diff options
Diffstat (limited to 'src/script_lua.c')
| -rw-r--r-- | src/script_lua.c | 1741 |
1 files changed, 1741 insertions, 0 deletions
diff --git a/src/script_lua.c b/src/script_lua.c new file mode 100644 index 0000000..33ed2aa --- /dev/null +++ b/src/script_lua.c @@ -0,0 +1,1741 @@ +/* + * Copyright (c) 2009-2021, Redis Ltd. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * + * * Redistributions of source code must retain the above copyright notice, + * this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * * Neither the name of Redis nor the names of its contributors may be used + * to endorse or promote products derived from this software without + * specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE + * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + */ + +#include "script_lua.h" + +#include "server.h" +#include "sha1.h" +#include "rand.h" +#include "cluster.h" +#include "monotonic.h" +#include "resp_parser.h" +#include "version.h" +#include <lauxlib.h> +#include <lualib.h> +#include <ctype.h> +#include <math.h> + +/* Globals that are added by the Lua libraries */ +static char *libraries_allow_list[] = { + "string", + "cjson", + "bit", + "cmsgpack", + "math", + "table", + "struct", + NULL, +}; + +/* Redis Lua API globals */ +static char *redis_api_allow_list[] = { + "redis", + "__redis__err__handler", /* error handler for eval, currently located on globals. + Should move to registry. */ + NULL, +}; + +/* Lua builtins */ +static char *lua_builtins_allow_list[] = { + "xpcall", + "tostring", + "getfenv", + "setmetatable", + "next", + "assert", + "tonumber", + "rawequal", + "collectgarbage", + "getmetatable", + "rawset", + "pcall", + "coroutine", + "type", + "_G", + "select", + "unpack", + "gcinfo", + "pairs", + "rawget", + "loadstring", + "ipairs", + "_VERSION", + "setfenv", + "load", + "error", + NULL, +}; + +/* Lua builtins which are not documented on the Lua documentation */ +static char *lua_builtins_not_documented_allow_list[] = { + "newproxy", + NULL, +}; + +/* Lua builtins which are allowed on initialization but will be removed right after */ +static char *lua_builtins_removed_after_initialization_allow_list[] = { + "debug", /* debug will be set to nil after the error handler will be created */ + NULL, +}; + +/* Those allow lists was created from the globals that was + * available to the user when the allow lists was first introduce. + * Because we do not want to break backward compatibility we keep + * all the globals. The allow lists will prevent us from accidentally + * creating unwanted globals in the future. + * + * Also notice that the allow list is only checked on start time, + * after that the global table is locked so not need to check anything.*/ +static char **allow_lists[] = { + libraries_allow_list, + redis_api_allow_list, + lua_builtins_allow_list, + lua_builtins_not_documented_allow_list, + lua_builtins_removed_after_initialization_allow_list, + NULL, +}; + +/* Deny list contains elements which we know we do not want to add to globals + * and there is no need to print a warning message form them. We will print a + * log message only if an element was added to the globals and the element is + * not on the allow list nor on the back list. */ +static char *deny_list[] = { + "dofile", + "loadfile", + "print", + NULL, +}; + +static int redis_math_random (lua_State *L); +static int redis_math_randomseed (lua_State *L); +static void redisProtocolToLuaType_Int(void *ctx, long long val, const char *proto, size_t proto_len); +static void redisProtocolToLuaType_BulkString(void *ctx, const char *str, size_t len, const char *proto, size_t proto_len); +static void redisProtocolToLuaType_NullBulkString(void *ctx, const char *proto, size_t proto_len); +static void redisProtocolToLuaType_NullArray(void *ctx, const char *proto, size_t proto_len); +static void redisProtocolToLuaType_Status(void *ctx, const char *str, size_t len, const char *proto, size_t proto_len); +static void redisProtocolToLuaType_Error(void *ctx, const char *str, size_t len, const char *proto, size_t proto_len); +static void redisProtocolToLuaType_Array(struct ReplyParser *parser, void *ctx, size_t len, const char *proto); +static void redisProtocolToLuaType_Map(struct ReplyParser *parser, void *ctx, size_t len, const char *proto); +static void redisProtocolToLuaType_Set(struct ReplyParser *parser, void *ctx, size_t len, const char *proto); +static void redisProtocolToLuaType_Null(void *ctx, const char *proto, size_t proto_len); +static void redisProtocolToLuaType_Bool(void *ctx, int val, const char *proto, size_t proto_len); +static void redisProtocolToLuaType_Double(void *ctx, double d, const char *proto, size_t proto_len); +static void redisProtocolToLuaType_BigNumber(void *ctx, const char *str, size_t len, const char *proto, size_t proto_len); +static void redisProtocolToLuaType_VerbatimString(void *ctx, const char *format, const char *str, size_t len, const char *proto, size_t proto_len); +static void redisProtocolToLuaType_Attribute(struct ReplyParser *parser, void *ctx, size_t len, const char *proto); +static void luaReplyToRedisReply(client *c, client* script_client, lua_State *lua); + +/* + * Save the give pointer on Lua registry, used to save the Lua context and + * function context so we can retrieve them from lua_State. + */ +void luaSaveOnRegistry(lua_State* lua, const char* name, void* ptr) { + lua_pushstring(lua, name); + if (ptr) { + lua_pushlightuserdata(lua, ptr); + } else { + lua_pushnil(lua); + } + lua_settable(lua, LUA_REGISTRYINDEX); +} + +/* + * Get a saved pointer from registry + */ +void* luaGetFromRegistry(lua_State* lua, const char* name) { + lua_pushstring(lua, name); + lua_gettable(lua, LUA_REGISTRYINDEX); + + if (lua_isnil(lua, -1)) { + return NULL; + } + /* must be light user data */ + serverAssert(lua_islightuserdata(lua, -1)); + + void* ptr = (void*) lua_topointer(lua, -1); + serverAssert(ptr); + + /* pops the value */ + lua_pop(lua, 1); + + return ptr; +} + +/* --------------------------------------------------------------------------- + * Redis reply to Lua type conversion functions. + * ------------------------------------------------------------------------- */ + +/* Take a Redis reply in the Redis protocol format and convert it into a + * Lua type. Thanks to this function, and the introduction of not connected + * clients, it is trivial to implement the redis() lua function. + * + * Basically we take the arguments, execute the Redis command in the context + * of a non connected client, then take the generated reply and convert it + * into a suitable Lua type. With this trick the scripting feature does not + * need the introduction of a full Redis internals API. The script + * is like a normal client that bypasses all the slow I/O paths. + * + * Note: in this function we do not do any sanity check as the reply is + * generated by Redis directly. This allows us to go faster. + * + * Errors are returned as a table with a single 'err' field set to the + * error string. + */ + +static const ReplyParserCallbacks DefaultLuaTypeParserCallbacks = { + .null_array_callback = redisProtocolToLuaType_NullArray, + .bulk_string_callback = redisProtocolToLuaType_BulkString, + .null_bulk_string_callback = redisProtocolToLuaType_NullBulkString, + .error_callback = redisProtocolToLuaType_Error, + .simple_str_callback = redisProtocolToLuaType_Status, + .long_callback = redisProtocolToLuaType_Int, + .array_callback = redisProtocolToLuaType_Array, + .set_callback = redisProtocolToLuaType_Set, + .map_callback = redisProtocolToLuaType_Map, + .bool_callback = redisProtocolToLuaType_Bool, + .double_callback = redisProtocolToLuaType_Double, + .null_callback = redisProtocolToLuaType_Null, + .big_number_callback = redisProtocolToLuaType_BigNumber, + .verbatim_string_callback = redisProtocolToLuaType_VerbatimString, + .attribute_callback = redisProtocolToLuaType_Attribute, + .error = NULL, +}; + +static void redisProtocolToLuaType(lua_State *lua, char* reply) { + ReplyParser parser = {.curr_location = reply, .callbacks = DefaultLuaTypeParserCallbacks}; + + parseReply(&parser, lua); +} + +static void redisProtocolToLuaType_Int(void *ctx, long long val, const char *proto, size_t proto_len) { + UNUSED(proto); + UNUSED(proto_len); + if (!ctx) { + return; + } + + lua_State *lua = ctx; + if (!lua_checkstack(lua, 1)) { + /* Increase the Lua stack if needed, to make sure there is enough room + * to push elements to the stack. On failure, exit with panic. */ + serverPanic("lua stack limit reach when parsing redis.call reply"); + } + lua_pushnumber(lua,(lua_Number)val); +} + +static void redisProtocolToLuaType_NullBulkString(void *ctx, const char *proto, size_t proto_len) { + UNUSED(proto); + UNUSED(proto_len); + if (!ctx) { + return; + } + + lua_State *lua = ctx; + if (!lua_checkstack(lua, 1)) { + /* Increase the Lua stack if needed, to make sure there is enough room + * to push elements to the stack. On failure, exit with panic. */ + serverPanic("lua stack limit reach when parsing redis.call reply"); + } + lua_pushboolean(lua,0); +} + +static void redisProtocolToLuaType_NullArray(void *ctx, const char *proto, size_t proto_len) { + UNUSED(proto); + UNUSED(proto_len); + if (!ctx) { + return; + } + lua_State *lua = ctx; + if (!lua_checkstack(lua, 1)) { + /* Increase the Lua stack if needed, to make sure there is enough room + * to push elements to the stack. On failure, exit with panic. */ + serverPanic("lua stack limit reach when parsing redis.call reply"); + } + lua_pushboolean(lua,0); +} + + +static void redisProtocolToLuaType_BulkString(void *ctx, const char *str, size_t len, const char *proto, size_t proto_len) { + UNUSED(proto); + UNUSED(proto_len); + if (!ctx) { + return; + } + + lua_State *lua = ctx; + if (!lua_checkstack(lua, 1)) { + /* Increase the Lua stack if needed, to make sure there is enough room + * to push elements to the stack. On failure, exit with panic. */ + serverPanic("lua stack limit reach when parsing redis.call reply"); + } + lua_pushlstring(lua,str,len); +} + +static void redisProtocolToLuaType_Status(void *ctx, const char *str, size_t len, const char *proto, size_t proto_len) { + UNUSED(proto); + UNUSED(proto_len); + if (!ctx) { + return; + } + + lua_State *lua = ctx; + if (!lua_checkstack(lua, 3)) { + /* Increase the Lua stack if needed, to make sure there is enough room + * to push elements to the stack. On failure, exit with panic. */ + serverPanic("lua stack limit reach when parsing redis.call reply"); + } + lua_newtable(lua); + lua_pushstring(lua,"ok"); + lua_pushlstring(lua,str,len); + lua_settable(lua,-3); +} + +static void redisProtocolToLuaType_Error(void *ctx, const char *str, size_t len, const char *proto, size_t proto_len) { + UNUSED(proto); + UNUSED(proto_len); + if (!ctx) { + return; + } + + lua_State *lua = ctx; + if (!lua_checkstack(lua, 3)) { + /* Increase the Lua stack if needed, to make sure there is enough room + * to push elements to the stack. On failure, exit with panic. */ + serverPanic("lua stack limit reach when parsing redis.call reply"); + } + sds err_msg = sdscatlen(sdsnew("-"), str, len); + luaPushErrorBuff(lua,err_msg); + /* push a field indicate to ignore updating the stats on this error + * because it was already updated when executing the command. */ + lua_pushstring(lua,"ignore_error_stats_update"); + lua_pushboolean(lua, 1); + lua_settable(lua,-3); +} + +static void redisProtocolToLuaType_Map(struct ReplyParser *parser, void *ctx, size_t len, const char *proto) { + UNUSED(proto); + lua_State *lua = ctx; + if (lua) { + if (!lua_checkstack(lua, 3)) { + /* Increase the Lua stack if needed, to make sure there is enough room + * to push elements to the stack. On failure, exit with panic. */ + serverPanic("lua stack limit reach when parsing redis.call reply"); + } + lua_newtable(lua); + lua_pushstring(lua, "map"); + lua_newtable(lua); + } + for (size_t j = 0; j < len; j++) { + parseReply(parser,lua); + parseReply(parser,lua); + if (lua) lua_settable(lua,-3); + } + if (lua) lua_settable(lua,-3); +} + +static void redisProtocolToLuaType_Set(struct ReplyParser *parser, void *ctx, size_t len, const char *proto) { + UNUSED(proto); + + lua_State *lua = ctx; + if (lua) { + if (!lua_checkstack(lua, 3)) { + /* Increase the Lua stack if needed, to make sure there is enough room + * to push elements to the stack. On failure, exit with panic. */ + serverPanic("lua stack limit reach when parsing redis.call reply"); + } + lua_newtable(lua); + lua_pushstring(lua, "set"); + lua_newtable(lua); + } + for (size_t j = 0; j < len; j++) { + parseReply(parser,lua); + if (lua) { + if (!lua_checkstack(lua, 1)) { + /* Increase the Lua stack if needed, to make sure there is enough room + * to push elements to the stack. On failure, exit with panic. + * Notice that here we need to check the stack again because the recursive + * call to redisProtocolToLuaType might have use the room allocated in the stack*/ + serverPanic("lua stack limit reach when parsing redis.call reply"); + } + lua_pushboolean(lua,1); + lua_settable(lua,-3); + } + } + if (lua) lua_settable(lua,-3); +} + +static void redisProtocolToLuaType_Array(struct ReplyParser *parser, void *ctx, size_t len, const char *proto) { + UNUSED(proto); + + lua_State *lua = ctx; + if (lua){ + if (!lua_checkstack(lua, 2)) { + /* Increase the Lua stack if needed, to make sure there is enough room + * to push elements to the stack. On failure, exit with panic. */ + serverPanic("lua stack limit reach when parsing redis.call reply"); + } + lua_newtable(lua); + } + for (size_t j = 0; j < len; j++) { + if (lua) lua_pushnumber(lua,j+1); + parseReply(parser,lua); + if (lua) lua_settable(lua,-3); + } +} + +static void redisProtocolToLuaType_Attribute(struct