/*
* This file is part of GNUnet
* Copyright (C) 2009-2013 GNUnet e.V.
*
* GNUnet is free software: you can redistribute it and/or modify it
* under the terms of the GNU Affero General Public License as published
* by the Free Software Foundation, either version 3 of the License,
* 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
* Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see .
*/
/**
* @file namecache/plugin_namecache_sqlite.c
* @brief sqlite-based namecache backend
* @author Christian Grothoff
*/
#include "platform.h"
#include "gnunet_sq_lib.h"
#include "gnunet_namecache_plugin.h"
#include "gnunet_namecache_service.h"
#include "gnunet_gnsrecord_lib.h"
#include "namecache.h"
#include
/**
* After how many ms "busy" should a DB operation fail for good? A
* low value makes sure that we are more responsive to requests
* (especially PUTs). A high value guarantees a higher success rate
* (SELECTs in iterate can take several seconds despite LIMIT=1).
*
* The default value of 1s should ensure that users do not experience
* huge latencies while at the same time allowing operations to
* succeed with reasonable probability.
*/
#define BUSY_TIMEOUT_MS 1000
/**
* 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_SQLITE(db, level, cmd) do { GNUNET_log_from (level, "namecache-sqlite", _("`%s' failed at %s:%d with error: %s\n"), cmd, __FILE__, __LINE__, sqlite3_errmsg(db->dbh)); } while(0)
#define LOG(kind,...) GNUNET_log_from (kind, "namecache-sqlite", __VA_ARGS__)
/**
* Context for all functions in this plugin.
*/
struct Plugin
{
const struct GNUNET_CONFIGURATION_Handle *cfg;
/**
* Database filename.
*/
char *fn;
/**
* Native SQLite database handle.
*/
sqlite3 *dbh;
/**
* Precompiled SQL for caching a block
*/
sqlite3_stmt *cache_block;
/**
* Precompiled SQL for deleting an older block
*/
sqlite3_stmt *delete_block;
/**
* Precompiled SQL for looking up a block
*/
sqlite3_stmt *lookup_block;
/**
* Precompiled SQL for removing expired blocks
*/
sqlite3_stmt *expire_blocks;
};
/**
* @brief Prepare a SQL statement
*
* @param dbh handle to the database
* @param zSql SQL statement, UTF-8 encoded
* @param ppStmt set to the prepared statement
* @return 0 on success
*/
static int
sq_prepare (sqlite3 *dbh,
const char *zSql,
sqlite3_stmt **ppStmt)
{
char *dummy;
int result;
result = sqlite3_prepare_v2 (dbh,
zSql,
strlen (zSql),
ppStmt,
(const char **) &dummy);
LOG (GNUNET_ERROR_TYPE_DEBUG,
"Prepared `%s' / %p: %d\n",
zSql,
*ppStmt,
result);
return result;
}
/**
* Create our database indices.
*
* @param dbh handle to the database
*/
static void
create_indices (sqlite3 * dbh)
{
/* create indices */
if ( (SQLITE_OK !=
sqlite3_exec (dbh,
"CREATE INDEX IF NOT EXISTS ir_query_hash ON ns096blocks (query,expiration_time)",
NULL, NULL, NULL)) ||
(SQLITE_OK !=
sqlite3_exec (dbh,
"CREATE INDEX IF NOT EXISTS ir_block_expiration ON ns096blocks (expiration_time)",
NULL, NULL, NULL)) )
LOG (GNUNET_ERROR_TYPE_ERROR,
"Failed to create indices: %s\n",
sqlite3_errmsg (dbh));
}
#if 0
#define CHECK(a) GNUNET_break(a)
#define ENULL NULL
#else
#define ENULL &e
#define ENULL_DEFINED 1
#define CHECK(a) if (! (a)) { GNUNET_log(GNUNET_ERROR_TYPE_ERROR, "%s\n", e); sqlite3_free(e); }
#endif
/**
* Initialize the database connections and associated
* data structures (create tables and indices
* as needed as well).
