mod/url/locallib.php

   1 <?php
   2
   3 // This file is part of Moodle - http://moodle.org/
   4 //
   5 // Moodle 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 3 of the License, or
   8 // (at your option) any later version.
   9 //
  10 // Moodle 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
  16 // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  17
  18 /**
  19  * Private url module utility functions
  20  *
  21  * @package    mod_url
  22  * @copyright  2009 Petr Skoda  {@link http://skodak.org}
  23  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  24  */
  25
  26 defined('MOODLE_INTERNAL') || die;
  27
  28 require_once("$CFG->libdir/filelib.php");
  29 require_once("$CFG->libdir/resourcelib.php");
  30 require_once("$CFG->dirroot/mod/url/lib.php");
  31
  32 /**
  33  * This methods does weak url validation, we are looking for major problems only,
  34  * no strict RFE validation.
  35  *
  36  * @param $url
  37  * @return bool true is seems valid, false if definitely not valid URL
  38  */
  39 function url_appears_valid_url($url) {
  40     if (preg_match('/^(\/|https?:|ftp:)/i', $url)) {
  41         // note: this is not exact validation, we look for severely malformed URLs only
  42         return (bool) preg_match('/^[a-z]+:\/\/([^:@\s]+:[^@\s]+@)?[^ @]+(:[0-9]+)?(\/[^#]*)?(#.*)?$/i', $url);
  43     } else {
  44         return (bool)preg_match('/^[a-z]+:\/\/...*$/i', $url);
  45     }
  46 }
  47
  48 /**
  49  * Fix common URL problems that we want teachers to see fixed
  50  * the next time they edit the resource.
  51  *
  52  * This function does not include any XSS protection.
  53  *
  54  * @param string $url
  55  * @return string
  56  */
  57 function url_fix_submitted_url($url) {
  58     // note: empty urls are prevented in form validation
  59     $url = trim($url);
  60
  61     // remove encoded entities - we want the raw URI here
  62     $url = html_entity_decode($url, ENT_QUOTES, 'UTF-8');
  63
  64     if (!preg_match('|^[a-z]+:|i', $url) and !preg_match('|^/|', $url)) {
  65         // invalid URI, try to fix it by making it normal URL,
  66         // please note relative urls are not allowed, /xx/yy links are ok
  67         $url = 'http://'.$url;
  68     }
  69
  70     return $url;
  71 }
  72
  73 /**
  74  * Return full url with all extra parameters
  75  *
  76  * This function does not include any XSS protection.
  77  *
  78  * @param string $url
  79  * @param object $cm
  80  * @param object $course
  81  * @param object $config
  82  * @return string url with & encoded as &amp;
  83  */
  84 function url_get_full_url($url, $cm, $course, $config=null) {
  85
  86     $parameters = empty($url->parameters) ? [] : (array) unserialize_array($url->parameters);
  87
  88     // make sure there are no encoded entities, it is ok to do this twice
  89     $fullurl = html_entity_decode($url->externalurl, ENT_QUOTES, 'UTF-8');
  90
  91     $letters = '\pL';
  92     $latin = 'a-zA-Z';
  93     $digits = '0-9';
  94     $symbols = '\x{20E3}\x{00AE}\x{00A9}\x{203C}\x{2047}\x{2048}\x{2049}\x{3030}\x{303D}\x{2139}\x{2122}\x{3297}\x{3299}' .
  95                '\x{2300}-\x{23FF}\x{2600}-\x{27BF}\x{2B00}-\x{2BF0}';
  96     $arabic = '\x{FE00}-\x{FEFF}';
  97     $math = '\x{2190}-\x{21FF}\x{2900}-\x{297F}';
  98     $othernumbers = '\x{2460}-\x{24FF}';
  99     $geometric = '\x{25A0}-\x{25FF}';
 100     $emojis = '\x{1F000}-\x{1F6FF}';
 101
 102     if (preg_match('/^(\/|https?:|ftp:)/i', $fullurl) or preg_match('|^/|', $fullurl)) {
 103         // encode extra chars in URLs - this does not make it always valid, but it helps with some UTF-8 problems
 104         // Thanks to 💩.la emojis count as valid, too.
