includes/dbal.php
changeset 1 fe660c52c48f
child 15 ad5986a53197
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/includes/dbal.php	Wed Jun 13 16:07:17 2007 -0400
@@ -0,0 +1,598 @@
+<?php
+
+/*
+ * Enano - an open-source CMS capable of wiki functions, Drupal-like sidebar blocks, and everything in between
+ * Version 1.0 (Banshee)
+ * Copyright (C) 2006-2007 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();
+  $debug = $debug[2]['file'] . ', line ' . $debug[2]['line'];
+  echo "<b>$errtype:</b> $errstr<br />Error source:<pre>$debug</pre>";
+}
+ 
+class mysql {
+  var $num_queries, $query_backtrace, $latest_result, $latest_query, $_conn, $sql_stack_fields, $sql_stack_values;
+  var $row = array();
+	var $rowset = array();
+  var $errhandler;
+  
+  function enable_errorhandler()
+  {
+    if ( function_exists('debug_backtrace') )
+    {
+      $this->errhandler = set_error_handler('db_error_handler');
+    }
+  }
+  
+  function disable_errorhandler()
+  {
+    if ( $this->errhandler )
+    {
+      set_error_handler($this->errhandler);
+    }
+    else
+    {
+      restore_error_handler();
+    }
+  }
+  
+  function sql_backtrace() {
+    $qb = explode("\n", $this->query_backtrace);
+    $bt = '';
+    //for($i=sizeof($qb)-1;$i>=0;$i--) {
+    for($i=0;$i<sizeof($qb);$i++) {
+      $bt .= $qb[$i]."\n";
+    }
+    return $bt;
+  }
+  
+  function ensure_connection()
+  {
+    if(!$this->_conn)
+    {
+      $this->connect();
+    }
+  }
+  
+  function _die($t = '') {
+    if(defined('ENANO_HEADERS_SENT')) {
+      ob_clean();
+    }
+    header('HTTP/1.1 500 Internal Server Error');
+    $bt = $this->sql_backtrace();
+    $e = htmlspecialchars(mysql_error());
+    if($e=='') $e='&lt;none&gt;';
+    if(defined('ENANO_CONFIG_FETCHED')) die_semicritical('Database error', '<h3>An error occurred during a database query.</h3><p>'.$t.'<br />Error returned by MySQL: '.$e.'<br />SQL Backtrace:</p><pre>'.$bt.'</pre>');
+    else                                   grinding_halt('Database error', '<h3>An error occurred during a database query.</h3><p>'.$t.'<br />Error returned by MySQL: '.$e.'<br />SQL Backtrace:</p><pre>'.$bt.'</pre>');
+    exit;
+  }
+  
+  function die_json()
+  {
+    $e = addslashes(htmlspecialchars(mysql_error()));
+    $q = addslashes($this->latest_query);
+    $t = "{'mode':'error','error':'An error occurred during database query.\nQuery was:\n  $q\n\nError returned by MySQL: $e'}";
+    die($t);
+  }
+  
+  function get_error($t = '') {
+    header('HTTP/1.1 500 Internal Server Error');
+    $bt = $this->sql_backtrace();
+    $e = htmlspecialchars(mysql_error());
+    if($e=='') $e='&lt;none&gt;';
+    $text = '<h3>An error occurred during a database query.</h3><p>'.$t.'<br />Error returned by MySQL: '.$e.'<br />SQL Backtrace:</p><pre>'.$bt.'</pre>';
+    return $text;
+  }
+  
+  function connect() {
+    $this->enable_errorhandler();
+    dc_here('dbal: trying to connect....');
+    @include(ENANO_ROOT.'/config.php');
+    if(isset($crypto_key))
+      unset($crypto_key); // Get this sucker out of memory fast
+    if(!defined('ENANO_INSTALLED') && !defined('MIDGET_INSTALLED') && !defined('IN_ENANO_INSTALL') )
+    {
+      dc_here('dbal: oops, looks like Enano isn\'t set up. Constants ENANO_INSTALLED, MIDGET_INSTALLED, and IN_ENANO_INSTALL are all undefined.');
+      header('Location: install.php'); 
+      exit;
+    }
+    $this->_conn = @mysql_connect($dbhost, $dbuser, $dbpasswd);
+    unset($dbuser);
+    unset($dbpasswd); // Security
+    if(!$this->_conn) { dc_here('dbal: uhoh!<br />'.mysql_error()); grinding_halt('Enano is having a problem', '<p>Error: couldn\'t connect to MySQL.<br />'.mysql_error().'</p>'); }
