<?php

/*

 * Enano - an open-source CMS capable of wiki functions, Drupal-like sidebar blocks, and everything in between

 * Copyright (C) 2006-2009 Dan Fuhry

 *

 * This program is Free Software; you can redistribute 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 details.

 */

function db_error_handler($errno, $errstr, $errfile = false, $errline = false, $errcontext = Array() )

{

  if ( !defined('ENANO_DEBUG') )

    return;

  $e = error_reporting(0);

  error_reporting($e);

  if ( $e < $errno )

    return;

  $errtype = 'Notice';

  switch ( $errno )

  {

    case E_ERROR: case E_USER_ERROR: case E_CORE_ERROR: case E_COMPILE_ERROR: $errtype = 'Error'; break;

    case E_WARNING: case E_USER_WARNING: case E_CORE_WARNING: case E_COMPILE_WARNING: $errtype = 'Warning'; break;

  }

  $debug = debug_backtrace();

  if ( !isset($debug[0]['file']) )

    return false;

  $debug = $debug[0]['file'] . ', line ' . $debug[0]['line'];

  echo "<b>$errtype:</b> $errstr<br />Error source:<pre>$debug</pre>";

}

global $db_sql_parse_time;

$db_sql_parse_time = 0;

class mysql {

  var $num_queries, $query_backtrace, $query_times, $query_sources, $latest_result, $latest_query, $_conn, $sql_stack_fields, $sql_stack_values, $debug;

  var $row = array();

	var $rowset = array();

  var $errhandler;

  var $dbms_name = 'MySQL';

  /**

   * Get a flat textual list of queries that have been made.

   */

  function sql_backtrace()

  {

    return implode("\n-------------------------------------------------------------------\n", $this->query_backtrace);

  }

  /**

   * Connect to the database, but only if a connection isn't already up.

   */

  function ensure_connection()

  {

    if(!$this->_conn)

    {

      $this->connect();

    }

  }

  /**

   * Exit Enano, dumping out a friendly error message indicating a database error on the way out.

   * @param string Description or location of error; defaults to none

   */

  function _die($t = '')

  {

    if ( defined('ENANO_HEADERS_SENT') )

      ob_clean();

    $internal_text = $this->get_error($t);

    if ( defined('ENANO_CONFIG_FETCHED') )

      // config is in, we can show a slightly nicer looking error page

      die_semicritical('Database error', $internal_text);

    else

      // no config, display using no-DB template engine

      grinding_halt('Database error', $internal_text);

    exit;

  }

  /**

   * Get the internal text used for a database error message.

   * @param string Description or location of error; defaults to none

   */

  function get_error($t = '')

  {

    @header('HTTP/1.1 500 Internal Server Error');

    $bt = $this->latest_query;

    $e = htmlspecialchars($this->sql_error());

    if ( empty($e) )

      $e = '<none>';

    global $email;

    // As long as the admin's e-mail is accessible, display it.

    $email_info = ( defined('ENANO_CONFIG_FETCHED') && is_object($email) )

                    ? ', at <' . $email->jscode() . $email->encryptEmail(getConfig('contact_email')) . '>'

                    : '';

    $internal_text = "<h3>The site was unable to finish serving your request.</h3>

                      <p>We apologize for the inconveience, but an error occurred in the Enano database layer. Please report the full text of this page to the administrator of this site{$email_info}.</p>

                      <p>Description or location of error: $t<br />

                      Error returned by $this->dbms_name extension: $e</p>

                      <p>Most recent SQL query:</p>

                      <pre>$bt</pre>";

    return $internal_text;

  }

  /**

   * Exit Enano and output a JSON format datbase error.

   * @param string Description or location of error; defaults to none

   */

  function die_json($loc = false)

  {

    $e = str_replace("\n", "\\n", addslashes(htmlspecialchars($this->sql_error())));

    $q = str_replace("\n", "\\n", addslashes($this->latest_query));

    $loc = ( $loc ) ? addslashes("\n\nDescription or location of error: $loc") : "";

    $loc .= "\n\nPlease report the full text of this error to the administrator of the site. If you believe that this is a bug with the software, please contact support@enanocms.org.";

    $loc = str_replace("\n", "\\n", $loc);

    $t = "{\"mode\":\"error\",\"error\":\"An error occurred during database query.\\nQuery was:\\n  $q\\n\\nError returned by {$this->dbms_name}: $e$loc\"}";

    die($t);

  }

  /**

   * Connect to the database.