 105         $allowed = "[" . $letters . $latin . $digits . $symbols . $arabic . $math . $othernumbers . $geometric .
 106             $emojis . "]" . preg_quote(';/?:@=&$_.+!*(),-#%', '/');
 107         $fullurl = preg_replace_callback("/[^$allowed]/u", 'url_filter_callback', $fullurl);
 108     } else {
 109         // encode special chars only
 110         $fullurl = str_replace('"', '%22', $fullurl);
 111         $fullurl = str_replace('\'', '%27', $fullurl);
 112         $fullurl = str_replace(' ', '%20', $fullurl);
 113         $fullurl = str_replace('<', '%3C', $fullurl);
 114         $fullurl = str_replace('>', '%3E', $fullurl);
 115     }
 116
 117     // add variable url parameters
 118     if (!empty($parameters)) {
 119         if (!$config) {
 120             $config = get_config('url');
 121         }
 122         $paramvalues = url_get_variable_values($url, $cm, $course, $config);
 123
 124         foreach ($parameters as $parse=>$parameter) {
 125             if (isset($paramvalues[$parameter])) {
 126                 $parameters[$parse] = rawurlencode($parse).'='.rawurlencode($paramvalues[$parameter]);
 127             } else {
 128                 unset($parameters[$parse]);
 129             }
 130         }
 131
 132         if (!empty($parameters)) {
 133             if (stripos($fullurl, 'teamspeak://') === 0) {
 134                 $fullurl = $fullurl.'?'.implode('?', $parameters);
 135             } else {
 136                 $join = (strpos($fullurl, '?') === false) ? '?' : '&';
 137                 $fullurl = $fullurl.$join.implode('&', $parameters);
 138             }
 139         }
 140     }
 141
 142     // encode all & to &amp; entity
 143     $fullurl = str_replace('&', '&amp;', $fullurl);
 144
 145     return $fullurl;
 146 }
 147
 148 /**
 149  * Unicode encoding helper callback
 150  * @internal
 151  * @param array $matches
 152  * @return string
 153  */
 154 function url_filter_callback($matches) {
 155     return rawurlencode($matches[0]);
 156 }
 157
 158 /**
 159  * Print url header.
 160  * @param object $url
 161  * @param object $cm
 162  * @param object $course
 163  * @return void
 164  */
 165 function url_print_header($url, $cm, $course) {
 166     global $PAGE, $OUTPUT;
 167
 168     $PAGE->set_title($course->shortname.': '.$url->name);
 169     $PAGE->set_heading($course->fullname);
 170     $PAGE->set_activity_record($url);
 171     echo $OUTPUT->header();
 172 }
 173
 174 /**
 175  * Get url introduction.
 176  *
 177  * @param object $url
 178  * @param object $cm
 179  * @param bool $ignoresettings print even if not specified in modedit
 180  * @return string
 181  */
 182 function url_get_intro(object $url, object $cm, bool $ignoresettings = false): string {
 183     $options = empty($url->displayoptions) ? [] : (array) unserialize_array($url->displayoptions);
 184     if ($ignoresettings or !empty($options['printintro'])) {
 185         if (trim(strip_tags($url->intro))) {
 186             return format_module_intro('url', $url, $cm->id);
 187         }
 188     }
 189
 190     return '';
 191 }
 192
 193 /**
 194  * Display url frames.