*
* @param plugin the plugin context (state for this module)
* @return #GNUNET_OK on success
*/
static int
database_setup (struct Plugin *plugin)
{
sqlite3_stmt *stmt;
char *afsdir;
#if ENULL_DEFINED
char *e;
#endif
if (GNUNET_OK !=
GNUNET_CONFIGURATION_get_value_filename (plugin->cfg,
"namecache-sqlite",
"FILENAME",
&afsdir))
{
GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR,
"namecache-sqlite",
"FILENAME");
return GNUNET_SYSERR;
}
if (GNUNET_OK !=
GNUNET_DISK_file_test (afsdir))
{
if (GNUNET_OK !=
GNUNET_DISK_directory_create_for_file (afsdir))
{
GNUNET_break (0);
GNUNET_free (afsdir);
return GNUNET_SYSERR;
}
}
/* afsdir should be UTF-8-encoded. If it isn't, it's a bug */
plugin->fn = afsdir;
/* Open database and precompile statements */
if (SQLITE_OK !=
sqlite3_open (plugin->fn, &plugin->dbh))
{
LOG (GNUNET_ERROR_TYPE_ERROR,
_("Unable to initialize SQLite: %s.\n"),
sqlite3_errmsg (plugin->dbh));
return GNUNET_SYSERR;
}
CHECK (SQLITE_OK ==
sqlite3_exec (plugin->dbh,
"PRAGMA temp_store=MEMORY",
NULL, NULL,
ENULL));
CHECK (SQLITE_OK ==
sqlite3_exec (plugin->dbh,
"PRAGMA synchronous=NORMAL",
NULL, NULL,
ENULL));
CHECK (SQLITE_OK ==
sqlite3_exec (plugin->dbh,
"PRAGMA legacy_file_format=OFF",
NULL, NULL,
ENULL));
CHECK (SQLITE_OK ==
sqlite3_exec (plugin->dbh,
"PRAGMA auto_vacuum=INCREMENTAL",
NULL, NULL,
ENULL));
CHECK (SQLITE_OK ==
sqlite3_exec (plugin->dbh,
"PRAGMA encoding=\"UTF-8\"",
NULL, NULL,
ENULL));
CHECK (SQLITE_OK ==
sqlite3_exec (plugin->dbh,
"PRAGMA locking_mode=EXCLUSIVE",
NULL, NULL,
ENULL));
CHECK (SQLITE_OK ==
sqlite3_exec (plugin->dbh,
"PRAGMA page_size=4092",
NULL, NULL,
ENULL));
CHECK (SQLITE_OK ==
sqlite3_busy_timeout (plugin->dbh,
BUSY_TIMEOUT_MS));
/* Create tables */
CHECK (SQLITE_OK ==
sq_prepare (plugin->dbh,
"SELECT 1 FROM sqlite_master WHERE tbl_name = 'ns096blocks'",
&stmt));
if ( (sqlite3_step (stmt) == SQLITE_DONE) &&
(SQLITE_OK !=
sqlite3_exec (plugin->dbh,
"CREATE TABLE ns096blocks ("
" query BLOB NOT NULL,"
" block BLOB NOT NULL,"
" expiration_time INT8 NOT NULL"
")",
NULL, NULL, NULL)) )
{
LOG_SQLITE (plugin,
GNUNET_ERROR_TYPE_ERROR,
"sqlite3_exec");
sqlite3_finalize (stmt);
return GNUNET_SYSERR;
}
sqlite3_finalize (stmt);
create_indices (plugin->dbh);
if ( (SQLITE_OK !=
sq_prepare (plugin->dbh,
"INSERT INTO ns096blocks (query,block,expiration_time) VALUES (?, ?, ?)",
&plugin->cache_block)) ||
(SQLITE_OK !=
sq_prepare (plugin->dbh,
"DELETE FROM ns096blocks WHERE expiration_timeexpire_blocks)) ||
(SQLITE_OK !=
sq_prepare (plugin->dbh,
"DELETE FROM ns096blocks WHERE query=? AND expiration_time<=?",
&plugin->delete_block)) ||
(SQLITE_OK !=
sq_prepare (plugin->dbh,
"SELECT block FROM ns096blocks WHERE query=? "
"ORDER BY expiration_time DESC LIMIT 1",
&plugin->lookup_block) )
)
{
LOG_SQLITE (plugin,
GNUNET_ERROR_TYPE_ERROR,
"precompiling");
return GNUNET_SYSERR;
}
return GNUNET_OK;
}
/**
* Shutdown database connection and associate data
* structures.
