includes/db/DatabaseError.php

   1 <?php
   2 /**
   3  * This file contains database error classes.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @ingroup Database
  22  */
  23
  24 /**
  25  * Database error base class
  26  * @ingroup Database
  27  */
  28 class DBError extends MWException {
  29
  30         /**
  31          * @var DatabaseBase
  32          */
  33         public $db;
  34
  35         /**
  36          * Construct a database error
  37          * @param $db DatabaseBase object which threw the error
  38          * @param string $error A simple error message to be used for debugging
  39          */
  40         function __construct( DatabaseBase $db = null, $error ) {
  41                 $this->db = $db;
  42                 parent::__construct( $error );
  43         }
  44
  45         /**
  46          * @return string
  47          */
  48         function getText() {
  49                 global $wgShowDBErrorBacktrace;
  50
  51                 $s = $this->getTextContent() . "\n";
  52
  53                 if ( $wgShowDBErrorBacktrace ) {
  54                         $s .= "Backtrace:\n" . $this->getTraceAsString() . "\n";
  55                 }
  56
  57                 return $s;
  58         }
  59
  60         /**
  61          * @return string
  62          */
  63         function getHTML() {
  64                 global $wgShowDBErrorBacktrace;
  65
  66                 $s = $this->getHTMLContent();
  67
  68                 if ( $wgShowDBErrorBacktrace ) {
  69                         $s .= '<p>Backtrace:</p><pre>' . htmlspecialchars( $this->getTraceAsString() ) . '</pre>';
  70                 }
  71
  72                 return $s;
  73         }
  74
  75         /**
  76          * @return string
  77          */
  78         protected function getTextContent() {
  79                 return $this->getMessage();
  80         }
  81
  82         /**
  83          * @return string
  84          */
  85         protected function getHTMLContent() {
  86                 return '<p>' . nl2br( htmlspecialchars( $this->getMessage() ) ) . '</p>';
  87         }
  88 }
  89
  90 /**
  91  * @ingroup Database
  92  */
  93 class DBConnectionError extends DBError {
  94         public $error;
  95
  96         function __construct( DatabaseBase $db = null, $error = 'unknown error' ) {
  97                 $msg = 'DB connection error';
  98
  99                 if ( trim( $error ) != '' ) {
 100                         $msg .= ": $error";
 101                 } elseif ( $db ) {
 102                         $error = $this->db->getServer();
 103                 }
 104
 105                 parent::__construct( $db, $msg );
 106                 $this->error = $error;
 107         }
 108
 109         /**
 110          * @return bool
 111          */
 112         function useOutputPage() {
 113                 // Not likely to work
 114                 return false;
 115         }
 116
 117         /**
 118          * @param $key
 119          * @param $fallback
 120          * @return string
 121          */
 122         function msg( $key, $fallback /*[, params...] */ ) {
 123                 global $wgLang;
 124
 125                 $args = array_slice( func_get_args(), 2 );
 126
 127                 if ( $this->useMessageCache() ) {
 128                         $message = $wgLang->getMessage( $key );
 129                 } else {
 130                         $message = $fallback;
 131                 }
 132                 return wfMsgReplaceArgs( $message, $args );
 133         }
 134
 135         /**
 136          * @return boolean
 137          */
 138         function isLoggable() {
 139                 // Don't send to the exception log, already in dberror log
 140                 return false;
 141         }
 142
 143         /**
 144          * @return string
 145          */
 146         function getHTML() {
 147                 global $wgShowDBErrorBacktrace, $wgShowHostnames, $wgShowSQLErrors;
 148
 149                 $sorry = htmlspecialchars( $this->msg( 'dberr-problems', 'Sorry! This site is experiencing technical difficulties.' ) );
 150                 $again = htmlspecialchars( $this->msg( 'dberr-again', 'Try waiting a few minutes and reloading.' ) );
 151
 152                 if ( $wgShowHostnames || $wgShowSQLErrors ) {
 153                         $info = str_replace(
 154                                 '$1', Html::element( 'span', array( 'dir' => 'ltr' ), $this->error ),
 155                                 htmlspecialchars( $this->msg( 'dberr-info', '(Cannot contact the database server: $1)' ) )
 156                         );
 157                 } else {
 158                         $info = htmlspecialchars( $this->msg( 'dberr-info-hidden', '(Cannot contact the database server)' ) );
 159                 }
 160
 161                 # No database access
 162                 MessageCache::singleton()->disable();
 163
 164                 $html = "<h1>$sorry</h1><p>$again</p><p><small>$info</small></p>";
 165
 166                 if ( $wgShowDBErrorBacktrace ) {
 167                         $html .= '<p>Backtrace:</p><pre>' . htmlspecialchars( $this->getTraceAsString() ) . '</pre>';
 168                 }
 169
 170                 $html .= '<hr />';
 171                 $html .= $this->searchForm();
 172
 173                 return $html;
 174         }
 175
 176         protected function getTextContent() {
 177                 global $wgShowHostnames, $wgShowSQLErrors;
 178
 179                 if ( $wgShowHostnames || $wgShowSQLErrors ) {
 180                         return $this->getMessage();
 181                 } else {
 182                         return 'DB connection error';
 183                 }
 184         }
 185
 186         public function reportHTML() {
 187                 global $wgUseFileCache;
 188
 189                 // Check whether we can serve a file-cached copy of the page with the error underneath
 190                 if ( $wgUseFileCache ) {
 191                         try {
 192                                 $cache = $this->fileCachedPage();
 193                                 // Cached version on file system?
