CRM/Utils/Check/Security.php

   1 <?php
   2 /*
   3  +--------------------------------------------------------------------+
   4  | CiviCRM version 4.7                                                |
   5  +--------------------------------------------------------------------+
   6  | Copyright CiviCRM LLC (c) 2004-2015                                |
   7  +--------------------------------------------------------------------+
   8  | This file is a part of CiviCRM.                                    |
   9  |                                                                    |
  10  | CiviCRM is free software; you can copy, modify, and distribute it  |
  11  | under the terms of the GNU Affero General Public License           |
  12  | Version 3, 19 November 2007 and the CiviCRM Licensing Exception.   |
  13  |                                                                    |
  14  | CiviCRM is distributed in the hope that it will be useful, but     |
  15  | WITHOUT ANY WARRANTY; without even the implied warranty of         |
  16  | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.               |
  17  | See the GNU Affero General Public License for more details.        |
  18  |                                                                    |
  19  | You should have received a copy of the GNU Affero General Public   |
  20  | License and the CiviCRM Licensing Exception along                  |
  21  | with this program; if not, contact CiviCRM LLC                     |
  22  | at info[AT]civicrm[DOT]org. If you have questions about the        |
  23  | GNU Affero General Public License or the licensing of CiviCRM,     |
  24  | see the CiviCRM license FAQ at http://civicrm.org/licensing        |
  25  +--------------------------------------------------------------------+
  26  */
  27
  28 /**
  29  *
  30  * @package CRM
  31  * @copyright CiviCRM LLC (c) 2004-2015
  32  */
  33 class CRM_Utils_Check_Security {
  34
  35   /**
  36    * CMS have a different pattern to their default file path and URL.
  37    *
  38    * @todo This function might be better shared in CRM_Utils_Check
  39    * class, but that class doesn't yet exist.
  40    */
  41   public function getFilePathMarker() {
  42     $config = CRM_Core_Config::singleton();
  43     switch ($config->userFramework) {
  44       case 'Joomla':
  45         return '/media/';
  46
  47       default:
  48         return '/files/';
  49     }
  50   }
  51
  52   /**
  53    * Run all checks in this class.
  54    *
  55    * @return array<CRM_Utils_Check_Message>
  56    */
  57   public function checkAll() {
  58     $messages = array_merge(
  59       $this->checkCxnOverrides(),
  60       $this->checkLogFileIsNotAccessible(),
  61       $this->checkUploadsAreNotAccessible(),
  62       $this->checkDirectoriesAreNotBrowseable(),
  63       $this->checkFilesAreNotPresent()
  64     );
  65     return $messages;
  66   }
  67
  68   /**
  69    * Check if our logfile is directly accessible.
  70    *
  71    * Per CiviCRM default the logfile sits in a folder which is
  72    * web-accessible, and is protected by a default .htaccess
  73    * configuration. If server config causes the .htaccess not to
  74    * function as intended, there may be information disclosure.
  75    *
  76    * The debug log may be jam-packed with sensitive data, we don't
  77    * want that.
  78    *
  79    * Being able to be retrieved directly doesn't mean the logfile
  80    * is browseable or visible to search engines; it means it can be
  81    * requested directly.
  82    *
  83    * @return array
  84    *   Array of messages
  85    * @see CRM-14091
  86    */
  87   public function checkLogFileIsNotAccessible() {
  88     $messages = array();
  89
  90     $config = CRM_Core_Config::singleton();
  91
  92     $log = CRM_Core_Error::createDebugLogger();
  93     $log_filename = str_replace('\\', '/', $log->_filename);
  94
  95     $filePathMarker = $this->getFilePathMarker();
  96
  97     // Hazard a guess at the URL of the logfile, based on common
  98     // CiviCRM layouts.
  99     if ($upload_url = explode($filePathMarker, $config->imageUploadURL)) {
 100       $url[] = $upload_url[0];
 101       if ($log_path = explode($filePathMarker, $log_filename)) {
 102         // CRM-17149: check if debug log path includes $filePathMarker
 103         if (count($log_path) > 1) {
 104           $url[] = $log_path[1];
 105           $log_url = implode($filePathMarker, $url);
 106           $headers = @get_headers($log_url);
 107           if (stripos($headers[0], '200')) {
 108             $docs_url = $this->createDocUrl('checkLogFileIsNotAccessible');
 109             $msg = 'The <a href="%1">CiviCRM debug log</a> should not be downloadable.'
 110               . '<br />' .
 111               '<a href="%2">Read more about this warning</a>';
 112             $messages[] = new CRM_Utils_Check_Message(
 113               __FUNCTION__,
 114               ts($msg, array(1 => $log_url, 2 => $docs_url)),
 115               ts('Security Warning'),
 116               \Psr\Log\LogLevel::WARNING,
 117               'fa-lock'
 118             );
 119           }
 120         }
 121       }
 122     }
 123
 124     return $messages;
 125   }
 126
 127   /**
 128    * Check if our uploads directory has accessible files.