+    $this->query_backtrace = '';
+    $this->num_queries = 0;
+    dc_here('dbal: we\'re in, selecting database...');
+    $q = $this->sql_query('USE '.$dbname.';');
+    if(!$q) $this->_die('The database could not be selected.');
+    dc_here('dbal: connected to MySQL');
+    $this->disable_errorhandler();
+  }
+  
+  function sql_query($q) {
+    $this->enable_errorhandler();
+    $this->num_queries++;
+    $this->query_backtrace .= $q."\n";
+    $this->latest_query = $q;
+    dc_here('dbal: making SQL query:<br /><tt>'.$q.'</tt>');
+    if(!$this->_conn) $this->_die('A database connection has not yet been established.');
+    if(!$this->check_query($q))
+    {
+      $this->report_query($q);
+      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><p>Query was:</p><pre>'.htmlspecialchars($q).'</pre>');
+    }
+    $r = mysql_query($q, $this->_conn);
+    $this->latest_result = $r;
+    $this->disable_errorhandler();
+    return $r;
+  }
+  
+  function sql_unbuffered_query($q) {
+    $this->enable_errorhandler();
+    $this->num_queries++;
+    $this->query_backtrace .= '(UNBUFFERED) ' . $q."\n";
+    $this->latest_query = $q;
+    dc_here('dbal: making SQL query:<br /><tt>'.$q.'</tt>');
+    if(!$this->_conn) $this->_die('A database connection has not yet been established.');
+    if(!$this->check_query($q))
+    {
+      $this->report_query($q);
+      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><p>Query was:</p><pre>'.htmlspecialchars($q).'</pre>');
+    }
+    $r = mysql_unbuffered_query($q, $this->_conn);
+    $this->latest_result = $r;
+    $this->disable_errorhandler();
+    return $r;
+  }
+  
+  /**
+   * Checks a SQL query for possible signs of injection attempts
+   * @param string $q the query to check
+   * @return bool true if query passed check, otherwise false
+   */
+  
+  function check_query($q, $debug = false)
+  {
+    if($debug) echo "\$db-&gt;check_query(): checking query: ".htmlspecialchars($q).'<br />'."\n";
+    $sz = strlen($q);
+    $quotechar = false;
+    $quotepos  = 0;
+    $prev_is_quote = false;
+    $just_started = false;
+    for($i=0;$i<strlen($q);$i++,$c=substr($q, $i, 1))
+    {
+      $next = substr($q, $i+1, 1);
+      $next2 = substr($q, $i+2, 1);
+      $prev = substr($q, $i-1, 1);
+      $prev2 = substr($q, $i-2, 1);
+      if(isset($c) && in_array($c, Array('"', "'", '`')))
+      {
+        if($quotechar)
+        {
+          if(
+              ( $quotechar == $c && $quotechar != $next && ( $quotechar != $prev || $just_entered ) && $prev != '\\') ||
+              ( $prev2 == '\\' && $prev == $quotechar && $quotechar == $c )
+            )
+          {
+            $quotechar = false;
+            if($debug) echo('$db-&gt;check_query(): just finishing a quote section, quoted string: '.htmlspecialchars(substr($q, $quotepos, $i - $quotepos + 1)) . '<br />');
+            $q = substr($q, 0, $quotepos) . 'SAFE_QUOTE' . substr($q, $i + 1, strlen($q));
+            if($debug) echo('$db-&gt;check_query(): Filtered query: '.$q.'<br />');
+            $i = $quotepos;
+          }
+        }
+        else
+        {
+          $quotechar = $c;
+          $quotepos  = $i;
+          $just_entered = true;
+        }
+        if($debug) echo '$db-&gt;check_query(): found quote char as pos: '.$i.'<br />';
+        continue;
+      }
+      $just_entered = false;
+    }
+    if(substr(trim($q), strlen(trim($q))-1, 1) == ';') $q = substr(trim($q), 0, strlen(trim($q))-1);
+    for($i=0;$i<strlen($q);$i++,$c=substr($q, $i, 1))
+    {
+      if( ( $c == ';' && $i != $sz-1 ) || $c . substr($q, $i+1, 1) == '--') // Don't permit semicolons in mid-query, and never allow comments
+      {
+        // Injection attempt!