* @param plugin the plugin context (state for this module)
*/
static void
database_shutdown (struct Plugin *plugin)
{
int result;
sqlite3_stmt *stmt;
if (NULL != plugin->cache_block)
sqlite3_finalize (plugin->cache_block);
if (NULL != plugin->lookup_block)
sqlite3_finalize (plugin->lookup_block);
if (NULL != plugin->expire_blocks)
sqlite3_finalize (plugin->expire_blocks);
if (NULL != plugin->delete_block)
sqlite3_finalize (plugin->delete_block);
result = sqlite3_close (plugin->dbh);
if (result == SQLITE_BUSY)
{
LOG (GNUNET_ERROR_TYPE_WARNING,
_("Tried to close sqlite without finalizing all prepared statements.\n"));
stmt = sqlite3_next_stmt (plugin->dbh, NULL);
while (stmt != NULL)
{
GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "sqlite",
"Closing statement %p\n", stmt);
result = sqlite3_finalize (stmt);
if (result != SQLITE_OK)
GNUNET_log_from (GNUNET_ERROR_TYPE_WARNING, "sqlite",
"Failed to close statement %p: %d\n", stmt, result);
stmt = sqlite3_next_stmt (plugin->dbh, NULL);
}
result = sqlite3_close (plugin->dbh);
}
if (SQLITE_OK != result)
LOG_SQLITE (plugin, GNUNET_ERROR_TYPE_ERROR, "sqlite3_close");
GNUNET_free_non_null (plugin->fn);
}
/**
* Removes any expired block.
*
* @param plugin the plugin
*/
static void
namecache_sqlite_expire_blocks (struct Plugin *plugin)
{
struct GNUNET_TIME_Absolute now;
struct GNUNET_SQ_QueryParam params[] = {
GNUNET_SQ_query_param_absolute_time (&now),
GNUNET_SQ_query_param_end
};
int n;
now = GNUNET_TIME_absolute_get ();
if (GNUNET_OK !=
GNUNET_SQ_bind (plugin->expire_blocks,
params))
{
LOG_SQLITE (plugin, GNUNET_ERROR_TYPE_ERROR | GNUNET_ERROR_TYPE_BULK,
"sqlite3_bind_XXXX");
GNUNET_SQ_reset (plugin->dbh,
plugin->expire_blocks);
return;
}
n = sqlite3_step (plugin->expire_blocks);
GNUNET_SQ_reset (plugin->dbh,
plugin->expire_blocks);
switch (n)
{
case SQLITE_DONE:
GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
"sqlite",
"Records expired\n");
return;
case SQLITE_BUSY:
LOG_SQLITE (plugin,
GNUNET_ERROR_TYPE_WARNING | GNUNET_ERROR_TYPE_BULK,
"sqlite3_step");
return;
default:
LOG_SQLITE (plugin,
GNUNET_ERROR_TYPE_ERROR | GNUNET_ERROR_TYPE_BULK,
"sqlite3_step");
return;
}
}
/**
* Cache a block in the datastore.
