<?php
/*
** Zabbix
** Copyright (C) 2001-2023 Zabbix SIA
**
** This program 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 2 of the License, or
** (at your option) any later version.
**
** This program is distributed in the hope that it will be useful,
** but WITHOUT ANY WARRANTY; without even the implied warranty of
** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
** GNU General Public License for more details.
**
** You should have received a copy of the GNU General Public License
** along with this program; if not, write to the Free Software
** Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
**/
/**
* Database backend class for PostgreSQL.
*/
class PostgresqlDbBackend extends DbBackend {
/**
* Database name.
*
* @var string
*/
protected $dbname = '';
/**
* DB schema.
*
* @var string
*/
protected $schema = '';
/**
* User name.
*
* @var string
*/
protected $user = '';
/**
* Check if 'dbversion' table exists.
*
* @return bool
*/
protected function checkDbVersionTable() {
$table_exists = DBfetch(DBselect(
'SELECT 1 FROM information_schema.tables'.
' WHERE table_catalog='.zbx_dbstr($this->dbname).
' AND table_schema='.zbx_dbstr($this->schema).
' AND table_name='.zbx_dbstr('dbversion')
));
if (!$table_exists) {
$this->setError(_s('Unable to determine current Zabbix database version: %1$s.',
_s('the table "%1$s" was not found', 'dbversion')
));
return false;
}
return true;
}
/**
* Check database and table fields encoding.
*
* @return bool
*/
public function checkEncoding() {
global $DB;
return $this->checkDatabaseEncoding($DB) && $this->checkTablesEncoding($DB);
}
/**
* Check database schema encoding. On error will set warning message.
*
* @param array $DB Array of database settings, same as global $DB.
*
* @return bool
*/
protected function checkDatabaseEncoding(array $DB) {
$row = DBfetch(DBselect('SELECT pg_encoding_to_char(encoding) db_charset FROM pg_database'.
' WHERE datname='.zbx_dbstr($DB['DATABASE'])
));
if ($row && $row['db_charset'] != ZBX_DB_POSTGRESQL_ALLOWED_CHARSET) {
$this->setWarning(_s('Incorrect default charset for Zabbix database: %1$s.',
_s('"%1$s" instead "%2$s"', $row['db_charset'], ZBX_DB_POSTGRESQL_ALLOWED_CHARSET)
));
return false;
}
return true;
}
/**
* Check tables schema encoding. On error will set warning message.
*
* @param array $DB Array of database settings, same as global $DB.
*
* @return bool
*/
protected function checkTablesEncoding(array $DB) {
$schema = $DB['SCHEMA'] ? $DB['SCHEMA'] : 'public';
$row = DBfetch(DBselect('SELECT oid FROM pg_namespace WHERE nspname='.zbx_dbstr($schema)));
/**
* Getting all fields in all Zabbix tables to check for collation.
* If collation is not default (its mean collation is the same that was during db creation),
* than we consider it as error.
*/
$tables = DBfetchColumn(DBSelect('SELECT c.relname AS table_name FROM pg_attribute AS a'.
' LEFT JOIN pg_class AS c ON c.relfilenode=a.attrelid'.
' LEFT JOIN pg_collation AS l ON l.oid=a.attcollation'.
' WHERE '.dbConditionInt('atttypid', [25, 1043]).
' AND '.dbConditionInt('c.relnamespace', [$row['oid']]).
' AND c.relam=0 AND '.dbConditionString('c.relname', array_keys(DB::getSchema())).
' AND l.collname!='.zbx_dbstr('default')
), 'table_name');
if ($tables) {
$tables = array_unique($tables);
$this->setWarning(_n('Unsupported charset or collation for table: %1$s.',
'Unsupported charset or collation for tables: %1$s.',
implode(', ', $tables), implode(', ', $tables), count($tables)
));
return false;
}
return true;
}
/**
* Check is current connection contain requested cipher list.