+        if($debug)
+        {
+          $e = '';
+          for($j=$i-5;$j<$i+5;$j++)
+          {
+            if($j == $i) $e .= '<span style="color: red; text-decoration: underline;">' . $c . '</span>';
+            else $e .= $c;
+          }
+          echo 'Injection attempt caught at pos: '.$i.'<br />';
+        }
+        return false;
+      }
+    }
+    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)
+  {
+    $this->enable_errorhandler();
+    if(!$result)
+      $result = $this->latest_result;
+    if(!$result)
+    {
+      $this->disable_errorhandler();
+      return false;
+    }
+    if(mysql_data_seek($result, $pos))
+    {
+      $this->disable_errorhandler();
+      return true;
+    }
+    else
+    {
+      $this->disable_errorhandler();
+      return 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;
+    else
+      $username = 'Unavailable';
+    $query = $this->escape($query);
+    $q = $this->sql_query('INSERT INTO '.table_prefix.'logs(log_type,     action,         time_id,    date_string, page_text,      author,            edit_summary)
+                                                     VALUES(\'security\', \'sql_inject\', '.time().', \'\',        \''.$query.'\', \''.$username.'\', \''.$_SERVER['REMOTE_ADDR'].'\');');
+  }
+  
+  function fetchrow($r = false) {
+    $this->enable_errorhandler();
+    if(!$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);
+    $this->disable_errorhandler();
+    return $row;
+  }
+  
+  function fetchrow_num($r = false) {
+    $this->enable_errorhandler();
+    if(!$r) $r = $this->latest_result;
+    if(!$r) $this->_die('$db->fetchrow(): an invalid MySQL resource was passed.');
+    $row = mysql_fetch_row($r);
+    $this->disable_errorhandler();
+    return $row;
+  }
+  
+  function numrows($r = false) {
+    $this->enable_errorhandler();
+    if(!$r) $r = $this->latest_result;
+    if(!$r) $this->_die('$db->fetchrow(): an invalid MySQL resource was passed.');
+    $n = mysql_num_rows($r);
+    $this->disable_errorhandler();
+    return $n;
+  }
+  
+  function escape($str)
+  {
+    $this->enable_errorhandler();
+    $str = mysql_real_escape_string($str);
+    $this->disable_errorhandler();
+    return $str;
+  }
+  
+  function free_result($result = false)
+  {
+    $this->enable_errorhandler();
+    if(!$result)
+      $result = $this->latest_result;
+    if(!$result)
+    {
+      $this->disable_errorhandler();
+      return null;
+    }
+    mysql_free_result($result);
+    $this->disable_errorhandler();
+    return null;
+  }
+  
+  function close() {
+    dc_here('dbal: closing MySQL connection');
+    mysql_close($this->_conn);
+    unset($this->_conn);
+  }
+  
+  // phpBB DBAL compatibility
+  function sql_fetchrow($r = false)
+  {
+    return $this->fetchrow($r);
+  }
+  function sql_freeresult($r = false)
+  {
+    if(!$this->_conn) return false;
+    if(!$r) $r = $this->latest_result;
+    if(!$r) $this->_die('$db->fetchrow(): an invalid MySQL resource was passed.');
+    mysql_free_result($r);
+  }
+  function sql_numrows($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.');