*
* @param cls closure (internal context for the plugin)
* @param block block to cache
* @return #GNUNET_OK on success, else #GNUNET_SYSERR
*/
static int
namecache_sqlite_cache_block (void *cls,
const struct GNUNET_GNSRECORD_Block *block)
{
struct Plugin *plugin = cls;
struct GNUNET_HashCode query;
struct GNUNET_TIME_Absolute expiration;
size_t block_size = ntohl (block->purpose.size) +
sizeof (struct GNUNET_CRYPTO_EcdsaPublicKey) +
sizeof (struct GNUNET_CRYPTO_EcdsaSignature);
struct GNUNET_SQ_QueryParam del_params[] = {
GNUNET_SQ_query_param_auto_from_type (&query),
GNUNET_SQ_query_param_absolute_time (&expiration),
GNUNET_SQ_query_param_end
};
struct GNUNET_SQ_QueryParam ins_params[] = {
GNUNET_SQ_query_param_auto_from_type (&query),
GNUNET_SQ_query_param_fixed_size (block,
block_size),
GNUNET_SQ_query_param_absolute_time (&expiration),
GNUNET_SQ_query_param_end
};
int n;
namecache_sqlite_expire_blocks (plugin);
GNUNET_CRYPTO_hash (&block->derived_key,
sizeof (struct GNUNET_CRYPTO_EcdsaPublicKey),
&query);
expiration = GNUNET_TIME_absolute_ntoh (block->expiration_time);
GNUNET_log (GNUNET_ERROR_TYPE_INFO,
"Caching new version of block %s (expires %s)\n",
GNUNET_h2s (&query),
GNUNET_STRINGS_absolute_time_to_string (expiration));
if (block_size > 64 * 65536)
{
GNUNET_break (0);
return GNUNET_SYSERR;
}
/* delete old version of the block */
if (GNUNET_OK !=
GNUNET_SQ_bind (plugin->delete_block,
del_params))
{
LOG_SQLITE (plugin, GNUNET_ERROR_TYPE_ERROR | GNUNET_ERROR_TYPE_BULK,
"sqlite3_bind_XXXX");
GNUNET_SQ_reset (plugin->dbh,
plugin->delete_block);
return GNUNET_SYSERR;
}
n = sqlite3_step (plugin->delete_block);
switch (n)
{
case SQLITE_DONE:
GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
"sqlite",
"Old block deleted\n");
break;
case SQLITE_BUSY:
LOG_SQLITE (plugin,
GNUNET_ERROR_TYPE_WARNING | GNUNET_ERROR_TYPE_BULK,
"sqlite3_step");
break;
default:
LOG_SQLITE (plugin,
GNUNET_ERROR_TYPE_ERROR | GNUNET_ERROR_TYPE_BULK,
"sqlite3_step");
break;
}
GNUNET_SQ_reset (plugin->dbh,
plugin->delete_block);
/* insert new version of the block */
if (GNUNET_OK !=
GNUNET_SQ_bind (plugin->cache_block,
ins_params))
{
LOG_SQLITE (plugin,
GNUNET_ERROR_TYPE_ERROR | GNUNET_ERROR_TYPE_BULK,
"sqlite3_bind_XXXX");
GNUNET_SQ_reset (plugin->dbh,
plugin->cache_block);
return GNUNET_SYSERR;
}
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"Caching block under derived key `%s'\n",
GNUNET_h2s_full (&query));
n = sqlite3_step (plugin->cache_block);
GNUNET_SQ_reset (plugin->dbh,
plugin->cache_block);
switch (n)
{
case SQLITE_DONE:
LOG (GNUNET_ERROR_TYPE_DEBUG,
"Record stored\n");
return GNUNET_OK;
case SQLITE_BUSY:
LOG_SQLITE (plugin,
GNUNET_ERROR_TYPE_WARNING | GNUNET_ERROR_TYPE_BULK,
"sqlite3_step");
return GNUNET_NO;
default:
LOG_SQLITE (plugin,
GNUNET_ERROR_TYPE_ERROR | GNUNET_ERROR_TYPE_BULK,
"sqlite3_step");
return GNUNET_SYSERR;
}
}
/**
* Get the block for a particular zone and label in the
* datastore. Will return at most one result to the iterator.