 129    *
 130    * We'll test a handful of files randomly. Hazard a guess at the URL
 131    * of the uploads dir, based on common CiviCRM layouts. Try and
 132    * request the files, and if any are successfully retrieved, warn.
 133    *
 134    * Being retrievable doesn't mean the files are browseable or visible
 135    * to search engines; it only means they can be requested directly.
 136    *
 137    * @return array
 138    *   Array of messages
 139    * @see CRM-14091
 140    *
 141    * @todo Test with WordPress, Joomla.
 142    */
 143   public function checkUploadsAreNotAccessible() {
 144     $messages = array();
 145
 146     $config = CRM_Core_Config::singleton();
 147     $privateDirs = array(
 148       $config->uploadDir,
 149       $config->customFileUploadDir,
 150     );
 151
 152     foreach ($privateDirs as $privateDir) {
 153       $heuristicUrl = $this->guessUrl($privateDir);
 154       if ($this->isDirAccessible($privateDir, $heuristicUrl)) {
 155         $messages[] = new CRM_Utils_Check_Message(
 156           __FUNCTION__,
 157           ts('Files in the data directory (<a href="%3">%2</a>) should not be downloadable.'
 158             . '<br />'
 159             . '<a href="%1">Read more about this warning</a>',
 160             array(
 161               1 => $this->createDocUrl('checkUploadsAreNotAccessible'),
 162               2 => $privateDir,
 163               3 => $heuristicUrl,
 164             )),
 165           ts('Private Files Readable'),
 166           \Psr\Log\LogLevel::WARNING,
 167           'fa-lock'
 168         );
 169       }
 170     }
 171
 172     return $messages;
 173   }
 174
 175   /**
 176    * Check if our uploads or ConfigAndLog directories have browseable
 177    * listings.
 178    *
 179    * Retrieve a listing of files from the local filesystem, and the
 180    * corresponding path via HTTP. Then check and see if the local
 181    * files are represented in the HTTP result; if so then warn. This
 182    * MAY trigger false positives (if you have files named 'a', 'e'
 183    * we'll probably match that).
 184    *
 185    * @return array
 186    *   Array of messages
 187    * @see CRM-14091
 188    *
 189    * @todo Test with WordPress, Joomla.
 190    */
 191   public function checkDirectoriesAreNotBrowseable() {
 192     $messages = array();
 193     $config = CRM_Core_Config::singleton();
 194     $publicDirs = array(
 195       $config->imageUploadDir => $config->imageUploadURL,
 196     );
 197
 198     // Setup index.html files to prevent browsing
 199     foreach ($publicDirs as $publicDir => $publicUrl) {
 200       CRM_Utils_File::restrictBrowsing($publicDir);
 201     }
 202
 203     // Test that $publicDir is not browsable
 204     foreach ($publicDirs as $publicDir => $publicUrl) {
 205       if ($this->isBrowsable($publicDir, $publicUrl)) {
 206         $msg = 'Directory <a href="%1">%2</a> should not be browseable via the web.'
 207           . '<br />' .
 208           '<a href="%3">Read more about this warning</a>';
 209         $docs_url = $this->createDocUrl('checkDirectoriesAreNotBrowseable');
 210         $messages[] = new CRM_Utils_Check_Message(
 211           __FUNCTION__,
 212           ts($msg, array(1 => $publicDir, 2 => $publicDir, 3 => $docs_url)),
 213           ts('Browseable Directories'),
 214           \Psr\Log\LogLevel::ERROR,
 215           'fa-lock'
 216         );
 217       }
 218     }
 219
 220     return $messages;
 221   }
 222
 223
 224   /**
 225    * Check that some files are not present.
 226    *
 227    * These files have generally been deleted but Civi source tree but could be
 228    * left online if one does a faulty upgrade.
 229    *
 230    * @return array of messages
 231    */
 232   public function checkFilesAreNotPresent() {
 233     global $civicrm_root;
 234
 235     $messages = array();
 236     $files = array(
 237       array(
 238         // CRM-16005, upgraded from Civi <= 4.5.6
 239         "{$civicrm_root}/packages/dompdf/dompdf.php",
 240         \Psr\Log\LogLevel::CRITICAL,
 241       ),
 242       array(
 243         // CRM-16005, Civi >= 4.5.7
 244         "{$civicrm_root}/packages/vendor/dompdf/dompdf/dompdf.php",
 245         \Psr\Log\LogLevel::CRITICAL,
 246       ),
 247       array(
 248         // CRM-16005, Civi >= 4.6.0
 249         "{$civicrm_root}/vendor/dompdf/dompdf/dompdf.php",
 250         \Psr\Log\LogLevel::CRITICAL,
 251       ),
 252       array(
 253         // CIVI-SA-2013-001
 254         "{$civicrm_root}/packages/OpenFlashChart/php-ofc-library/ofc_upload_image.php",
 255         \Psr\Log\LogLevel::CRITICAL,
 256       ),
 257       array(
 258         "{$civicrm_root}/packages/html2text/class.html2text.inc",
 259         \Psr\Log\LogLevel::CRITICAL,
 260       ),
 261     );
 262     foreach ($files as $file) {
 263       if (file_exists($file[0])) {
 264         $messages[] = new CRM_Utils_Check_Message(
 265           __FUNCTION__,
 266           ts('File \'%1\' presents a security risk and should be deleted.', array(1 => $file)),
 267           ts('Unsafe Files'),
 268           $file[1],
 269           'fa-lock'
 270         );
 271       }
 272     }
 273     return $messages;
 274   }
 275
 276   /**
 277    * Check that the sysadmin has not modified the Cxn
 278    * security setup.