 195  * @param object $url
 196  * @param object $cm
 197  * @param object $course
 198  * @return does not return
 199  */
 200 function url_display_frame($url, $cm, $course) {
 201     global $PAGE, $OUTPUT, $CFG;
 202
 203     $frame = optional_param('frameset', 'main', PARAM_ALPHA);
 204
 205     if ($frame === 'top') {
 206         $PAGE->set_pagelayout('frametop');
 207         $PAGE->activityheader->set_attrs([
 208             'description' => url_get_intro($url, $cm),
 209             'title' => format_string($url->name)
 210         ]);
 211         url_print_header($url, $cm, $course);
 212         echo $OUTPUT->footer();
 213         die;
 214
 215     } else {
 216         $config = get_config('url');
 217         $context = context_module::instance($cm->id);
 218         $exteurl = url_get_full_url($url, $cm, $course, $config);
 219         $navurl = "$CFG->wwwroot/mod/url/view.php?id=$cm->id&amp;frameset=top";
 220         $coursecontext = context_course::instance($course->id);
 221         $courseshortname = format_string($course->shortname, true, array('context' => $coursecontext));
 222         $title = strip_tags($courseshortname.': '.format_string($url->name));
 223         $framesize = $config->framesize;
 224         $modulename = s(get_string('modulename','url'));
 225         $contentframetitle = s(format_string($url->name));
 226         $dir = get_string('thisdirection', 'langconfig');
 227
 228         $extframe = <<<EOF
 229 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Frameset//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-frameset.dtd">
 230 <html dir="$dir">
 231   <head>
 232     <meta http-equiv="content-type" content="text/html; charset=utf-8" />
 233     <title>$title</title>
 234   </head>
 235   <frameset rows="$framesize,*">
 236     <frame src="$navurl" title="$modulename"/>
 237     <frame src="$exteurl" title="$contentframetitle"/>
 238   </frameset>
 239 </html>
 240 EOF;
 241
 242         @header('Content-Type: text/html; charset=utf-8');
 243         echo $extframe;
 244         die;
 245     }
 246 }
 247
 248 /**
 249  * Print url info and link.
 250  * @param object $url
 251  * @param object $cm
 252  * @param object $course
 253  * @return does not return
 254  */
 255 function url_print_workaround($url, $cm, $course) {
 256     global $OUTPUT, $PAGE, $USER;
 257
 258     $PAGE->activityheader->set_description(url_get_intro($url, $cm, true));
 259     url_print_header($url, $cm, $course);
 260
 261     $fullurl = url_get_full_url($url, $cm, $course);
 262
 263     $display = url_get_final_display_type($url);
 264     if ($display == RESOURCELIB_DISPLAY_POPUP) {
 265         $jsfullurl = addslashes_js($fullurl);
 266         $options = empty($url->displayoptions) ? [] : (array) unserialize_array($url->displayoptions);
 267         $width  = empty($options['popupwidth'])  ? 620 : $options['popupwidth'];
 268         $height = empty($options['popupheight']) ? 450 : $options['popupheight'];
 269         $wh = "width=$width,height=$height,toolbar=no,location=no,menubar=no,copyhistory=no,status=no,directories=no,scrollbars=yes,resizable=yes";
 270         $extra = "onclick=\"window.open('$jsfullurl', '', '$wh'); return false;\"";
 271
 272     } else if ($display == RESOURCELIB_DISPLAY_NEW) {
 273         $extra = "onclick=\"this.target='_blank';\"";
 274
 275     } else {
 276         $extra = '';
 277     }
 278
 279     echo '<div class="urlworkaround">';
 280     print_string('clicktoopen', 'url', "<a href=\"$fullurl\" $extra>$fullurl</a>");
 281     echo '</div>';
 282
 283     echo $OUTPUT->footer();
 284     die;
 285 }
 286
 287 /**
 288  * Display embedded url file.
 289  * @param object $url
 290  * @param object $cm
 291  * @param object $course
 292  * @return does not return
 293  */
 294 function url_display_embed($url, $cm, $course) {
 295     global $PAGE, $OUTPUT;
 296
 297     $mimetype = resourcelib_guess_url_mimetype($url->externalurl);
 298     $fullurl  = url_get_full_url($url, $cm, $course);
 299     $title    = $url->name;
 300
 301     $link = html_writer::tag('a', $fullurl, array('href'=>str_replace('&amp;', '&', $fullurl)));
 302     $clicktoopen = get_string('clicktoopen', 'url', $link);
 303     $moodleurl = new moodle_url($fullurl);
 304
 305     $extension = resourcelib_get_extension($url->externalurl);
 306
 307     $mediamanager = core_media_manager::instance($PAGE);
 308     $embedoptions = array(
 309         core_media_manager::OPTION_TRUSTED => true,
 310         core_media_manager::OPTION_BLOCK => true
 311     );
 312
 313     if (in_array($mimetype, array('image/gif','image/jpeg','image/png'))) {  // It's an image
 314         $code = resourcelib_embed_image($fullurl, $title);
 315
 316     } else if ($mediamanager->can_embed_url($moodleurl, $embedoptions)) {
 317         // Media (audio/video) file.