ReplyParser *parser, void *ctx, size_t len, const char *proto) { + UNUSED(proto); + + /* Parse the attribute reply. + * Currently, we do not expose the attribute to the Lua script so + * we just need to continue parsing and ignore it (the NULL ensures that the + * reply will be ignored). */ + for (size_t j = 0; j < len; j++) { + parseReply(parser,NULL); + parseReply(parser,NULL); + } + + /* Parse the reply itself. */ + parseReply(parser,ctx); +} + +static void redisProtocolToLuaType_VerbatimString(void *ctx, const char *format, const char *str, size_t len, const char *proto, size_t proto_len) { + UNUSED(proto); + UNUSED(proto_len); + if (!ctx) { + return; + } + + lua_State *lua = ctx; + if (!lua_checkstack(lua, 5)) { + /* Increase the Lua stack if needed, to make sure there is enough room + * to push elements to the stack. On failure, exit with panic. */ + serverPanic("lua stack limit reach when parsing redis.call reply"); + } + lua_newtable(lua); + lua_pushstring(lua,"verbatim_string"); + lua_newtable(lua); + lua_pushstring(lua,"string"); + lua_pushlstring(lua,str,len); + lua_settable(lua,-3); + lua_pushstring(lua,"format"); + lua_pushlstring(lua,format,3); + lua_settable(lua,-3); + lua_settable(lua,-3); +} + +static void redisProtocolToLuaType_BigNumber(void *ctx, const char *str, size_t len, const char *proto, size_t proto_len) { + UNUSED(proto); + UNUSED(proto_len); + if (!ctx) { + return; + } + + lua_State *lua = ctx; + if (!lua_checkstack(lua, 3)) { + /* Increase the Lua stack if needed, to make sure there is enough room + * to push elements to the stack. On failure, exit with panic. */ + serverPanic("lua stack limit reach when parsing redis.call reply"); + } + lua_newtable(lua); + lua_pushstring(lua,"big_number"); + lua_pushlstring(lua,str,len); + lua_settable(lua,-3); +} + +static void redisProtocolToLuaType_Null(void *ctx, const char *proto, size_t proto_len) { + UNUSED(proto); + UNUSED(proto_len); + if (!ctx) { + return; + } + + lua_State *lua = ctx; + if (!lua_checkstack(lua, 1)) { + /* Increase the Lua stack if needed, to make sure there is enough room + * to push elements to the stack. On failure, exit with panic. */ + serverPanic("lua stack limit reach when parsing redis.call reply"); + } + lua_pushnil(lua); +} + +static void redisProtocolToLuaType_Bool(void *ctx, int val, const char *proto, size_t proto_len) { + UNUSED(proto); + UNUSED(proto_len); + if (!ctx) { + return; + } + + lua_State *lua = ctx; + if (!lua_checkstack(lua, 1)) { + /* Increase the Lua stack if needed, to make sure there is enough room + * to push elements to the stack. On failure, exit with panic. */ + serverPanic("lua stack limit reach when parsing redis.call reply"); + } + lua_pushboolean(lua,val); +} + +static void redisProtocolToLuaType_Double(void *ctx, double d, const char *proto, size_t proto_len) { + UNUSED(proto); + UNUSED(proto_len); + if (!ctx) { + return; + } + + lua_State *lua = ctx; + if (!lua_checkstack(lua, 3)) { + /* Increase the Lua stack if needed, to make sure there is enough room + * to push elements to the stack. On failure, exit with panic. */ + serverPanic("lua stack limit reach when parsing redis.call reply"); + } + lua_newtable(lua); + lua_pushstring(lua,"double"); + lua_pushnumber(lua,d); + lua_settable(lua,-3); +} + +/* This function is used in order to push an error on the Lua stack in the + * format used by redis.pcall to return errors, which is a lua table + * with an "err" field set to the error string including the error code. + * Note that this table is never a valid reply by proper commands, + * since the returned tables are otherwise always indexed by integers, never by strings. + * + * The function takes ownership on the given err_buffer. */ +void luaPushErrorBuff(lua_State *lua, sds err_buffer) { + sds msg; + sds error_code; + + /* If debugging is active and in step mode, log errors resulting from + * Redis commands. */ + if (ldbIsEnabled()) { + ldbLog(sdscatprintf(sdsempty(),"<error> %s",err_buffer)); + } + + /* There are two possible formats for the received `error` string: + * 1) "-CODE msg": in this case we remove the leading '-' since we don't store it as part of the lua error format. + * 2) "msg": in this case we prepend a generic 'ERR' code since all error statuses need some error code. + * We support format (1) so this function can reuse the error messages used in other places in redis. + * We support format (2) so it'll be easy to pass descriptive errors to this function without worrying about format. + */ + if (err_buffer[0] == '-') { + /* derive error code from the message */ + char *err_msg = strstr(err_buffer, " "); + if (!err_msg) { + msg = sdsnew(err_buffer+1); + error_code = sdsnew("ERR"); + } else { + *err_msg = '\0'; + msg = sdsnew(err_msg+1); + error_code = sdsnew(err_buffer + 1); + } + sdsfree(err_buffer); + } else { + msg = err_buffer; + error_code = sdsnew("ERR"); + } + /* Trim newline at end of string. If we reuse the ready-made Redis error objects (case 1 above) then we might + * have a newline that needs to be trimmed. In any case the lua Redis error table shouldn't end with a newline. */ + msg = sdstrim(msg, "\r\n"); + sds final_msg = sdscatfmt(error_code, " %s", msg); + + lua_newtable(lua); + lua_pushstring(lua,"err"); + lua_pushstring(lua, final_msg); + lua_settable(lua,-3); + + sdsfree(msg); + sdsfree(final_msg); +} + +void luaPushError(lua_State *lua, const char *error) { + luaPushErrorBuff(lua, sdsnew(error)); +} + +/* In case the error set into the Lua stack by luaPushError() was generated + * by the non-error-trapping version of redis.pcall(), which is redis.call(), + * this function will raise the Lua error so that the execution of the + * script will be halted. */ +int luaError(lua_State *lua) { + return lua_error(lua); +} + + +/* --------------------------------------------------------------------------- + * Lua reply to Redis reply conversion functions. + * ------------------------------------------------------------------------- */ + +/* Reply to client 'c' converting the top element in the Lua stack to a + * Redis reply. As a side effect the element is consumed from the stack. */ +static void luaReplyToRedisReply(client *c, client* script_client, lua_State *lua) { + int t = lua_type(lua,-1); + + if (!lua_checkstack(lua, 4)) { + /* Increase the Lua stack if needed to make sure there is enough room + * to push 4 elements to the stack. On failure, return error. + * Notice that we need, in the worst case, 4 elements because returning a map might + * require push 4 elements to the Lua stack.