 194                                 if ( $cache !== null ) {
 195                                         // Hack: extend the body for error messages
 196                                         $cache = str_replace( array( '</html>', '</body>' ), '', $cache );
 197                                         // Add cache notice...
 198                                         $cache .= '<div style="border:1px solid #ffd0d0;padding:1em;">' .
 199                                                 htmlspecialchars( $this->msg( 'dberr-cachederror',
 200                                                         'This is a cached copy of the requested page, and may not be up to date.' ) ) .
 201                                                 '</div>';
 202
 203                                         // Output cached page with notices on bottom and re-close body
 204                                         echo "{$cache}<hr />{$this->getHTML()}</body></html>";
 205                                         return;
 206                                 }
 207                         } catch ( MWException $e ) {
 208                                 // Do nothing, just use the default page
 209                         }
 210                 }
 211
 212                 // We can't, cough and die in the usual fashion
 213                 parent::reportHTML();
 214         }
 215
 216         /**
 217          * @return string
 218          */
 219         function searchForm() {
 220                 global $wgSitename, $wgCanonicalServer, $wgRequest;
 221
 222                 $usegoogle = htmlspecialchars( $this->msg( 'dberr-usegoogle', 'You can try searching via Google in the meantime.' ) );
 223                 $outofdate = htmlspecialchars( $this->msg( 'dberr-outofdate', 'Note that their indexes of our content may be out of date.' ) );
 224                 $googlesearch = htmlspecialchars( $this->msg( 'searchbutton', 'Search' ) );
 225
 226                 $search = htmlspecialchars( $wgRequest->getVal( 'search' ) );
 227
 228                 $server = htmlspecialchars( $wgCanonicalServer );
 229                 $sitename = htmlspecialchars( $wgSitename );
 230
 231                 $trygoogle = <<<EOT
 232 <div style="margin: 1.5em">$usegoogle<br />
 233 <small>$outofdate</small>
 234 </div>
 235 <form method="get" action="//www.google.com/search" id="googlesearch">
 236         <input type="hidden" name="domains" value="$server" />
 237         <input type="hidden" name="num" value="50" />
 238         <input type="hidden" name="ie" value="UTF-8" />
 239         <input type="hidden" name="oe" value="UTF-8" />
 240
 241         <input type="text" name="q" size="31" maxlength="255" value="$search" />
 242         <input type="submit" name="btnG" value="$googlesearch" />
 243         <p>
 244                 <label><input type="radio" name="sitesearch" value="$server" checked="checked" />$sitename</label>
 245                 <label><input type="radio" name="sitesearch" value="" />WWW</label>
 246         </p>
 247 </form>
 248 EOT;
 249                 return $trygoogle;
 250         }
 251
 252         /**
 253          * @return string
 254          */
 255         private function fileCachedPage() {
 256                 global $wgTitle, $wgOut, $wgRequest;
 257
 258                 if ( $wgOut->isDisabled() ) {
 259                         // Done already?
 260                         return '';
 261                 }
 262
 263                 if ( $wgTitle ) {
 264                         // use $wgTitle if we managed to set it
 265                         $t = $wgTitle->getPrefixedDBkey();
 266                 } else {
 267                         // Fallback to the raw title URL param. We can't use the Title
 268                         // class is it may hit the interwiki table and give a DB error.
 269                         // We may get a cache miss due to not sanitizing the title though.
 270                         $t = str_replace( ' ', '_', $wgRequest->getVal( 'title' ) );
 271                         if ( $t == '' ) { // fallback to main page
 272                                 $t = Title::newFromText(
 273                                         $this->msg( 'mainpage', 'Main Page' ) )->getPrefixedDBkey();
 274                         }
 275                 }
 276
 277                 $cache = HTMLFileCache::newFromTitle( $t, 'view' );
 278                 if ( $cache->isCached() ) {
 279                         return $cache->fetchText();
 280                 } else {
 281                         return '';
 282                 }
 283         }
 284 }
 285
 286 /**
 287  * @ingroup Database
 288  */
 289 class DBQueryError extends DBError {
 290         public $error, $errno, $sql, $fname;
 291
 292         /**
 293          * @param $db DatabaseBase
 294          * @param $error string
 295          * @param $errno int|string
 296          * @param $sql string
 297          * @param $fname string
 298          */
 299         function __construct( DatabaseBase $db, $error, $errno, $sql, $fname ) {
 300                 $message = "A database error has occurred. Did you forget to run maintenance/update.php after upgrading?  See: https://www.mediawiki.org/wiki/Manual:Upgrading#Run_the_update_script\n" .