 318         $code = $mediamanager->embed_url($moodleurl, $title, 0, 0, $embedoptions);
 319
 320     } else {
 321         // anything else - just try object tag enlarged as much as possible
 322         $code = resourcelib_embed_general($fullurl, $title, $clicktoopen, $mimetype);
 323     }
 324
 325     $PAGE->activityheader->set_description(url_get_intro($url, $cm));
 326     url_print_header($url, $cm, $course);
 327
 328     echo $code;
 329
 330     echo $OUTPUT->footer();
 331     die;
 332 }
 333
 334 /**
 335  * Decide the best display format.
 336  * @param object $url
 337  * @return int display type constant
 338  */
 339 function url_get_final_display_type($url) {
 340     global $CFG;
 341
 342     if ($url->display != RESOURCELIB_DISPLAY_AUTO) {
 343         return $url->display;
 344     }
 345
 346     // detect links to local moodle pages
 347     if (strpos($url->externalurl, $CFG->wwwroot) === 0) {
 348         if (strpos($url->externalurl, 'file.php') === false and strpos($url->externalurl, '.php') !== false ) {
 349             // most probably our moodle page with navigation
 350             return RESOURCELIB_DISPLAY_OPEN;
 351         }
 352     }
 353
 354     // Binaries and other formats that are known to cause trouble for external links.
 355     static $download = ['application/zip', 'application/x-tar', 'application/g-zip',
 356                         'application/pdf', 'text/html', 'document/unknown'];
 357     static $embed    = array('image/gif', 'image/jpeg', 'image/png', 'image/svg+xml',         // images
 358                              'application/x-shockwave-flash', 'video/x-flv', 'video/x-ms-wm', // video formats
 359                              'video/quicktime', 'video/mpeg', 'video/mp4',
 360                              'audio/mp3', 'audio/x-realaudio-plugin', 'x-realaudio-plugin',   // audio formats,
 361                             );
 362
 363     $mimetype = resourcelib_guess_url_mimetype($url->externalurl);
 364
 365     if (in_array($mimetype, $download)) {
 366         return RESOURCELIB_DISPLAY_DOWNLOAD;
 367     }
 368     if (in_array($mimetype, $embed)) {
 369         return RESOURCELIB_DISPLAY_EMBED;
 370     }
 371
 372     // let the browser deal with it somehow
 373     return RESOURCELIB_DISPLAY_OPEN;
 374 }
 375
 376 /**
 377  * Get the parameters that may be appended to URL
 378  * @param object $config url module config options
 379  * @return array array describing opt groups
 380  */
 381 function url_get_variable_options($config) {
 382     global $CFG;
 383
 384     $options = array();
 385     $options[''] = array('' => get_string('chooseavariable', 'url'));
 386
 387     $options[get_string('course')] = array(
 388         'courseid'        => 'id',
 389         'coursefullname'  => get_string('fullnamecourse'),
 390         'courseshortname' => get_string('shortnamecourse'),
 391         'courseidnumber'  => get_string('idnumbercourse'),
 392         'coursesummary'   => get_string('summary'),
 393         'courseformat'    => get_string('format'),
 394     );
 395
 396     $options[get_string('modulename', 'url')] = array(
 397         'urlinstance'     => 'id',
 398         'urlcmid'         => 'cmid',
 399         'urlname'         => get_string('name'),
 400         'urlidnumber'     => get_string('idnumbermod'),
 401     );
 402
 403     $options[get_string('miscellaneous')] = array(
 404         'sitename'        => get_string('fullsitename'),
 405         'serverurl'       => get_string('serverurl', 'url'),
 406         'currenttime'     => get_string('time'),
 407         'lang'            => get_string('language'),
 408     );
 409     if (!empty($config->secretphrase)) {
 410         $options[get_string('miscellaneous')]['encryptedcode'] = get_string('encryptedcode');
 411     }
 412
 413     $options[get_string('user')] = array(
 414         'userid'          => 'id',
 415         'userusername'    => get_string('username'),
 416         'useridnumber'    => get_string('idnumber'),
 417         'userfirstname'   => get_string('firstname'),
 418         'userlastname'    => get_string('lastname'),
 419         'userfullname'    => get_string('fullnameuser'),
 420         'useremail'       => get_string('email'),
