@352: 		}
ali@352: 	}
ali@352: 
ali@352: 	return retval;
ali@352: }
ali@352: 
ali@361: struct razor_lua_loader {
ali@361: 	uint32_t name;
ali@361: 	lua_CFunction func;
ali@361: };
ali@361: 
ali@361: static struct razor_preload {
ali@361: 	int init;
ali@361: 	struct hashtable modules;
ali@361: 	struct array name_pool;
ali@361: 	struct array loaders;
ali@361: } razor_preload = {0};
ali@361: 
ali@361: RAZOR_EXPORT void razor_set_lua_loader(const char *modname, void (*loader)())
ali@361: {
ali@361: 	uint32_t name;
ali@361: 	struct razor_lua_loader *ploader, *end;
ali@361: 
ali@361: 	if (!razor_preload.init) {
ali@361: 		razor_preload.init = 1;
ali@361: 		array_init(&razor_preload.name_pool);
ali@361: 		array_init(&razor_preload.loaders);
ali@361: 		hashtable_init(&razor_preload.modules,
ali@361: 			       &razor_preload.name_pool);
ali@361: 	}
ali@361: 
ali@361: 	name = hashtable_tokenize(&razor_preload.modules, modname);
ali@361: 
ali@361: 	end = razor_preload.loaders.data + razor_preload.loaders.size;
ali@361: 	for(ploader = razor_preload.loaders.data; ploader < end; ploader++)
ali@361: 		if (ploader->name == name) {
ali@361: 			ploader->func = loader;
ali@361: 			return;
ali@361: 		}
ali@361: 
ali@361: 	ploader = array_add(&razor_preload.loaders, sizeof(*ploader));
ali@361: 	ploader->name = name;
ali@361: 	ploader->func = loader;
ali@361: }
ali@361: 
ali@368: RAZOR_EXPORT void (*razor_get_lua_loader(const char *modname))()
ali@368: {
ali@368: 	uint32_t name;
ali@368: 	struct razor_lua_loader *ploader, *end;
ali@368: 
ali@368: 	if (!razor_preload.init)
ali@368: 		return 0;
ali@368: 
ali@368: 	name = hashtable_lookup(&razor_preload.modules, modname);
ali@368: 
ali@368: 	end = razor_preload.loaders.data + razor_preload.loaders.size;
ali@368: 	for(ploader = razor_preload.loaders.data; ploader < end; ploader++)
ali@368: 		if (ploader->name == name)
ali@368: 			return ploader->func;
ali@368: 
ali@368: 	return 0;
ali@368: }
ali@368: 
ali@361: static void razor_lua_preload(lua_State *L)
ali@361: {
ali@361: 	struct razor_lua_loader *ploader, *end;
ali@361: 
ali@361: 	if (!razor_preload.init)
ali@361: 		return;
ali@361: 
ali@361: 	lua_getfield(L, LUA_GLOBALSINDEX, "package");
ali@361: 	lua_getfield(L, -1, "preload");
ali@361: 	lua_remove(L, -2);
ali@361: 
ali@361: 	end = razor_preload.loaders.data + razor_preload.loaders.size;
ali@361: 	for(ploader = razor_preload.loaders.data; ploader < end; ploader++) {
ali@361: 		lua_pushcfunction(L, ploader->func);
ali@361: 		lua_setfield(L, -2,
ali@361: 			     razor_preload.name_pool.data + ploader->name);
ali@361: 	}
ali@361: 
ali@361: 	lua_pop(L, 1);
ali@361: }
ali@361: 
ali@352: int run_lua_script(const char *root, const char *name, const char *body,
ali@376: 		   ssize_t len, int arg1)
ali@352: {
ali@352: 	int i, n;
ali@352: 	lua_State *L;
ali@352: 	struct razor_lua rl;
ali@352: 
ali@352: 	if (root && strcmp(root, "/"))
ali@352: 		rl.root = root;
ali@352: 	else
ali@352: 		rl.root = NULL;
ali@352: 
ali@352: 	L = lua_newstate(alloc_lua, &rl);
ali@352: 	luaL_openlibs(L);
ali@361: 	razor_lua_preload(L);
ali@352: 	lua_getglobal(L, "require");
ali@352: 	lua_pushstring(L, "posix");
ali@352: 	if (lua_pcall(L, 1, 1, 0)) {
ali@352: 		fprintf(stderr, "lua posix: %s\n", lua_tostring(L, -1));
ali@352: 		lua_pop(L, 1);
ali@352: 		lua_close(L);
ali@352: 		return -1;
ali@352: 	}
ali@352: 
ali@352: 	if (rl.root)
ali@352: 		for(i = 0; i < ARRAY_SIZE(proxy); i++) {
ali@352: 			if (proxy[i].table) {
ali@352: 				lua_getglobal(L, proxy[i].table);
ali@352: 				n = lua_gettop(L);
ali@352: 			} else
ali@352: 				n = LUA_GLOBALSINDEX;
ali@352: 			lua_getfield(L, n, proxy[i].name);
ali@352: 			rl.handler[i] = lua_tocfunction(L, -1);
ali@352: 			lua_getfenv(L, -1);
ali@352: 			lua_remove(L, -2);
ali@352: 			if (proxy[i].table &&
ali@352: 			    !strcmp(proxy[i].table, "posix") &&
ali@352: 			    !strcmp(proxy[i].name, "execp")) {
ali@352: 				execp_handler = rl.handler[i];
ali@352: 				rl.handler[i] = proxy_execp;
ali@352: 			}
ali@352: 			lua_pushinteger(L, i);
ali@352: 			lua_pushcclosure(L, proxy_handler, 1);
ali@352: 			lua_pushvalue(L, -2);
ali@352: 			lua_setfenv(L, -2);
ali@352: 			lua_setfield(L, n, proxy[i].name);
ali@352: 			if (proxy[i].table)
ali@352: 				lua_pop(L, 2);
ali@352: 			else
ali@352: 				lua_pop(L, 1);
ali@352: 		}
ali@352: 
ali@352: 	if (len < 0)
ali@352: 		len = strlen(body);
ali@352: 
ali@352: 	if (luaL_loadbuffer(L, body, len, name)) {
ali@352: 		fprintf(stderr, "failed to load lua script\n");
ali@352: 		lua_close(L);
ali@352: 		return -1;
ali@352: 	}
ali@352: 
ali@376: 	lua_newtable(L);
ali@376: 	lua_pushvalue(L, LUA_GLOBALSINDEX);
ali@376: 	lua_pushliteral(L, "arg");
ali@376: 	lua_pushvalue(L, -3);
ali@376: 	lua_rawset(L, -3);
ali@376: 	lua_pop(L, 1);
ali@376: 	lua_pushliteral(L, "<lua>");
ali@376: 	lua_rawseti(L, -2, 1);
ali@376: 	if (arg1 >= 0) {
ali@376: 		lua_pushinteger(L, arg1);
ali@376: 		lua_rawseti(L, -2, 2);
ali@376: 	}
ali@376: 	lua_pop(L, 1);
ali@376: 
ali@352: 	if (lua_pcall(L, 0, 0, 0)) {
ali@352: 		fprintf(stderr, "lua script failed: %s\n", lua_tostring(L, -1));
ali@352: 		lua_pop(L, 1);
ali@352: 		lua_close(L);
ali@352: 		return -1;
ali@352: 	}
ali@352: 
ali@352: 	lua_close(L);
ali@352: 	return 0;
ali@352: }