   * @param bool If true, enables all other parameters. Defaults to false, which emans that you can call this function with no arguments and it will fetch information from the config file.

   * @param string Database server hostname

   * @param string Database server username

   * @param string Database server password

   * @param string Name of the database

   * @param int Optional port number to connect over

   */

  function connect($manual_credentials = false, $dbhost = false, $dbuser = false, $dbpasswd = false, $dbname = false, $dbport = false)

  {

    if ( !defined('ENANO_SQL_CONSTANTS') )

    {

      define('ENANO_SQL_CONSTANTS', '');

      define('ENANO_DBLAYER', 'MYSQL');

      define('ENANO_SQLFUNC_LOWERCASE', 'lcase');

      define('ENANO_SQL_MULTISTRING_PRFIX', '');

      define('ENANO_SQL_BOOLEAN_TRUE', 'true');

      define('ENANO_SQL_BOOLEAN_FALSE', 'false');

    }

    if ( !$manual_credentials )

    {

      if ( defined('IN_ENANO_INSTALL') && !defined('IN_ENANO_UPGRADE') )

      {

        @include(ENANO_ROOT.'/config.new.php');

      }

      else

      {

        @include(ENANO_ROOT.'/config.php');

      }

      if ( isset($crypto_key) )

        unset($crypto_key); // Get this sucker out of memory fast

      if ( empty($dbport) )

        $dbport = 3306;

      if ( !defined('ENANO_INSTALLED') && !defined('MIDGET_INSTALLED') && !defined('IN_ENANO_INSTALL') )

      {

        // scriptPath isn't set yet - we need to autodetect it to avoid infinite redirects

        if ( !defined('scriptPath') )

        {

          if ( isset($_SERVER['PATH_INFO']) && !preg_match('/index\.php$/', $_SERVER['PATH_INFO']) )

          {

            $_SERVER['REQUEST_URI'] = preg_replace(';' . preg_quote($_SERVER['PATH_INFO']) . '$;', '', $_SERVER['REQUEST_URI']);

          }

          if ( !preg_match('/\.php$/', $_SERVER['REQUEST_URI']) )

          {

            // user requested http://foo/enano as opposed to http://foo/enano/index.php

            $_SERVER['REQUEST_URI'] .= '/index.php';

          }

          $sp = dirname($_SERVER['REQUEST_URI']);

          if($sp == '/' || $sp == '\\') $sp = '';

          define('scriptPath', $sp);

          define('contentPath', "$sp/index.php?title=");

        }

        $loc = scriptPath . '/install/index.php';

        define('IN_ENANO_INSTALL', 1);

        $GLOBALS['lang'] = new Language('eng');

        global $lang;

        $lang->load_file('./language/english/core.json');

        $lang->load_file('./language/english/install.json');

        // header("Location: $loc");

        redirect($loc, 'Enano not installed', 'We can\'t seem to find an Enano installation (valid config file). You will be transferred to the installation wizard momentarily...', 0);

        exit;

      }

    }

    if ( !$dbport )

      $dbport = 3306;

    if ( $dbhost && !empty($dbport) && $dbport != 3306 )

      $dbhost = '127.0.0.1';

    $host_line = ( preg_match('/^:/', $dbhost) ) ? $dbhost : "{$dbhost}:{$dbport}";

    $this->_conn = @mysql_connect($host_line, $dbuser, $dbpasswd);

    unset($dbuser);

    unset($dbpasswd); // Security

    if ( !$this->_conn && !$manual_credentials )

    {

      grinding_halt('Enano is having a problem', '<p>Error: couldn\'t connect to MySQL.<br />'.mysql_error().'</p>');

    }

    else if ( !$this->_conn && $manual_credentials )

    {

      return false;

    }

    // Reset some variables

    $this->query_backtrace = array();

    $this->query_times = array();

    $this->query_sources = array();

    $this->num_queries = 0;

    $this->debug = ( defined('ENANO_DEBUG') );

    $q = @mysql_select_db($dbname);

    if ( !$q )

    {

      if ( $manual_credentials )

        return false;

      $this->_die('The database could not be selected.');

    }

    // We're in!

    return true;

  }

  /**

   * Make a SQL query.