*/ + addReplyErrorFormat(c, "reached lua stack limit"); + lua_pop(lua,1); /* pop the element from the stack */ + return; + } + + switch(t) { + case LUA_TSTRING: + addReplyBulkCBuffer(c,(char*)lua_tostring(lua,-1),lua_strlen(lua,-1)); + break; + case LUA_TBOOLEAN: + if (script_client->resp == 2) + addReply(c,lua_toboolean(lua,-1) ? shared.cone : + shared.null[c->resp]); + else + addReplyBool(c,lua_toboolean(lua,-1)); + break; + case LUA_TNUMBER: + addReplyLongLong(c,(long long)lua_tonumber(lua,-1)); + break; + case LUA_TTABLE: + /* We need to check if it is an array, an error, or a status reply. + * Error are returned as a single element table with 'err' field. + * Status replies are returned as single element table with 'ok' + * field. */ + + /* Handle error reply. */ + /* we took care of the stack size on function start */ + lua_pushstring(lua,"err"); + lua_rawget(lua,-2); + t = lua_type(lua,-1); + if (t == LUA_TSTRING) { + lua_pop(lua, 1); /* pop the error message, we will use luaExtractErrorInformation to get error information */ + errorInfo err_info = {0}; + luaExtractErrorInformation(lua, &err_info); + addReplyErrorFormatEx(c, + err_info.ignore_err_stats_update? ERR_REPLY_FLAG_NO_STATS_UPDATE: 0, + "-%s", + err_info.msg); + luaErrorInformationDiscard(&err_info); + lua_pop(lua,1); /* pop the result table */ + return; + } + lua_pop(lua,1); /* Discard field name pushed before. */ + + /* Handle status reply. */ + lua_pushstring(lua,"ok"); + lua_rawget(lua,-2); + t = lua_type(lua,-1); + if (t == LUA_TSTRING) { + sds ok = sdsnew(lua_tostring(lua,-1)); + sdsmapchars(ok,"\r\n"," ",2); + addReplyStatusLength(c, ok, sdslen(ok)); + sdsfree(ok); + lua_pop(lua,2); + return; + } + lua_pop(lua,1); /* Discard field name pushed before. */ + + /* Handle double reply. */ + lua_pushstring(lua,"double"); + lua_rawget(lua,-2); + t = lua_type(lua,-1); + if (t == LUA_TNUMBER) { + addReplyDouble(c,lua_tonumber(lua,-1)); + lua_pop(lua,2); + return; + } + lua_pop(lua,1); /* Discard field name pushed before. */ + + /* Handle big number reply. */ + lua_pushstring(lua,"big_number"); + lua_rawget(lua,-2); + t = lua_type(lua,-1); + if (t == LUA_TSTRING) { + sds big_num = sdsnewlen(lua_tostring(lua,-1), lua_strlen(lua,-1)); + sdsmapchars(big_num,"\r\n"," ",2); + addReplyBigNum(c,big_num,sdslen(big_num)); + sdsfree(big_num); + lua_pop(lua,2); + return; + } + lua_pop(lua,1); /* Discard field name pushed before. */ + + /* Handle verbatim reply. */ + lua_pushstring(lua,"verbatim_string"); + lua_rawget(lua,-2); + t = lua_type(lua,-1); + if (t == LUA_TTABLE) { + lua_pushstring(lua,"format"); + lua_rawget(lua,-2); + t = lua_type(lua,-1); + if (t == LUA_TSTRING){ + char* format = (char*)lua_tostring(lua,-1); + lua_pushstring(lua,"string"); + lua_rawget(lua,-3); + t = lua_type(lua,-1); + if (t == LUA_TSTRING){ + size_t len; + char* str = (char*)lua_tolstring(lua,-1,&len); + addReplyVerbatim(c, str, len, format); + lua_pop(lua,4); + return; + } + lua_pop(lua,1); + } + lua_pop(lua,1); + } + lua_pop(lua,1); /* Discard field name pushed before. */ + + /* Handle map reply. */ + lua_pushstring(lua,"map"); + lua_rawget(lua,-2); + t = lua_type(lua,-1); + if (t == LUA_TTABLE) { + int maplen = 0; + void *replylen = addReplyDeferredLen(c); + /* we took care of the stack size on function start */ + lua_pushnil(lua); /* Use nil to start iteration. */ + while (lua_next(lua,-2)) { + /* Stack now: table, key, value */ + lua_pushvalue(lua,-2); /* Dup key before consuming. */ + luaReplyToRedisReply(c, script_client, lua); /* Return key. */ + luaReplyToRedisReply(c, script_client, lua); /* Return value. */ + /* Stack now: table, key. */ + maplen++; + } + setDeferredMapLen(c,replylen,maplen); + lua_pop(lua,2); + return; + } + lua_pop(lua,1); /* Discard field name pushed before. */ + + /* Handle set reply. */ + lua_pushstring(lua,"set"); + lua_rawget(lua,-2); + t = lua_type(lua,-1); + if (t == LUA_TTABLE) { + int setlen = 0; + void *replylen = addReplyDeferredLen(c); + /* we took care of the stack size on function start */ + lua_pushnil(lua); /* Use nil to start iteration. */ + while (lua_next(lua,-2)) { + /* Stack now: table, key, true */ + lua_pop(lua,1); /* Discard the boolean value. */ + lua_pushvalue(lua,-1); /* Dup key before consuming. */ + luaReplyToRedisReply(c, script_client, lua); /* Return key. */ + /* Stack now: table, key. */ + setlen++; + } + setDeferredSetLen(c,replylen,setlen); + lua_pop(lua,2); + return; + } + lua_pop(lua,1); /* Discard field name pushed before. */ + + /* Handle the array reply. */ + void *replylen = addReplyDeferredLen(c); + int j = 1, mbulklen = 0; + while(1) { + /* we took care of the stack size on function start */ + lua_pushnumber(lua,j++); + lua_rawget(lua,-2); + t = lua_type(lua,-1); + if (t == LUA_TNIL) { + lua_pop(lua,1); + break; + } + luaReplyToRedisReply(c, script_client, lua); + mbulklen++; + } + setDeferredArrayLen(c,replylen,mbulklen); + break; + default: + addReplyNull(c); + } + lua_pop(lua,1); +} + +/* --------------------------------------------------------------------------- + * Lua redis.* functions implementations. + * ------------------------------------------------------------------------- */ +void freeLuaRedisArgv(robj **argv, int argc, int argv_len); + +/* Cached argv array across calls. */ +static robj **lua_argv = NULL; +static int lua_argv_size = 0; + +/* Cache of recently used small arguments to avoid malloc calls. */ +#define LUA_CMD_OBJCACHE_SIZE 32 +#define LUA_CMD_OBJCACHE_MAX_LEN 64 +static robj *lua_args_cached_objects[LUA_CMD_OBJCACHE_SIZE]; +static size_t lua_args_cached_objects_len[LUA_CMD_OBJCACHE_SIZE]; + +static robj **luaArgsToRedisArgv(lua_State *lua, int *argc, int *argv_len) { + int j; + /* Require at least one argument */ + *argc = lua_gettop(lua); + if (*argc == 0) { + luaPushError(lua, "Please specify at least one argument for this redis lib call"); + return NULL; + } + + /* Build the arguments vector (reuse a cached argv from last call) */ + if (lua_argv_size < *argc) { + lua_argv = zrealloc(lua_argv,sizeof(robj*)* *argc); + lua_argv_size = *argc; + } + *argv_len = lua_argv_size; + + for (j = 0; j < *argc; j++) { + char *obj_s; + size_t obj_len; + char dbuf[64]; + + if (lua_type(lua,j+1) == LUA_TNUMBER) { + /* We can't use lua_tolstring() for number -> string conversion + * since Lua uses a format specifier that loses precision. */ + lua_Number num = lua_tonumber(lua,j+1); + + obj_len = snprintf(dbuf,sizeof(dbuf),"%.17g",(double)num); + obj_s = dbuf; + } else { + obj_s = (char*)lua_tolstring(lua,j+1,&obj_len); + if (obj_s == NULL) break; /* Not a string. */ + } + /* Try to use a cached object. */ + if (j < LUA_CMD_OBJCACHE_SIZE && lua_args_cached_objects[j] && + lua_args_cached_objects_len[j] >= obj_len) + { + sds s = lua_args_cached_objects[j]->ptr; + lua_argv[j] = lua_args_cached_objects[j]; + lua_args_cached_objects[j] = NULL; + memcpy(s,obj_s,obj_len+1); + sdssetlen(s, obj_len); + } else { + lua_argv[j] = createStringObject(obj_s, obj_len); + } + } + + /* Pop all arguments from the stack, we do not need them anymore + * and this way we guaranty we will have room on the stack for the result. */ + lua_pop(lua, *argc); + + /* Check