 301                         "Query: $sql\n" .
 302                         "Function: $fname\n" .
 303                         "Error: $errno $error\n";
 304                 parent::__construct( $db, $message );
 305
 306                 $this->error = $error;
 307                 $this->errno = $errno;
 308                 $this->sql = $sql;
 309                 $this->fname = $fname;
 310         }
 311
 312         /**
 313          * @return boolean
 314          */
 315         function isLoggable() {
 316                 // Don't send to the exception log, already in dberror log
 317                 return false;
 318         }
 319
 320         /**
 321          * @return string
 322          */
 323         function getPageTitle() {
 324                 return $this->msg( 'databaseerror', 'Database error' );
 325         }
 326
 327         /**
 328          * @return string
 329          */
 330         protected function getHTMLContent() {
 331                 $key = 'databaseerror-text';
 332                 $s = Html::element( 'p', array(), $this->msg( $key, $this->getFallbackMessage( $key ) ) );
 333
 334                 $details = $this->getTechnicalDetails();
 335                 if ( $details ) {
 336                         $s .= '<ul>';
 337                         foreach ( $details as $key => $detail ) {
 338                                 $s .= str_replace(
 339                                         '$1', call_user_func_array( 'Html::element', $detail ),
 340                                         Html::element( 'li', array(),
 341                                                 $this->msg( $key, $this->getFallbackMessage( $key ) )
 342                                         )
 343                                 );
 344                         }
 345                         $s .= '</ul>';
 346                 }
 347
 348                 return $s;
 349         }
 350
 351         /**
 352          * @return string
 353          */
 354         protected function getTextContent() {
 355                 $key = 'databaseerror-textcl';
 356                 $s = $this->msg( $key, $this->getFallbackMessage( $key ) ) . "\n";
 357
 358                 foreach ( $this->getTechnicalDetails() as $key => $detail ) {
 359                         $s .= $this->msg( $key, $this->getFallbackMessage( $key ), $detail[2] ) . "\n";
 360                 }
 361
 362                 return $s;
 363         }
 364
 365         /**
 366          * Make a list of technical details that can be shown to the user. This information can
 367          * aid in debugging yet may be useful to an attacker trying to exploit a security weakness
 368          * in the software or server configuration.
 369          *
 370          * Thus no such details are shown by default, though if $wgShowHostnames is true, only the
 371          * full SQL query is hidden; in fact, the error message often does contain a hostname, and
 372          * sites using this option probably don't care much about "security by obscurity". Of course,
 373          * if $wgShowSQLErrors is true, the SQL query *is* shown.
 374          *
 375          * @return array: Keys are message keys; values are arrays of arguments for Html::element().
 376          *   Array will be empty if users are not allowed to see any of these details at all.
 377          */
 378         protected function getTechnicalDetails() {
 379                 global $wgShowHostnames, $wgShowSQLErrors;
 380
 381                 $attribs = array( 'dir' => 'ltr' );
 382                 $details = array();
 383
 384                 if ( $wgShowSQLErrors ) {
 385                         $details['databaseerror-query'] = array(
 386                                 'div', array( 'class' => 'mw-code' ) + $attribs, $this->sql );
 387                 }
 388
 389                 if ( $wgShowHostnames || $wgShowSQLErrors ) {
 390                         $errorMessage = $this->errno . ' ' . $this->error;
 391                         $details['databaseerror-function'] = array( 'code', $attribs, $this->fname );
 392                         $details['databaseerror-error'] = array( 'samp', $attribs, $errorMessage );
 393                 }
 394
 395                 return $details;
 396         }
 397
 398         /**
 399          * @param string $key Message key
 400          * @return string: English message text
 401          */
 402         private function getFallbackMessage( $key ) {
 403                 $messages = array(
 404                         'databaseerror-text' => 'A database query error has occurred.
 405 This may indicate a bug in the software.',
 406                         'databaseerror-textcl' => 'A database query error has occurred.',
 407                         'databaseerror-query' => 'Query: $1',
 408                         'databaseerror-function' => 'Function: $1',
 409                         'databaseerror-error' => 'Error: $1',
 410                 );
 411                 return $messages[$key];
 412         }
 413
 414 }
 415
 416 /**
 417  * @ingroup Database
 418  */
 419 class DBUnexpectedError extends DBError {}