   * @param string Query

   * @param bool If false, skips all checks and logging stages. If you're doing a ton of queries, set this to true; in all other cases, leave at the default of false.

   * @return resource or false on failure

   */

  function sql_query($q, $log_query = true)

  {

    if ( $this->debug && function_exists('debug_backtrace') )

    {

      $backtrace = @debug_backtrace();

      if ( is_array($backtrace) )

      {

        $bt = $backtrace[0];

        if ( isset($backtrace[1]['class']) )

        {

          if ( $backtrace[1]['class'] == 'sessionManager' )

          {

            $bt = $backtrace[1];

          }

        }

        $this->query_sources[$q] = substr($bt['file'], strlen(ENANO_ROOT) + 1) . ', line ' . $bt['line'];

      }

      unset($backtrace);

    }

    $this->num_queries++;

    if ( $log_query || defined('ENANO_DEBUG') )

    {

      $this->query_backtrace[] = $q;

      $this->latest_query = $q;

    }

    // First make sure we have a connection

    if ( !$this->_conn )

    {

      $this->_die('A database connection has not yet been established.');

    }

    // Start the timer

    if ( $log_query || defined('ENANO_DEBUG') )

      $time_start = microtime_float();

    // Does this query look malicious?

    if ( $log_query || defined('ENANO_DEBUG') )

    {

      if ( !$this->check_query($q) )

      {

        $this->report_query($q);

        $debug = ( defined('ENANO_DEBUG') ) ? '<p>Query was:</p><pre>'.htmlspecialchars($q).'</pre>' : '';

        grinding_halt('SQL Injection attempt', '<p>Enano has caught and prevented an SQL injection attempt. Your IP address has been recorded and the administrator has been notified.</p>' . $debug);

      }

    }

    $r = mysql_query($q, $this->_conn);

    if ( $log_query )

      $this->query_times[$q] = microtime_float() - $time_start;

    $this->latest_result = $r;

    return $r;

  }

  /**

   * Make a SQL query, but do not have PHP buffer all the results. Useful for queries that are expected to return a huge number of results.

   * @param string Query

   * @param bool If false, skips all checks and logging stages. If you're doing a ton of queries, set this to true; in all other cases, leave at the default of false.

   * @return resource or false on failure

   */

  function sql_unbuffered_query($q, $log_query = true)

  {

    $this->num_queries++;

    if ( $log_query || defined('ENANO_DEBUG') )

      $this->query_backtrace[] = '(UNBUFFERED) ' . $q;

    $this->latest_query = $q;

    // First make sure we have a connection

    if ( !$this->_conn )

    {

      $this->_die('A database connection has not yet been established.');

    }

    // Does this query look malicious?

    if ( !$this->check_query($q) )

    {

      $this->report_query($q);

      $debug = ( defined('ENANO_DEBUG') ) ? '<p>Query was:</p><pre>'.htmlspecialchars($q).'</pre>' : '';

      grinding_halt('SQL Injection attempt', '<p>Enano has caught and prevented an SQL injection attempt. Your IP address has been recorded and the administrator has been notified.</p>' . $debug);

    }

    $time_start = microtime_float();

    $r = @mysql_unbuffered_query($q, $this->_conn);

    $this->query_times[$q] = microtime_float() - $time_start;

    $this->latest_result = $r;

    return $r;

  }

  /**

   * Performs heuristic analysis on a SQL query to check for known attack patterns.