if one of the arguments passed by the Lua script + * is not a string or an integer (lua_isstring() return true for + * integers as well). */ + if (j != *argc) { + freeLuaRedisArgv(lua_argv, j, lua_argv_size); + luaPushError(lua, "Lua redis lib command arguments must be strings or integers"); + return NULL; + } + + return lua_argv; +} + +void freeLuaRedisArgv(robj **argv, int argc, int argv_len) { + int j; + for (j = 0; j < argc; j++) { + robj *o = argv[j]; + + /* Try to cache the object in the lua_args_cached_objects array. + * The object must be small, SDS-encoded, and with refcount = 1 + * (we must be the only owner) for us to cache it. */ + if (j < LUA_CMD_OBJCACHE_SIZE && + o->refcount == 1 && + (o->encoding == OBJ_ENCODING_RAW || + o->encoding == OBJ_ENCODING_EMBSTR) && + sdslen(o->ptr) <= LUA_CMD_OBJCACHE_MAX_LEN) + { + sds s = o->ptr; + if (lua_args_cached_objects[j]) decrRefCount(lua_args_cached_objects[j]); + lua_args_cached_objects[j] = o; + lua_args_cached_objects_len[j] = sdsalloc(s); + } else { + decrRefCount(o); + } + } + if (argv != lua_argv || argv_len != lua_argv_size) { + /* The command changed argv, scrap the cache and start over. */ + zfree(argv); + lua_argv = NULL; + lua_argv_size = 0; + } +} + +static int luaRedisGenericCommand(lua_State *lua, int raise_error) { + int j; + scriptRunCtx* rctx = luaGetFromRegistry(lua, REGISTRY_RUN_CTX_NAME); + if (!rctx) { + luaPushError(lua, "redis.call/pcall can only be called inside a script invocation"); + return luaError(lua); + } + sds err = NULL; + client* c = rctx->c; + sds reply; + + c->argv = luaArgsToRedisArgv(lua, &c->argc, &c->argv_len); + if (c->argv == NULL) { + return raise_error ? luaError(lua) : 1; + } + + static int inuse = 0; /* Recursive calls detection. */ + + /* By using Lua debug hooks it is possible to trigger a recursive call + * to luaRedisGenericCommand(), which normally should never happen. + * To make this function reentrant is futile and makes it slower, but + * we should at least detect such a misuse, and abort. */ + if (inuse) { + char *recursion_warning = + "luaRedisGenericCommand() recursive call detected. " + "Are you doing funny stuff with Lua debug hooks?"; + serverLog(LL_WARNING,"%s",recursion_warning); + luaPushError(lua,recursion_warning); + return 1; + } + inuse++; + + /* Log the command if debugging is active. */ + if (ldbIsEnabled()) { + sds cmdlog = sdsnew("<redis>"); + for (j = 0; j < c->argc; j++) { + if (j == 10) { + cmdlog = sdscatprintf(cmdlog," ... (%d more)", + c->argc-j-1); + break; + } else { + cmdlog = sdscatlen(cmdlog," ",1); + cmdlog = sdscatsds(cmdlog,c->argv[j]->ptr); + } + } + ldbLog(cmdlog); + } + + scriptCall(rctx, &err); + if (err) { + luaPushError(lua, err); + sdsfree(err); + /* push a field indicate to ignore updating the stats on this error + * because it was already updated when executing the command. */ + lua_pushstring(lua,"ignore_error_stats_update"); + lua_pushboolean(lua, 1); + lua_settable(lua,-3); + goto cleanup; + } + + /* Convert the result of the Redis command into a suitable Lua type. + * The first thing we need is to create a single string from the client + * output buffers. */ + if (listLength(c->reply) == 0 && (size_t)c->bufpos < c->buf_usable_size) { + /* This is a fast path for the common case of a reply inside the + * client static buffer. Don't create an SDS string but just use + * the client buffer directly. */ + c->buf[c->bufpos] = '\0'; + reply = c->buf; + c->bufpos = 0; + } else { + reply = sdsnewlen(c->buf,c->bufpos); + c->bufpos = 0; + while(listLength(c->reply)) { + clientReplyBlock *o = listNodeValue(listFirst(c->reply)); + + reply = sdscatlen(reply,o->buf,o->used); + listDelNode(c->reply,listFirst(c->reply)); + } + } + if (raise_error && reply[0] != '-') raise_error = 0; + redisProtocolToLuaType(lua,reply); + + /* If the debugger is active, log the reply from Redis. */ + if (ldbIsEnabled()) + ldbLogRedisReply(reply); + + if (reply != c->buf) sdsfree(reply); + c->reply_bytes = 0; + +cleanup: + /* Clean up. Command code may have changed argv/argc so we use the + * argv/argc of the client instead of the local variables. */ + freeLuaRedisArgv(c->argv, c->argc, c->argv_len); + c->argc = c->argv_len = 0; + c->user = NULL; + c->argv = NULL; + freeClientArgv(c); + inuse--; + + if (raise_error) { + /* If we are here we should have an error in the stack, in the + * form of a table with an "err" field. Extract the string to + * return the plain error. */ + return luaError(lua); + } + return 1; +} + +/* Our implementation to lua pcall. + * We need this implementation for backward + * comparability with older Redis versions. + * + * On Redis 7, the error object is a table, + * compare to older version where the error + * object is a string. To keep backward + * comparability we catch the table object + * and just return the error message. */ +static int luaRedisPcall(lua_State *lua) { + int argc = lua_gettop(lua); + lua_pushboolean(lua, 1); /* result place holder */ + lua_insert(lua, 1); + if (lua_pcall(lua, argc - 1, LUA_MULTRET, 0)) { + /* Error */ + lua_remove(lua, 1); /* remove the result place holder, now we have room for at least one element */ + if (lua_istable(lua, -1)) { + lua_getfield(lua, -1, "err"); + if (lua_isstring(lua, -1)) { + lua_replace(lua, -2); /* replace the error message with the table */ + } + } + lua_pushboolean(lua, 0); /* push result */ + lua_insert(lua, 1); + } + return lua_gettop(lua); + +} + +/* redis.call() */ +static int luaRedisCallCommand(lua_State *lua) { + return luaRedisGenericCommand(lua,1); +} + +/* redis.pcall() */ +static int luaRedisPCallCommand(lua_State *lua) { + return luaRedisGenericCommand(lua,0); +} + +/* This adds redis.sha1hex(string) to Lua scripts using the same hashing + * function used for sha1ing lua scripts. */ +static int luaRedisSha1hexCommand(lua_State *lua) { + int argc = lua_gettop(lua); + char digest[41]; + size_t len; + char *s; + + if (argc != 1) { + luaPushError(lua, "wrong number of arguments"); + return luaError(lua); + } + + s = (char*)lua_tolstring(lua,1,&len); + sha1hex(digest,s,len); + lua_pushstring(lua,digest); + return 1; +} + +/* Returns a table with a single field 'field' set to the string value + * passed as argument. This helper function is handy when returning + * a Redis Protocol error or status reply from Lua: + * + * return redis.error_reply("ERR Some Error") + * return redis.status_reply("ERR Some Error") + */ +static int luaRedisReturnSingleFieldTable(lua_State *lua, char *field) { + if (lua_gettop(lua) != 1 || lua_type(lua,-1) != LUA_TSTRING) { + luaPushError(lua, "wrong number or type of arguments"); + return 1; + } + + lua_newtable(lua); + lua_pushstring(lua, field); + lua_pushvalue(lua, -3); + lua_settable(lua, -3); + return 1; +} + +/* redis.error_reply() */ +static int luaRedisErrorReplyCommand(lua_State *lua) { + if (lua_gettop(lua) != 