+    return mysql_num_rows($r);
+  }
+  function sql_affectedrows($r = false, $f, $n)
+  {
+    if(!$this->_conn) return false;
+    if(!$r) $r = $this->latest_result;
+    if(!$r) $this->_die('$db->fetchrow(): an invalid MySQL resource was passed.');
+    return mysql_affected_rows();
+  }
+  
+  function sql_type_cast(&$value)
+	{
+		if ( is_float($value) )
+		{
+			return doubleval($value);
+		}
+		if ( is_integer($value) || is_bool($value) )
+		{
+			return intval($value);
+		}
+		if ( is_string($value) || empty($value) )
+		{
+			return '\'' . $this->sql_escape_string($value) . '\'';
+		}
+		// uncastable var : let's do a basic protection on it to prevent sql injection attempt
+		return '\'' . $this->sql_escape_string(htmlspecialchars($value)) . '\'';
+	}
+
+	function sql_statement(&$fields, $fields_inc='')
+	{
+		// init result
+		$this->sql_fields = $this->sql_values = $this->sql_update = '';
+		if ( empty($fields) && empty($fields_inc) )
+		{
+			return;
+		}
+
+		// process
+		if ( !empty($fields) )
+		{
+			$first = true;
+			foreach ( $fields as $field => $value )
+			{
+				// field must contain a field name
+				if ( !empty($field) && is_string($field) )
+				{
+					$value = $this->sql_type_cast($value);
+					$this->sql_fields .= ( $first ? '' : ', ' ) . $field;
+					$this->sql_values .= ( $first ? '' : ', ' ) . $value;
+					$this->sql_update .= ( $first ? '' : ', ' ) . $field . ' = ' . $value;
+					$first = false;
+				}
+			}
+		}
+		if ( !empty($fields_inc) )
+		{
+			foreach ( $fields_inc as $field => $indent )
+			{
+				if ( $indent != 0 )
+				{
+					$this->sql_update .= (empty($this->sql_update) ? '' : ', ') . $field . ' = ' . $field . ($indent < 0 ? ' - ' : ' + ') . abs($indent);
+				}
+			}
+		}
+	}
+
+	function sql_stack_reset($id='')
+	{
+		if ( empty($id) )
+		{
+			$this->sql_stack_fields = array();
+			$this->sql_stack_values = array();
+		}
+		else
+		{
+			$this->sql_stack_fields[$id] = array();
+			$this->sql_stack_values[$id] = array();
+		}
+	}
+
+	function sql_stack_statement(&$fields, $id='')
+	{
+		$this->sql_statement($fields);
+		if ( empty($id) )
+		{
+			$this->sql_stack_fields = $this->sql_fields;
+			$this->sql_stack_values[] = '(' . $this->sql_values . ')';
+		}
+		else
+		{
+			$this->sql_stack_fields[$id] = $this->sql_fields;
+			$this->sql_stack_values[$id][] = '(' . $this->sql_values . ')';
+		}
+	}
+
+	function sql_stack_insert($table, $transaction=false, $line='', $file='', $break_on_error=true, $id='')
+	{
+		if ( (empty($id) && empty($this->sql_stack_values)) || (!empty($id) && empty($this->sql_stack_values[$id])) )
+		{
+			return false;
+		}
+		switch( SQL_LAYER )
+		{
+			case 'mysql':
+			case 'mysql4':
+				if ( empty($id) )
+				{
+					$sql = 'INSERT INTO ' . $table . '
+								(' . $this->sql_stack_fields . ') VALUES ' . implode(",\n", $this->sql_stack_values);
+				}
+				else
+				{
+					$sql = 'INSERT INTO ' . $table . '
+								(' . $this->sql_stack_fields[$id] . ') VALUES ' . implode(",\n", $this->sql_stack_values[$id]);
+				}
+				$this->sql_stack_reset($id);