*
* @param cls closure (internal context for the plugin)
* @param query hash of public key derived from the zone and the label
* @param iter function to call with the result
* @param iter_cls closure for @a iter
* @return #GNUNET_OK on success, #GNUNET_NO if there were no results, #GNUNET_SYSERR on error
*/
static int
namecache_sqlite_lookup_block (void *cls,
const struct GNUNET_HashCode *query,
GNUNET_NAMECACHE_BlockCallback iter,
void *iter_cls)
{
struct Plugin *plugin = cls;
int ret;
int sret;
size_t block_size;
const struct GNUNET_GNSRECORD_Block *block;
struct GNUNET_SQ_QueryParam params[] = {
GNUNET_SQ_query_param_auto_from_type (query),
GNUNET_SQ_query_param_end
};
struct GNUNET_SQ_ResultSpec rs[] = {
GNUNET_SQ_result_spec_variable_size ((void **) &block,
&block_size),
GNUNET_SQ_result_spec_end
};
if (GNUNET_OK !=
GNUNET_SQ_bind (plugin->lookup_block,
params))
{
LOG_SQLITE (plugin,
GNUNET_ERROR_TYPE_ERROR | GNUNET_ERROR_TYPE_BULK,
"sqlite3_bind_XXXX");
GNUNET_SQ_reset (plugin->dbh,
plugin->lookup_block);
return GNUNET_SYSERR;
}
ret = GNUNET_NO;
if (SQLITE_ROW ==
(sret = sqlite3_step (plugin->lookup_block)))
{
if (GNUNET_OK !=
GNUNET_SQ_extract_result (plugin->lookup_block,
rs))
{
GNUNET_break (0);
ret = GNUNET_SYSERR;
}
else if ( (block_size < sizeof (struct GNUNET_GNSRECORD_Block)) ||
(ntohl (block->purpose.size) +
sizeof (struct GNUNET_CRYPTO_EcdsaPublicKey) +
sizeof (struct GNUNET_CRYPTO_EcdsaSignature) != block_size) )
{
GNUNET_break (0);
GNUNET_SQ_cleanup_result (rs);
ret = GNUNET_SYSERR;
}
else
{
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"Found block under derived key `%s'\n",
GNUNET_h2s_full (query));
iter (iter_cls,
block);
GNUNET_SQ_cleanup_result (rs);
ret = GNUNET_YES;
}
}
else
{
if (SQLITE_DONE != sret)
{
LOG_SQLITE (plugin,
GNUNET_ERROR_TYPE_ERROR,
"sqlite_step");
ret = GNUNET_SYSERR;
}
else
{
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"No block found under derived key `%s'\n",
GNUNET_h2s_full (query));
}
}
GNUNET_SQ_reset (plugin->dbh,
plugin->lookup_block);
return ret;
}
/**
* Entry point for the plugin.
*
* @param cls the "struct GNUNET_NAMECACHE_PluginEnvironment*"
* @return NULL on error, otherwise the plugin context
*/
void *
libgnunet_plugin_namecache_sqlite_init (void *cls)
{
static struct Plugin plugin;
const struct GNUNET_CONFIGURATION_Handle *cfg = cls;
struct GNUNET_NAMECACHE_PluginFunctions *api;
if (NULL != plugin.cfg)
return NULL; /* can only initialize once! */
memset (&plugin, 0, sizeof (struct Plugin));
plugin.cfg = cfg;
if (GNUNET_OK != database_setup (&plugin))
{
database_shutdown (&plugin);
return NULL;
}
api = GNUNET_new (struct GNUNET_NAMECACHE_PluginFunctions);
api->cls = &plugin;
api->cache_block = &namecache_sqlite_cache_block;
api->lookup_block = &namecache_sqlite_lookup_block;
LOG (GNUNET_ERROR_TYPE_INFO,
_("Sqlite database running\n"));
return api;
}
/**
* Exit point from the plugin.
*
* @param cls the plugin context (as returned by "init")
* @return always NULL
*/
void *
libgnunet_plugin_namecache_sqlite_done (void *cls)
{
struct GNUNET_NAMECACHE_PluginFunctions *api = cls;
struct Plugin *plugin = api->cls;
database_shutdown (plugin);
plugin->cfg = NULL;
GNUNET_free (api);
LOG (GNUNET_ERROR_TYPE_DEBUG,
"sqlite plugin is finished\n");
return NULL;
}
/* end of plugin_namecache_sqlite.c */