 279    */
 280   public function checkCxnOverrides() {
 281     $list = array();
 282     if (defined('CIVICRM_CXN_CA') && CIVICRM_CXN_CA !== 'CiviRootCA') {
 283       $list[] = 'CIVICRM_CXN_CA';
 284     }
 285     if (defined('CIVICRM_CXN_APPS_URL') && CIVICRM_CXN_APPS_URL !== \Civi\Cxn\Rpc\Constants::OFFICIAL_APPMETAS_URL) {
 286       $list[] = 'CIVICRM_CXN_APPS_URL';
 287     }
 288
 289     $messages = array();
 290
 291     if (!empty($list)) {
 292       $messages[] = new CRM_Utils_Check_Message(
 293         __FUNCTION__,
 294         ts('The system administrator has disabled security settings (%1). Connections to remote applications are insecure.', array(
 295           1 => implode(', ', $list),
 296         )),
 297         ts('Security Warning'),
 298         \Psr\Log\LogLevel::WARNING,
 299         'fa-lock'
 300       );
 301     }
 302
 303     return $messages;
 304   }
 305
 306   /**
 307    * Determine whether $url is a public, browsable listing for $dir
 308    *
 309    * @param string $dir
 310    *   Local dir path.
 311    * @param string $url
 312    *   Public URL.
 313    * @return bool
 314    */
 315   public function isBrowsable($dir, $url) {
 316     if (empty($dir) || empty($url) || !is_dir($dir)) {
 317       return FALSE;
 318     }
 319
 320     $result = FALSE;
 321     $file = 'delete-this-' . CRM_Utils_String::createRandom(10, CRM_Utils_String::ALPHANUMERIC);
 322
 323     // this could be a new system with no uploads (yet) -- so we'll make a file
 324     file_put_contents("$dir/$file", "delete me");
 325     $content = @file_get_contents("$url");
 326     if (stristr($content, $file)) {
 327       $result = TRUE;
 328     }
 329     unlink("$dir/$file");
 330
 331     return $result;
 332   }
 333
 334   /**
 335    * Determine whether $url is a public version of $dir in which files
 336    * are remotely accessible.
 337    *
 338    * @param string $dir
 339    *   Local dir path.
 340    * @param string $url
 341    *   Public URL.
 342    * @return bool
 343    */
 344   public function isDirAccessible($dir, $url) {
 345     $dir = rtrim($dir, '/');
 346     $url = rtrim($url, '/');
 347     if (empty($dir) || empty($url) || !is_dir($dir)) {
 348       return FALSE;
 349     }
 350
 351     $result = FALSE;
 352     $file = 'delete-this-' . CRM_Utils_String::createRandom(10, CRM_Utils_String::ALPHANUMERIC);
 353
 354     // this could be a new system with no uploads (yet) -- so we'll make a file
 355     file_put_contents("$dir/$file", "delete me");
 356
 357     $headers = @get_headers("$url/$file");
 358     if (stripos($headers[0], '200')) {
 359       $content = @file_get_contents("$url/$file");
 360       if (preg_match('/delete me/', $content)) {
 361         $result = TRUE;
 362       }
 363     }
 364
 365     unlink("$dir/$file");
 366
 367     return $result;
 368   }
 369
 370   /**
 371    * @param $topic
 372    *
 373    * @return string
 374    */
 375   public function createDocUrl($topic) {
 376     return CRM_Utils_System::getWikiBaseURL() . $topic;
 377   }
 378
 379   /**
 380    * Make a guess about the URL that corresponds to $targetDir.
 381    *
 382    * @param string $targetDir
 383    *   Local path to a directory.
 384    * @return string
 385    *   a guessed URL for $realDir
 386    */
 387   public function guessUrl($targetDir) {
 388     $filePathMarker = $this->getFilePathMarker();
 389     $config = CRM_Core_Config::singleton();
 390
 391     list ($heuristicBaseUrl, $ignore) = explode($filePathMarker, $config->imageUploadURL);
 392     list ($ignore, $heuristicSuffix) = explode($filePathMarker, str_replace('\\', '/', $targetDir));
 393     return $heuristicBaseUrl . $filePathMarker . $heuristicSuffix;
 394   }
 395
 396 }