   * @param string $q the query to check

   * @return bool true if query passed check, otherwise false

   */

  function check_query($q, $debug = false)

  {

    global $db_sql_parse_time;

    $ts = microtime_float();

    // remove properly escaped quotes

    $q = str_replace('\\\\', '', $q);

    $q = str_replace(array("\\\"", "\\'"), '', $q);

    // make sure quotes match

    foreach ( array("'", '"') as $quote )

    {

      $n_quotes = get_char_count($q, $quote);

      if ( $n_quotes % 2 == 1 )

      {

        // mismatched quotes

        if ( $debug ) echo "Found mismatched quotes in query; parsed:\n$q\n";

        return false;

      }

      // this quote is now confirmed to be matching; we can safely move all quoted strings out and replace with a token

      $q = preg_replace("/$quote(.*?)$quote/s", 'SAFE_QUOTE', $q);

    }

    $q = preg_replace("/(SAFE_QUOTE)+/", 'SAFE_QUOTE', $q);

    // quotes are now matched out. does this string have a comment marker in it?

    if ( strstr($q, '--') )

    {

      return false;

    }

    if ( preg_match('/[\s]+(SAFE_QUOTE|[\S]+)=\\1($|[\s]+)/', $q, $match) )

    {

      if ( $debug ) echo 'Found always-true test in query, injection attempt caught, match:<br />' . '<pre>' . print_r($match, true) . '</pre>';

      return false;

    }

    $ts = microtime_float() - $ts;

    $db_sql_parse_time += $ts;

    return true;

  }

  /**

   * Set the internal result pointer to X

   * @param int $pos The number of the row

   * @param resource $result The MySQL result resource - if not given, the latest cached query is assumed

   * @return true on success, false on failure

   */

  function sql_data_seek($pos, $result = false)

  {

    if ( !$result )

      $result = $this->latest_result;

    if ( !$result )

      return false;

    return mysql_data_seek($result, $pos) ? true : false;

  }

  /**

   * Reports a bad query to the admin

   * @param string $query the naughty query

   * @access private

   */

  function report_query($query)

  {

    global $session;

    if ( is_object($session) && defined('ENANO_MAINSTREAM') )

    {

      $username = $session->username;

      $user_id = $session->user_id;

    }

    else

    {

      $username = 'Unavailable';

      $user_id = 1;

    } 

    $query = $this->escape($query);

    $q = $this->sql_query('INSERT INTO '.table_prefix.'logs(log_type,     action,         time_id,    date_string, page_text,      author,            author_uid,       edit_summary)

                                                     VALUES(\'security\', \'sql_inject\', '.time().', \'\',        \''.$query.'\', \''.$username.'\', ' . $user_id . ', \''.$_SERVER['REMOTE_ADDR'].'\');');

  }

  /**

   * Returns the ID of the row last inserted.

   * @return int

   */

  function insert_id()

  {

    return @mysql_insert_id();

  }

  /**

   * Fetch one row from the given query as an associative array.

   * @param resource The resource returned from sql_query; if this isn't provided, the last result resource is used.

   * @return array

   */

  function fetchrow($r = false)

  {

    if ( !$this->_conn )

      return false;

    if ( !$r )

      $r = $this->latest_result;

    if ( !$r )

      $this->_die('$db->fetchrow(): an invalid MySQL resource was passed.');

    $row = mysql_fetch_assoc($r);

    return integerize_array($row);

  }

  /**

   * Fetch one row from the given query as a numeric array.

   * @param resource The resource returned from sql_query; if this isn't provided, the last result resource is used.

   * @return array

   */

  function fetchrow_num($r = false)

  {

    if ( !$r )

      $r = $this->latest_result;

    if ( !$r )

      $this->_die('$db->fetchrow(): an invalid MySQL resource was passed.');

    $row = mysql_fetch_row($r);

    return integerize_array($row);

  }

  /**

   * Get the number of results for a given query.

   * @param resource The resource returned from sql_query; if this isn't provided, the last result resource is used.

   * @return array

   */

  function numrows($r = false)

  {

    if ( !$r )

      $r = $this->latest_result;

    if ( !$r )

      $this->_die('$db->fetchrow(): an invalid MySQL resource was passed.');

    return mysql_num_rows($r);

  }