/* This file is part of GNUnet (C) 2006, 2009, 2010 Christian Grothoff (and other contributing authors) GNUnet is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3, or (at your option) any later version. GNUnet 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 General Public License for more details. You should have received a copy of the GNU General Public License along with GNUnet; see the file COPYING. If not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ /** * @file datacache/plugin_datacache_mysql.c * @brief mysql for an implementation of a database backend for the datacache * @author Christian Grothoff * * SETUP INSTRUCTIONS: * * 1) Access mysql as root, *
 *
 *    $ mysql -u root -p
 *
 *    
* and do the following. [You should replace $USER with the username * that will be running the gnunetd process]. * @verbatim CREATE DATABASE gnunet; GRANT select,insert,update,delete,create,alter,drop,create temporary tables ON gnunet.* TO $USER@localhost; SET PASSWORD FOR $USER@localhost=PASSWORD('$the_password_you_like'); FLUSH PRIVILEGES; @endverbatim * 2) In the $HOME directory of $USER, create a ".my.cnf" file * with the following lines * @verbatim [client] user=$USER password=$the_password_you_like @endverbatim * * Thats it -- now you can configure your datastores in GNUnet to * use MySQL. Note that .my.cnf file is a security risk unless its on * a safe partition etc. The $HOME/.my.cnf can of course be a symbolic * link. Even greater security risk can be achieved by setting no * password for $USER. Luckily $USER has only priviledges to mess * up GNUnet's tables, nothing else (unless you give him more, * of course).

* * 3) Still, perhaps you should briefly try if the DB connection * works. First, login as $USER. Then use, * @verbatim $ mysql -u $USER -p $the_password_you_like mysql> use gnunet; @endverbatim * * If you get the message "Database changed" it probably works. * * [If you get "ERROR 2002: Can't connect to local MySQL server * through socket '/tmp/mysql.sock' (2)" it may be resolvable by * "ln -s /var/run/mysqld/mysqld.sock /tmp/mysql.sock" * so there may be some additional trouble depending on your mysql setup.] * * PROBLEMS? * * If you have problems related to the mysql module, your best * friend is probably the mysql manual. The first thing to check * is that mysql is basically operational, that you can connect * to it, create tables, issue queries etc. */ #include "platform.h" #include "gnunet_util_lib.h" #include "gnunet_datacache_plugin.h" #include "gnunet_mysql_lib.h" #include /** * Estimate of the per-entry overhead (including indices). */ #define OVERHEAD ((4*2+4*2+8*2+8*2+sizeof(GNUNET_HashCode)*5+8)) /** * Die with an error message that indicates * a failure of the command 'cmd' with the message given * by strerror(errno). */ #define DIE_MYSQL(cmd, dbh) do { GNUNET_log(GNUNET_ERROR_TYPE__ERROR, _("`%s' failed at %s:%d with error: %s\n"), cmd, __FILE__, __LINE__, mysql_error((dbh)->dbf)); GNUNET_abort(); } while(0); /** * Log an error message at log-level 'level' that indicates * a failure of the command 'cmd' on file 'filename' * with the message given by strerror(errno). */ #define LOG_MYSQL(level, cmd, dbh) do { GNUNET_log(level, _("`%s' failed at %s:%d with error: %s\n"), cmd, __FILE__, __LINE__, mysql_error((dbh)->dbf)); } while(0); /** * Context for all functions in this plugin. */ struct Plugin { /** * Our execution environment. */ struct GNUNET_DATACACHE_PluginEnvironment *env; /** * Handle to the mysql database. */ struct GNUNET_MYSQL_Context *mc; #define SELECT_VALUE_STMT "SELECT value,expire FROM gn080dstore FORCE INDEX (hashidx) WHERE hash=? AND type=? AND expire >= ? LIMIT 1 OFFSET ?" struct GNUNET_MYSQL_StatementHandle *select_value; #define COUNT_VALUE_STMT "SELECT count(*) FROM gn080dstore FORCE INDEX (hashidx) WHERE hash=? AND type=? AND expire >= ?" struct GNUNET_MYSQL_StatementHandle *count_value; #define SELECT_OLD_VALUE_STMT "SELECT hash, vhash, type, value FROM gn080dstore FORCE INDEX (expireidx) ORDER BY puttime ASC LIMIT 1" struct GNUNET_MYSQL_StatementHandle *select_old_value; #define DELETE_VALUE_STMT "DELETE FROM gn080dstore WHERE hash = ? AND vhash = ? AND type = ? AND value = ?" struct GNUNET_MYSQL_StatementHandle *delete_value; #define INSERT_VALUE_STMT "INSERT INTO gn080dstore (type, puttime, expire, hash, vhash, value) "\ "VALUES (?, ?, ?, ?, ?, ?)" struct GNUNET_MYSQL_StatementHandle *insert_value; #define UPDATE_VALUE_STMT "UPDATE gn080dstore FORCE INDEX (allidx) SET puttime=?, expire=? "\ "WHERE hash=? AND vhash=? AND type=?" struct GNUNET_MYSQL_StatementHandle *update_value; }; /** * Create temporary table and prepare statements. * * @param plugin plugin context * @return GNUNET_OK on success */ static int itable (struct Plugin *plugin) { #define MRUNS(a) (GNUNET_OK != GNUNET_MYSQL_statement_run (plugin->mc, a) ) if (MRUNS ("CREATE TEMPORARY TABLE gn080dstore (" " type INT(11) UNSIGNED NOT NULL DEFAULT 0," " puttime BIGINT UNSIGNED NOT NULL DEFAULT 0," " expire BIGINT UNSIGNED NOT NULL DEFAULT 0," " hash BINARY(64) NOT NULL DEFAULT ''," " vhash BINARY(64) NOT NULL DEFAULT ''," " value BLOB NOT NULL DEFAULT ''," " INDEX hashidx (hash(64),type,expire)," " INDEX allidx (hash(64),vhash(64),type)," " INDEX expireidx (puttime)" ") ENGINE=InnoDB") || MRUNS ("SET AUTOCOMMIT = 1")) return GNUNET_SYSERR; #undef MRUNS #define PINIT(a,b) (NULL == (a = GNUNET_MYSQL_statement_prepare (plugin->mc, b))) if (PINIT (plugin->select_value, SELECT_VALUE_STMT) || PINIT (plugin->count_value, COUNT_VALUE_STMT) || PINIT (plugin->select_old_value, SELECT_OLD_VALUE_STMT) || PINIT (plugin->delete_value, DELETE_VALUE_STMT) || PINIT (plugin->insert_value, INSERT_VALUE_STMT) || PINIT (plugin->update_value, UPDATE_VALUE_STMT)) return GNUNET_SYSERR; #undef PINIT return GNUNET_OK; } /** * Store an item in the datastore. * * @param cls closure (our "struct Plugin") * @param key key to store data under * @param size number of bytes in data * @param data data to store * @param type type of the value * @param discard_time when to discard the value in any case * @return 0 on error, number of bytes used otherwise */ static size_t mysql_plugin_put (void *cls, const GNUNET_HashCode * key, size_t size, const char *data, enum GNUNET_BLOCK_Type type, struct GNUNET_TIME_Absolute discard_time) { struct Plugin *plugin = cls; struct GNUNET_TIME_Absolute now; unsigned long k_length; unsigned long h_length; unsigned long v_length; unsigned long long v_now; unsigned long long v_discard_time; unsigned int v_type; GNUNET_HashCode vhash; int ret; if (size > GNUNET_SERVER_MAX_MESSAGE_SIZE) return GNUNET_SYSERR; GNUNET_CRYPTO_hash (data, size, &vhash); now = GNUNET_TIME_absolute_get (); /* first try UPDATE */ h_length = sizeof (GNUNET_HashCode); k_length = sizeof (GNUNET_HashCode); v_length = size; v_type = type; v_now = (unsigned long long) now.abs_value; v_discard_time = (unsigned long long) discard_time.abs_value; if (GNUNET_OK == GNUNET_MYSQL_statement_run_prepared (plugin->mc, plugin->update_value, NULL, MYSQL_TYPE_LONGLONG, &v_now, GNUNET_YES, MYSQL_TYPE_LONGLONG, &v_discard_time, GNUNET_YES, MYSQL_TYPE_BLOB, key, sizeof (GNUNET_HashCode), &k_length, MYSQL_TYPE_BLOB, &vhash, sizeof (GNUNET_HashCode), &h_length, MYSQL_TYPE_LONG, &v_type, GNUNET_YES, -1)) return GNUNET_OK; /* now try INSERT */ h_length = sizeof (GNUNET_HashCode); k_length = sizeof (GNUNET_HashCode); v_length = size; if (GNUNET_OK != (ret = GNUNET_MYSQL_statement_run_prepared (plugin->mc, plugin->insert_value, NULL, MYSQL_TYPE_LONG, &type, GNUNET_YES, MYSQL_TYPE_LONGLONG, &v_now, GNUNET_YES, MYSQL_TYPE_LONGLONG, &v_discard_time, GNUNET_YES, MYSQL_TYPE_BLOB, key, sizeof (GNUNET_HashCode), &k_length, MYSQL_TYPE_BLOB, &vhash, sizeof (GNUNET_HashCode), &h_length, MYSQL_TYPE_BLOB, data, (unsigned long) size, &v_length, -1))) { if (ret == GNUNET_SYSERR) itable (plugin); return GNUNET_SYSERR; } return size + OVERHEAD; } static int return_ok (void *cls, unsigned int num_values, MYSQL_BIND * values) { return GNUNET_OK; } /** * Iterate over the results for a particular key * in the datastore. * * @param cls closure (our "struct Plugin") * @param key * @param type entries of which type are relevant? * @param iter maybe NULL (to just count) * @param iter_cls closure for iter * @return the number of results found */ static unsigned int mysql_plugin_get (void *cls, const GNUNET_HashCode * key, enum GNUNET_BLOCK_Type type, GNUNET_DATACACHE_Iterator iter, void *iter_cls) { struct Plugin *plugin = cls; MYSQL_BIND rbind[3]; unsigned long h_length; unsigned long v_length; unsigned long long v_expire; struct GNUNET_TIME_Absolute now; struct GNUNET_TIME_Absolute expire; unsigned int cnt; unsigned long long total; unsigned long long v_now; unsigned int off; unsigned int v_type; int ret; char buffer[GNUNET_SERVER_MAX_MESSAGE_SIZE]; now = GNUNET_TIME_absolute_get (); h_length = sizeof (GNUNET_HashCode); v_length = sizeof (buffer); total = -1; memset (rbind, 0, sizeof (rbind)); rbind[0].buffer_type = MYSQL_TYPE_LONGLONG; rbind[0].buffer = &total; rbind[0].is_unsigned = GNUNET_YES; v_type = type; v_now = (unsigned long long) now.abs_value; if ((GNUNET_OK != (ret = GNUNET_MYSQL_statement_run_prepared_select (plugin->mc, plugin->count_value, 1, rbind, return_ok, NULL, MYSQL_TYPE_BLOB, key, sizeof (GNUNET_HashCode), &h_length, MYSQL_TYPE_LONG, &v_type, GNUNET_YES, MYSQL_TYPE_LONGLONG, &v_now, GNUNET_YES, -1))) || (-1 == total)) { if (ret == GNUNET_SYSERR) itable (plugin); return GNUNET_SYSERR; } if ((iter == NULL) || (total == 0)) return (int) total; off = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, total); cnt = 0; while (cnt < total) { memset (rbind, 0, sizeof (rbind)); rbind[0].buffer_type = MYSQL_TYPE_BLOB; rbind[0].buffer_length = sizeof (buffer); rbind[0].length = &v_length; rbind[0].buffer = buffer; rbind[1].buffer_type = MYSQL_TYPE_LONGLONG; rbind[1].is_unsigned = 1; rbind[1].buffer = &v_expire; off = (off + 1) % total; if (GNUNET_OK != (ret = GNUNET_MYSQL_statement_run_prepared_select (plugin->mc, plugin->select_value, 2, rbind, return_ok, NULL, MYSQL_TYPE_BLOB, key, sizeof (GNUNET_HashCode), &h_length, MYSQL_TYPE_LONG, &v_type, GNUNET_YES, MYSQL_TYPE_LONGLONG, &v_now, GNUNET_YES, MYSQL_TYPE_LONG, &off, GNUNET_YES, -1))) { if (ret == GNUNET_SYSERR) itable (plugin); return GNUNET_SYSERR; } cnt++; expire.abs_value = v_expire; if (GNUNET_OK != iter (iter_cls, expire, key, v_length, buffer, type)) break; } return cnt; } /** * Delete the entry with the lowest expiration value * from the datacache right now. * * @param cls closure (our "struct Plugin") * @return GNUNET_OK on success, GNUNET_SYSERR on error */ static int mysql_plugin_del (void *cls) { struct Plugin *plugin = cls; MYSQL_BIND rbind[5]; unsigned int v_type; GNUNET_HashCode v_key; GNUNET_HashCode vhash; unsigned long k_length; unsigned long h_length; unsigned long v_length; int ret; char buffer[GNUNET_SERVER_MAX_MESSAGE_SIZE]; k_length = sizeof (GNUNET_HashCode); h_length = sizeof (GNUNET_HashCode); v_length = sizeof (buffer); memset (rbind, 0, sizeof (rbind)); rbind[0].buffer_type = MYSQL_TYPE_BLOB; rbind[0].buffer_length = sizeof (GNUNET_HashCode); rbind[0].length = &k_length; rbind[0].buffer = &v_key; rbind[1].buffer_type = MYSQL_TYPE_BLOB; rbind[1].buffer_length = sizeof (GNUNET_HashCode); rbind[1].length = &h_length; rbind[1].buffer = &vhash; rbind[2].buffer_type = MYSQL_TYPE_LONG; rbind[2].is_unsigned = 1; rbind[2].buffer = &v_type; rbind[3].buffer_type = MYSQL_TYPE_BLOB; rbind[3].buffer_length = sizeof (buffer); rbind[3].length = &v_length; rbind[3].buffer = buffer; if ((GNUNET_OK != (ret = GNUNET_MYSQL_statement_run_prepared_select (plugin->mc, plugin->select_old_value, 4, rbind, return_ok, NULL, -1))) || (GNUNET_OK != (ret = GNUNET_MYSQL_statement_run_prepared (plugin->mc, plugin->delete_value, NULL, MYSQL_TYPE_BLOB, &v_key, sizeof (GNUNET_HashCode), &k_length, MYSQL_TYPE_BLOB, &vhash, sizeof (GNUNET_HashCode), &h_length, MYSQL_TYPE_LONG, &v_type, GNUNET_YES, MYSQL_TYPE_BLOB, buffer, (unsigned long) sizeof (buffer), &v_length, -1)))) { if (ret == GNUNET_SYSERR) itable (plugin); return GNUNET_SYSERR; } plugin->env->delete_notify (plugin->env->cls, &v_key, v_length + OVERHEAD); return GNUNET_OK; } /** * Entry point for the plugin. * * @param cls closure (the "struct GNUNET_DATACACHE_PluginEnvironmnet") * @return the plugin's closure (our "struct Plugin") */ void * libgnunet_plugin_datacache_mysql_init (void *cls) { struct GNUNET_DATACACHE_PluginEnvironment *env = cls; struct GNUNET_DATACACHE_PluginFunctions *api; struct Plugin *plugin; plugin = GNUNET_malloc (sizeof (struct Plugin)); plugin->env = env; plugin->mc = GNUNET_MYSQL_context_create (env->cfg, "datacache-mysql"); if ( (NULL == plugin->mc) || (GNUNET_OK != itable (plugin)) ) { if (NULL != plugin->mc) GNUNET_MYSQL_context_destroy (plugin->mc); GNUNET_free (plugin); return NULL; } api = GNUNET_malloc (sizeof (struct GNUNET_DATACACHE_PluginFunctions)); api->cls = plugin; api->get = &mysql_plugin_get; api->put = &mysql_plugin_put; api->del = &mysql_plugin_del; GNUNET_log_from (GNUNET_ERROR_TYPE_INFO, "mysql", _("MySQL datacache running\n")); return api; } /** * Exit point from the plugin. * * @param cls closure (our "struct Plugin") * @return NULL */ void * libgnunet_plugin_datacache_mysql_done (void *cls) { struct GNUNET_DATACACHE_PluginFunctions *api = cls; struct Plugin *plugin = api->cls; GNUNET_MYSQL_context_destroy (plugin->mc); GNUNET_free (plugin); GNUNET_free (api); return NULL; } /* end of plugin_datacache_mysql.c */