*
* @return bool
*/
public function isConnectionSecure() {
$row = DBfetch(DBselect('SHOW server_version'));
$is_secure = false;
if (version_compare($row['server_version'], '9.5', '<')) {
$row = DBfetch(DBselect('SHOW ssl'));
$is_secure = ($row && $row['ssl'] === 'on');
}
else {
$is_secure = (bool) DBfetch(DBselect('SELECT datname,usename,ssl,client_addr,cipher FROM pg_stat_ssl'.
' JOIN pg_stat_activity ON pg_stat_ssl.pid=pg_stat_activity.pid'.
' AND pg_stat_activity.usename='.zbx_dbstr($this->user)));
}
if (!$is_secure) {
$this->setError('Error connecting to database. Connection is not secure.');
}
return $is_secure;
}
/**
* Create connection to database server.
*
* @param string $host Host name.
* @param string $port Port.
* @param string $user User name.
* @param string $password Password.
* @param string $dbname Database name.
* @param string $schema DB schema.
*
* @param
* @return resource|null
*/
public function connect($host, $port, $user, $password, $dbname, $schema) {
$this->user = $user;
$this->dbname = $dbname;
$this->schema = ($schema) ? $schema : 'public';
$params = compact(['host', 'port', 'user', 'password', 'dbname']);
if ($this->tls_encryption && (bool) $this->tls_ca_file) {
$params += [
'sslmode' => $this->tls_verify_host ? 'verify-full' : 'verify-ca',
'sslkey' => $this->tls_key_file,
'sslcert' => $this->tls_cert_file,
'sslrootcert' => $this->tls_ca_file
];
}
$conn_string = '';
foreach ($params as $key => $param) {
$conn_string .= ((bool) $param) ? $key.'=\''.pg_connect_escape($param).'\' ' : '';
}
$resource = @pg_connect($conn_string);
if (!$resource) {
$this->setError('Error connecting to database.');
return null;
}
return $resource;
}
/**
* Initialize database connection.
*
* @return bool
*/
public function init() {
global $DB;
$schema_set = DBexecute('SET search_path='.zbx_dbstr($this->schema));
if (!$schema_set) {
$this->setError(pg_last_error($DB['DB']));
return false;
}
$pgsql_version = pg_parameter_status($DB['DB'], 'server_version');
if ($pgsql_version !== false && (int) $pgsql_version >= 9) {
// change the output format for values of type bytea from hex (the default) to escape
DBexecute('SET bytea_output=escape');
}
return true;
}
/**
* Check if tables have compressed data.
*
* @static
*
* @param array $tables Tables list.
*
* @return bool
*/
public static function isCompressed(array $tables): bool {
if (CHousekeepingHelper::get(CHousekeepingHelper::DB_EXTENSION) != ZBX_DB_EXTENSION_TIMESCALEDB) {
return false;
}
$timescale_v1 = DBfetch(DBselect(
'SELECT NULL FROM pg_catalog.pg_class c'.
' JOIN pg_catalog.pg_namespace n'.
' ON n.oid=c.relnamespace'.
' WHERE n.nspname='.zbx_dbstr('timescaledb_information').
' AND c.relname='.zbx_dbstr('compressed_hypertable_stats')
));
if ($timescale_v1) {
$result = DBfetch(DBselect('SELECT coalesce(sum(number_compressed_chunks),0) chunks'.
' FROM timescaledb_information.compressed_hypertable_stats'.
' WHERE number_compressed_chunks != 0 AND '.dbConditionString('hypertable_name::text', $tables)
));
return (bool) $result['chunks'];
}
$query = implode(' UNION ', array_map(function ($table) {
return 'SELECT number_compressed_chunks chunks'.
' FROM hypertable_compression_stats('.zbx_dbstr($table).')'.
' WHERE number_compressed_chunks != 0';
}, $tables));
$result = DBfetch(DBselect($query));
return (bool) $result['chunks'];
}
}