+				return $this->sql_query($sql, $transaction, $line, $file, $break_on_error);
+				break;
+			default:
+				$count_sql_stack_values = empty($id) ? count($this->sql_stack_values) : count($this->sql_stack_values[$id]);
+				$result = !empty($count_sql_stack_values);
+				for ( $i = 0; $i < $count_sql_stack_values; $i++ )
+				{
+					if ( empty($id) )
+					{
+						$sql = 'INSERT INTO ' . $table . '
+									(' . $this->sql_stack_fields . ') VALUES ' . $this->sql_stack_values[$i];
+					}
+					else
+					{
+						$sql = 'INSERT INTO ' . $table . '
+									(' . $this->sql_stack_fields[$id] . ') VALUES ' . $this->sql_stack_values[$id][$i];
+					}
+					$result &= $this->sql_query($sql, $transaction, $line, $file, $break_on_error);
+				}
+				$this->sql_stack_reset($id);
+				return $result;
+				break;
+		}
+	}
+
+	function sql_subquery($field, $sql, $line='', $file='', $break_on_error=true, $type=TYPE_INT)
+	{
+		// sub-queries doable
+		$this->sql_get_version();
+		if ( !in_array(SQL_LAYER, array('mysql', 'mysql4')) || (($this->sql_version[0] + ($this->sql_version[1] / 100)) >= 4.01) )
+		{
+			return $sql;
+		}
+
+		// no sub-queries
+		$ids = array();
+		$result = $this->sql_query(trim($sql), false, $line, $file, $break_on_error);
+		while ( $row = $this->sql_fetchrow($result) )
+		{
+			$ids[] = $type == TYPE_INT ? intval($row[$field]) : '\'' . $this->sql_escape_string($row[$field]) . '\'';
+		}
+		$this->sql_freeresult($result);
+		return empty($ids) ? 'NULL' : implode(', ', $ids);
+	}
+
+	function sql_col_id($expr, $alias)
+	{
+		$this->sql_get_version();
+		return in_array(SQL_LAYER, array('mysql', 'mysql4')) && (($this->sql_version[0] + ($this->sql_version[1] / 100)) <= 4.01) ? $alias : $expr;
+	}
+
+	function sql_get_version()
+	{
+		if ( empty($this->sql_version) )
+		{
+			$this->sql_version = array(0, 0, 0);
+			switch ( SQL_LAYER )
+			{
+				case 'mysql':
+				case 'mysql4':
+					if ( function_exists('mysql_get_server_info') )
+					{
+						$lo_version = explode('-', mysql_get_server_info());
+						$this->sql_version = explode('.', $lo_version[0]);
+						$this->sql_version = array(intval($this->sql_version[0]), intval($this->sql_version[1]), intval($this->sql_version[2]), $lo_version[1]);
+					}
+					break;
+
+				case 'postgresql':
+				case 'mssql':
+				case 'mssql-odbc':
+				default:
+					break;
+			}
+		}
+		return $this->sql_version;
+	}
+
+	function sql_error()
+	{
+		if ( $this->_conn )
+		{
+			return mysql_error();
+		}
+		else
+		{
+			return array();
+		}
+	}
+  function sql_escape_string($t) 
+  {
+    return mysql_real_escape_string($t);
+  }
+  function sql_close()
+  {
+    $this->close();
+  }
+  function sql_fetchrowset($query_id = 0)
+	{
+		if( !$query_id )
+		{
+			$query_id = $this->query_result;
+		}
+
+		if( $query_id )
+		{
+			unset($this->rowset[$query_id]);
+			unset($this->row[$query_id]);
+
+			while($this->rowset[$query_id] = mysql_fetch_array($query_id, MYSQL_ASSOC))
+			{
+				$result[] = $this->rowset[$query_id];
+			}
+
+			return $result;
+		}
+		else
+		{
+			return false;
+		}
+	}
+}
+
+?>