1 || lua_type(lua,-1) != LUA_TSTRING) { + luaPushError(lua, "wrong number or type of arguments"); + return 1; + } + + /* add '-' if not exists */ + const char *err = lua_tostring(lua, -1); + sds err_buff = NULL; + if (err[0] != '-') { + err_buff = sdscatfmt(sdsempty(), "-%s", err); + } else { + err_buff = sdsnew(err); + } + luaPushErrorBuff(lua, err_buff); + return 1; +} + +/* redis.status_reply() */ +static int luaRedisStatusReplyCommand(lua_State *lua) { + return luaRedisReturnSingleFieldTable(lua,"ok"); +} + +/* redis.set_repl() + * + * Set the propagation of write commands executed in the context of the + * script to on/off for AOF and slaves. */ +static int luaRedisSetReplCommand(lua_State *lua) { + int flags, argc = lua_gettop(lua); + + scriptRunCtx* rctx = luaGetFromRegistry(lua, REGISTRY_RUN_CTX_NAME); + if (!rctx) { + luaPushError(lua, "redis.set_repl can only be called inside a script invocation"); + return luaError(lua); + } + + if (argc != 1) { + luaPushError(lua, "redis.set_repl() requires two arguments."); + return luaError(lua); + } + + flags = lua_tonumber(lua,-1); + if ((flags & ~(PROPAGATE_AOF|PROPAGATE_REPL)) != 0) { + luaPushError(lua, "Invalid replication flags. Use REPL_AOF, REPL_REPLICA, REPL_ALL or REPL_NONE."); + return luaError(lua); + } + + scriptSetRepl(rctx, flags); + return 0; +} + +/* redis.acl_check_cmd() + * + * Checks ACL permissions for given command for the current user. */ +static int luaRedisAclCheckCmdPermissionsCommand(lua_State *lua) { + scriptRunCtx* rctx = luaGetFromRegistry(lua, REGISTRY_RUN_CTX_NAME); + if (!rctx) { + luaPushError(lua, "redis.acl_check_cmd can only be called inside a script invocation"); + return luaError(lua); + } + int raise_error = 0; + + int argc, argv_len; + robj **argv = luaArgsToRedisArgv(lua, &argc, &argv_len); + + /* Require at least one argument */ + if (argv == NULL) return luaError(lua); + + /* Find command */ + struct redisCommand *cmd; + if ((cmd = lookupCommand(argv, argc)) == NULL) { + luaPushError(lua, "Invalid command passed to redis.acl_check_cmd()"); + raise_error = 1; + } else { + int keyidxptr; + if (ACLCheckAllUserCommandPerm(rctx->original_client->user, cmd, argv, argc, &keyidxptr) != ACL_OK) { + lua_pushboolean(lua, 0); + } else { + lua_pushboolean(lua, 1); + } + } + + freeLuaRedisArgv(argv, argc, argv_len); + if (raise_error) + return luaError(lua); + else + return 1; +} + + +/* redis.log() */ +static int luaLogCommand(lua_State *lua) { + int j, argc = lua_gettop(lua); + int level; + sds log; + + if (argc < 2) { + luaPushError(lua, "redis.log() requires two arguments or more."); + return luaError(lua); + } else if (!lua_isnumber(lua,-argc)) { + luaPushError(lua, "First argument must be a number (log level)."); + return luaError(lua); + } + level = lua_tonumber(lua,-argc); + if (level < LL_DEBUG || level > LL_WARNING) { + luaPushError(lua, "Invalid debug level."); + return luaError(lua); + } + if (level < server.verbosity) return 0; + + /* Glue together all the arguments */ + log = sdsempty(); + for (j = 1; j < argc; j++) { + size_t len; + char *s; + + s = (char*)lua_tolstring(lua,(-argc)+j,&len); + if (s) { + if (j != 1) log = sdscatlen(log," ",1); + log = sdscatlen(log,s,len); + } + } + serverLogRaw(level,log); + sdsfree(log); + return 0; +} + +/* redis.setresp() */ +static int luaSetResp(lua_State *lua) { + scriptRunCtx* rctx = luaGetFromRegistry(lua, REGISTRY_RUN_CTX_NAME); + if (!rctx) { + luaPushError(lua, "redis.setresp can only be called inside a script invocation"); + return luaError(lua); + } + int argc = lua_gettop(lua); + + if (argc != 1) { + luaPushError(lua, "redis.setresp() requires one argument."); + return luaError(lua); + } + + int resp = lua_tonumber(lua,-argc); + if (resp != 2 && resp != 3) { + luaPushError(lua, "RESP version must be 2 or 3."); + return luaError(lua); + } + scriptSetResp(rctx, resp); + return 0; +} + +/* --------------------------------------------------------------------------- + * Lua engine initialization and reset. + * ------------------------------------------------------------------------- */ + +static void luaLoadLib(lua_State *lua, const char *libname, lua_CFunction luafunc) { + lua_pushcfunction(lua, luafunc); + lua_pushstring(lua, libname); + lua_call(lua, 1, 0); +} + +LUALIB_API int (luaopen_cjson) (lua_State *L); +LUALIB_API int (luaopen_struct) (lua_State *L); +LUALIB_API int (luaopen_cmsgpack) (lua_State *L); +LUALIB_API int (luaopen_bit) (lua_State *L); + +static void luaLoadLibraries(lua_State *lua) { + luaLoadLib(lua, "", luaopen_base); + luaLoadLib(lua, LUA_TABLIBNAME, luaopen_table); + luaLoadLib(lua, LUA_STRLIBNAME, luaopen_string); + luaLoadLib(lua, LUA_MATHLIBNAME, luaopen_math); + luaLoadLib(lua, LUA_DBLIBNAME, luaopen_debug); + luaLoadLib(lua, "cjson", luaopen_cjson); + luaLoadLib(lua, "struct", luaopen_struct); + luaLoadLib(lua, "cmsgpack", luaopen_cmsgpack); + luaLoadLib(lua, "bit", luaopen_bit); + +#if 0 /* Stuff that we don't load currently, for sandboxing concerns. */ + luaLoadLib(lua, LUA_LOADLIBNAME, luaopen_package); + luaLoadLib(lua, LUA_OSLIBNAME, luaopen_os); +#endif +} + +/* Return sds of the string value located on stack at the given index. + * Return NULL if the value is not a string. */ +sds luaGetStringSds(lua_State *lua, int index) { + if (!lua_isstring(lua, index)) { + return NULL; + } + + size_t len; + const char *str = lua_tolstring(lua, index, &len); + sds str_sds = sdsnewlen(str, len); + return str_sds; +} + +static int luaProtectedTableError(lua_State *lua) { + int argc = lua_gettop(lua); + if (argc != 2) { + serverLog(LL_WARNING, "malicious code trying to call luaProtectedTableError with wrong arguments"); + luaL_error(lua, "Wrong number of arguments to luaProtectedTableError"); + } + if (!lua_isstring(lua, -1) && !lua_isnumber(lua, -1)) { + luaL_error(lua, "Second argument to luaProtectedTableError must be a string or number"); + } + const char *variable_name = lua_tostring(lua, -1); + luaL_error(lua, "Script attempted to access nonexistent global variable '%s'", variable_name); + return 0; +} + +/* Set a special metatable on the table on the top of the stack. + * The metatable will raise an error if the user tries to fetch + * an un-existing value. + * + * The function assumes the Lua stack have a least enough + * space to push 2 element, its up to the caller to verify + * this before calling this function. */ +void luaSetErrorMetatable(lua_State *lua) { + lua_newtable(lua); /* push metatable */ + lua_pushcfunction(lua, luaProtectedTableError); /* push get error handler */ + lua_setfield(lua, -2, "__index"); + lua_setmetatable(lua, -2); +} + +static int luaNewIndexAllowList(lua_State *lua) { + int argc = lua_gettop(lua); + if (argc != 3) { + serverLog(LL_WARNING, "malicious code trying to call luaProtectedTableError with wrong arguments"); + luaL_error(lua, "Wrong number of arguments to luaNewIndexAllowList"); + } + if (!lua_istable(lua, -3)) { + luaL_error(lua, "first argument to luaNewIndexAllowList must be a table"); + } + if (!lua_isstring(lua, -2) && !lua_isnumber(lua, -2)) { + luaL_error(lua, "Second argument to luaNewIndexAllowList must be a string or number"); + } + const char *variable_name = lua_tostring(lua, -2); + /* check if the key is in our allow list */ + + char ***allow_l = allow_lists; + for (; *allow_l ; ++allow_l){ + char **c = *allow_l; + for (; *c ; ++c) { + if (strcmp(*c, variable_name) == 0) { + break; + } + } + if (*c) { + break; + } + } + if (!*allow_l) { + /* Search the value on the back list, if its there we know that it was removed + * on purpose and there is no need to print a warning. */ + char **c = deny_list; + for ( ; *c ; ++c) { + if (strcmp(*c, variable_name) == 0) { + break; + } + } + if (!*c) { + serverLog(LL_WARNING, "A key '%s' was added to Lua globals which is not on the globals allow list nor listed on the deny list.", variable_name); + } + } else { + lua_rawset(lua, -3); + } + return 0; +} + +/* Set a metatable with '__newindex' function that verify that + * the new index appears on our globals while list. + * + * The metatable is set on the table which located on the top + * of the stack. + */ +void luaSetAllowListProtection(lua_State *lua) { + lua_newtable(lua); /* push metatable */ + lua_pushcfunction(lua, luaNewIndexAllowList); /* push get error handler */ + lua_setfield(lua, -2, "__newindex"); + lua_setmetatable(lua, -2); +} + +/* Set the readonly flag on the table located on the top of the stack + * and recursively call this function on each table located on the original + * table. Also, recursively call this function on the metatables.*/ +void luaSetTableProtectionRecursively(lua_State *lua) { + /* This protect us from a loop in case we already visited the table + * For example, globals has '_G' key which is pointing back to globals. */ + if (lua_isreadonlytable(lua, -1)) { + return; + } + + /* protect the current table */ + lua_enablereadonlytable(lua, -1, 1); + + lua_checkstack(lua, 2); + lua_pushnil(lua); /* Use nil to start iteration. */ + while (lua_next(lua,-2)) { + /* Stack now: table, key, value */ + if (lua_istable(lua, -1)) { + luaSetTableProtectionRecursively(lua); + } + lua_pop(lua, 1); + } + + /* protect the metatable if exists */ + if (lua_getmetatable(lua, -1)) { + luaSetTableProtectionRecursively(lua); + lua_pop(lua, 1); /* pop the metatable */ + } +} + +void luaRegisterVersion(lua_State* lua) { + lua_pushstring(lua,"REDIS_VERSION_NUM"); + lua_pushnumber(lua,REDIS_VERSION_NUM); + lua_settable(lua,-3); + + lua_pushstring(lua,"REDIS_VERSION"); + lua_pushstring(lua,REDIS_VERSION); + lua_settable(lua,-3); +} + +void luaRegisterLogFunction(lua_State* lua) { + /* redis.log and log levels. */ + lua_pushstring(lua,"log"); + lua_pushcfunction(lua,luaLogCommand); + lua_settable(lua,-3); + + lua_pushstring(lua,"LOG_DEBUG"); + lua_pushnumber(lua,LL_DEBUG); + lua_settable(lua,-3); + + lua_pushstring(lua,"LOG_VERBOSE"); + lua_pushnumber(lua,LL_VERBOSE); + lua_settable(lua,-3); + + lua_pushstring(lua,"LOG_NOTICE"); + lua_pushnumber(lua,LL_NOTICE); + lua_settable(lua,-3); + + lua_pushstring(lua,"LOG_WARNING"); + lua_pushnumber(lua,LL_WARNING); + lua_settable(lua,-3); +} + +void luaRegisterRedisAPI(lua_State* lua) { + lua_pushvalue(lua, LUA_GLOBALSINDEX); + luaSetAllowListProtection(lua); + lua_pop(lua, 1); + + luaLoadLibraries(lua); + + lua_pushcfunction(lua,luaRedisPcall); + lua_setglobal(lua, "pcall"); + + /* Register the redis commands table and fields */ + lua_newtable(lua); + + /* redis.call */ + lua_pushstring(lua,"call"); + lua_pushcfunction(lua,luaRedisCallCommand); + lua_settable(lua,-3); + + /* redis.pcall */ + lua_pushstring(lua,"pcall"); + lua_pushcfunction(lua,luaRedisPCallCommand); + lua_settable(lua,-3); + + luaRegisterLogFunction(lua); + + luaRegisterVersion(lua); + + /* redis.setresp */ + lua_pushstring(lua,"setresp"); + lua_pushcfunction(lua,luaSetResp); + lua_settable(lua,-3); + + /* redis.sha1hex */ + lua_pushstring(lua, "sha1hex"); + lua_pushcfunction(lua, luaRedisSha1hexCommand); + lua_settable(lua, -3); + + /* redis.error_reply and redis.status_reply */ + lua_pushstring(lua, "error_reply"); + lua_pushcfunction(lua, luaRedisErrorReplyCommand); + lua_settable(lua, -3); + lua_pushstring(lua, "status_reply"); + lua_pushcfunction(lua, luaRedisStatusReplyCommand); + lua_settable(lua, -3); + + /* redis.set_repl and associated flags. */ + lua_pushstring(lua,"set_repl"); + lua_pushcfunction(lua,luaRedisSetReplCommand); + lua_settable(lua,-3); + + lua_pushstring(lua,"REPL_NONE"); + lua_pushnumber(lua,PROPAGATE_NONE); + lua_settable(lua,-3); + + lua_pushstring(lua,"REPL_AOF"); + lua_pushnumber(lua,PROPAGATE_AOF); + lua_settable(lua,-3); + + lua_pushstring(lua,"REPL_SLAVE"); + lua_pushnumber(lua,PROPAGATE_REPL); + lua_settable(lua,-3); + + lua_pushstring(lua,"REPL_REPLICA"); + lua_pushnumber(lua,PROPAGATE_REPL); + lua_settable(lua,-3); + + lua_pushstring(lua,"REPL_ALL"); + lua_pushnumber(lua,PROPAGATE_AOF|PROPAGATE_REPL); + lua_settable(lua,-3); + + /* redis.acl_check_cmd */ + lua_pushstring(lua,"acl_check_cmd"); + lua_pushcfunction(lua,luaRedisAclCheckCmdPermissionsCommand); + lua_settable(lua,-3); + + /* Finally set the table as 'redis' global var. */ + lua_setglobal(lua,REDIS_API_NAME); + + /* Replace math.random and math.randomseed with our implementations. */ + lua_getglobal(lua,"math"); + + lua_pushstring(lua,"random"); + lua_pushcfunction(lua,redis_math_random); + lua_settable(lua,-3); + + lua_pushstring(lua,"randomseed"); + lua_pushcfunction(lua,redis_math_randomseed); + lua_settable(lua,-3); + + lua_setglobal(lua,"math"); +} + +/* Set an array of Redis String Objects as a Lua array (table) stored into a + * global variable. */ +static void luaCreateArray(lua_State *lua, robj **elev, int elec) { + int j; + + lua_newtable(lua); + for (j = 0; j < elec; j++) { + lua_pushlstring(lua,(char*)elev[j]->ptr,sdslen(elev[j]->ptr)); + lua_rawseti(lua,-2,j+1); + } +} + +/* --------------------------------------------------------------------------- + * Redis provided math.random + * ------------------------------------------------------------------------- */ + +/* We replace math.random() with our implementation that is not affected + * by specific libc random() implementations and will output the same sequence + * (for the same seed) in every arch. */ + +/* The following implementation is the one shipped with Lua itself but with + * rand() replaced by redisLrand48(). */ +static int redis_math_random (lua_State *L) { + scriptRunCtx* rctx = luaGetFromRegistry(L, REGISTRY_RUN_CTX_NAME); + if (!rctx) { + return luaL_error(L, "math.random can only be called inside a script invocation"); + } + + /* the `%' avoids the (rare) case of r==1, and is needed also because on + some systems (SunOS!) `rand()' may return a value larger than RAND_MAX */ + lua_Number r = (lua_Number)(redisLrand48()%REDIS_LRAND48_MAX) / + (lua_Number)REDIS_LRAND48_MAX; + switch (lua_gettop(L)) { /* check number of arguments */ + case 0: { /* no arguments */ + lua_pushnumber(L, r); /* Number between 0 and 1 */ + break; + } + case 1: { /* only upper limit */ + int u = luaL_checkint(L, 1); + luaL_argcheck(L, 1<=u, 1, "interval is empty"); + lua_pushnumber(L, floor(r*u)+1); /* int between 1 and `u' */ + break; + } + case 2: { /* lower and upper limits */ + int l = luaL_checkint(L, 1); + int u = luaL_checkint(L, 2); + luaL_argcheck(L, l<=u, 2, "interval is empty"); + lua_pushnumber(L, floor(r*(u-l+1))+l); /* int between `l' and `u' */ + break; + } + default: return luaL_error(L, "wrong number of arguments"); + } + return 1; +} + +static int redis_math_randomseed (lua_State *L) { + scriptRunCtx* rctx = luaGetFromRegistry(L, REGISTRY_RUN_CTX_NAME); + if (!rctx) { + return luaL_error(L, "math.randomseed can only be called inside a script invocation"); + } + redisSrand48(luaL_checkint(L, 1)); + return 0; +} + +/* This is the Lua script "count" hook that we use to detect scripts timeout. */ +static void luaMaskCountHook(lua_State *lua, lua_Debug *ar) { + UNUSED(ar); + scriptRunCtx* rctx = luaGetFromRegistry(lua, REGISTRY_RUN_CTX_NAME); + if (scriptInterrupt(rctx) == SCRIPT_KILL) { + serverLog(LL_WARNING,"Lua script killed by user with SCRIPT KILL."); + + /* + * Set the hook to invoke all the time so the user + * will not be able to catch the error with pcall and invoke + * pcall again which will prevent the script from ever been killed + */ + lua_sethook(lua, luaMaskCountHook, LUA_MASKLINE, 0); + + luaPushError(lua,"Script killed by user with SCRIPT KILL..."); + luaError(lua); + } +} + +void luaErrorInformationDiscard(errorInfo *err_info) { + if (err_info->msg) sdsfree(err_info->msg); + if (err_info->source) sdsfree(err_info->source); + if (err_info->line) sdsfree(err_info->line); +} + +void luaExtractErrorInformation(lua_State *lua, errorInfo *err_info) { + if (lua_isstring(lua, -1)) { + err_info->msg = sdscatfmt(sdsempty(), "ERR %s", lua_tostring(lua, -1)); + err_info->line = NULL; + err_info->source = NULL; + err_info->ignore_err_stats_update = 0; + } + + lua_getfield(lua, -1, "err"); + if (lua_isstring(lua, -1)) { + err_info->msg = sdsnew(lua_tostring(lua, -1)); + } + lua_pop(lua, 1); + + lua_getfield(lua, -1, "source"); + if (lua_isstring(lua, -1)) { + err_info->source = sdsnew(lua_tostring(lua, -1)); + } + lua_pop(lua, 1); + + lua_getfield(lua, -1, "line"); + if (lua_isstring(lua, -1)) { + err_info->line = sdsnew(lua_tostring(lua, -1)); + } + lua_pop(lua, 1); + + lua_getfield(lua, -1, "ignore_error_stats_update"); + if (lua_isboolean(lua, -1)) { + err_info->ignore_err_stats_update = lua_toboolean(lua, -1); + } + lua_pop(lua, 1); +} + +void luaCallFunction(scriptRunCtx* run_ctx, lua_State *lua, robj** keys, size_t nkeys, robj** args, size_t nargs, int debug_enabled) { + client* c = run_ctx->original_client; + int delhook = 0; + + /* We must set it before we set the Lua hook, theoretically the + * Lua hook might be called wheneven we run any Lua instruction + * such as 'luaSetGlobalArray' and we want the run_ctx to be available + * each time the Lua hook is invoked. */ + luaSaveOnRegistry(lua, REGISTRY_RUN_CTX_NAME, run_ctx); + + if (server.busy_reply_threshold > 0 && !debug_enabled) { + lua_sethook(lua,luaMaskCountHook,LUA_MASKCOUNT,100000); + delhook = 1; + } else if (debug_enabled) { + lua_sethook(lua,luaLdbLineHook,LUA_MASKLINE|LUA_MASKCOUNT,100000); + delhook = 1; + } + + /* Populate the argv and keys table accordingly to the arguments that + * EVAL received. */ + luaCreateArray(lua,keys,nkeys); + /* On eval, keys and arguments are globals. */ + if (run_ctx->flags & SCRIPT_EVAL_MODE){ + /* open global protection to set KEYS */ + lua_enablereadonlytable(lua, LUA_GLOBALSINDEX, 0); + lua_setglobal(lua,"KEYS"); + lua_enablereadonlytable(lua, LUA_GLOBALSINDEX, 1); + } + luaCreateArray(lua,args,nargs); + if (run_ctx->flags & SCRIPT_EVAL_MODE){ + /* open global protection to set ARGV */ + lua_enablereadonlytable(lua, LUA_GLOBALSINDEX, 0); + lua_setglobal(lua,"ARGV"); + lua_enablereadonlytable(lua, LUA_GLOBALSINDEX, 1); + } + + /* At this point whether this script was never seen before or if it was + * already defined, we can call it. + * On eval mode, we have zero arguments and expect a single return value. + * In addition the error handler is located on position -2 on the Lua stack. + * On function mode, we pass 2 arguments (the keys and args tables), + * and the error handler is located on position -4 (stack: error_handler, callback, keys, args) */ + int err; + if (run_ctx->flags & SCRIPT_EVAL_MODE) { + err = lua_pcall(lua,0,1,-2); + } else { + err = lua_pcall(lua,2,1,-4); + } + + /* Call the Lua garbage collector from time to time to avoid a + * full cycle performed by Lua, which adds too latency. + * + * The call is performed every LUA_GC_CYCLE_PERIOD executed commands + * (and for LUA_GC_CYCLE_PERIOD collection steps) because calling it + * for every command uses too much CPU. */ + #define LUA_GC_CYCLE_PERIOD 50 + { + static long gc_count = 0; + + gc_count++; + if (gc_count == LUA_GC_CYCLE_PERIOD) { + lua_gc(lua,LUA_GCSTEP,LUA_GC_CYCLE_PERIOD); + gc_count = 0; + } + } + + if (err) { + /* Error object is a table of the following format: + * {err='<error msg>', source='<source file>', line=<line>} + * We can construct the error message from this information */ + if (!lua_istable(lua, -1)) { + const char *msg = "execution failure"; + if (lua_isstring(lua, -1)) { + msg = lua_tostring(lua, -1); + } + addReplyErrorFormat(c,"Error running script %s, %.100s\n", run_ctx->funcname, msg); + } else { + errorInfo err_info = {0}; + sds final_msg = sdsempty(); + luaExtractErrorInformation(lua, &err_info); + final_msg = sdscatfmt(final_msg, "-%s", + err_info.msg); + if (err_info.line && err_info.source) { + final_msg = sdscatfmt(final_msg, " script: %s, on %s:%s.", + run_ctx->funcname, + err_info.source, + err_info.line); + } + addReplyErrorSdsEx(c, final_msg, err_info.ignore_err_stats_update? ERR_REPLY_FLAG_NO_STATS_UPDATE : 0); + luaErrorInformationDiscard(&err_info); + } + lua_pop(lua,1); /* Consume the Lua error */ + } else { + /* On success convert the Lua return value into Redis protocol, and + * send it to * the client. */ + luaReplyToRedisReply(c, run_ctx->c, lua); /* Convert and consume the reply. */ + } + + /* Perform some cleanup that we need to do both on error and success. */ + if (delhook) lua_sethook(lua,NULL,0,0); /* Disable hook */ + + /* remove run_ctx from registry, its only applicable for the current script. */ + luaSaveOnRegistry(lua, REGISTRY_RUN_CTX_NAME, NULL); +} + +unsigned long luaMemory(lua_State *lua) { + return lua_gc(lua, LUA_GCCOUNT, 0) * 1024LL; +} |