 421         'userphone1'      => get_string('phone1'),
 422         'userphone2'      => get_string('phone2'),
 423         'userinstitution' => get_string('institution'),
 424         'userdepartment'  => get_string('department'),
 425         'useraddress'     => get_string('address'),
 426         'usercity'        => get_string('city'),
 427         'usertimezone'    => get_string('timezone'),
 428     );
 429
 430     if ($config->rolesinparams) {
 431         $roles = role_fix_names(get_all_roles());
 432         $roleoptions = array();
 433         foreach ($roles as $role) {
 434             $roleoptions['course'.$role->shortname] = get_string('yourwordforx', '', $role->localname);
 435         }
 436         $options[get_string('roles')] = $roleoptions;
 437     }
 438
 439     return $options;
 440 }
 441
 442 /**
 443  * Get the parameter values that may be appended to URL
 444  * @param object $url module instance
 445  * @param object $cm
 446  * @param object $course
 447  * @param object $config module config options
 448  * @return array of parameter values
 449  */
 450 function url_get_variable_values($url, $cm, $course, $config) {
 451     global $USER, $CFG;
 452
 453     $site = get_site();
 454
 455     $coursecontext = context_course::instance($course->id);
 456
 457     $values = array (
 458         'courseid'        => $course->id,
 459         'coursefullname'  => format_string($course->fullname, true, array('context' => $coursecontext)),
 460         'courseshortname' => format_string($course->shortname, true, array('context' => $coursecontext)),
 461         'courseidnumber'  => $course->idnumber,
 462         'coursesummary'   => $course->summary,
 463         'courseformat'    => $course->format,
 464         'lang'            => current_language(),
 465         'sitename'        => format_string($site->fullname, true, array('context' => $coursecontext)),
 466         'serverurl'       => $CFG->wwwroot,
 467         'currenttime'     => time(),
 468         'urlinstance'     => $url->id,
 469         'urlcmid'         => $cm->id,
 470         'urlname'         => format_string($url->name, true, array('context' => $coursecontext)),
 471         'urlidnumber'     => $cm->idnumber,
 472     );
 473
 474     if (isloggedin()) {
 475         $values['userid']          = $USER->id;
 476         $values['userusername']    = $USER->username;
 477         $values['useridnumber']    = $USER->idnumber;
 478         $values['userfirstname']   = $USER->firstname;
 479         $values['userlastname']    = $USER->lastname;
 480         $values['userfullname']    = fullname($USER);
 481         $values['useremail']       = $USER->email;
 482         $values['userphone1']      = $USER->phone1;
 483         $values['userphone2']      = $USER->phone2;
 484         $values['userinstitution'] = $USER->institution;
 485         $values['userdepartment']  = $USER->department;
 486         $values['useraddress']     = $USER->address;
 487         $values['usercity']        = $USER->city;
 488         $now = new DateTime('now', core_date::get_user_timezone_object());
 489         $values['usertimezone']    = $now->getOffset() / 3600.0; // Value in hours for BC.
 490     }
 491
 492     // weak imitation of Single-Sign-On, for backwards compatibility only
 493     // NOTE: login hack is not included in 2.0 any more, new contrib auth plugin
 494     //       needs to be createed if somebody needs the old functionality!
 495     if (!empty($config->secretphrase)) {
 496         $values['encryptedcode'] = url_get_encrypted_parameter($url, $config);
 497     }
 498
 499     //hmm, this is pretty fragile and slow, why do we need it here??
 500     if ($config->rolesinparams) {
 501         $coursecontext = context_course::instance($course->id);
 502         $roles = role_fix_names(get_all_roles($coursecontext), $coursecontext, ROLENAME_ALIAS);
 503         foreach ($roles as $role) {
 504             $values['course'.$role->shortname] = $role->localname;
 505         }
 506     }
 507
 508     return $values;
 509 }
 510
 511 /**
 512  * BC internal function
 513  * @param object $url
 514  * @param object $config
 515  * @return string
 516  */
 517 function url_get_encrypted_parameter($url, $config) {
 518     global $CFG;
 519
 520     if (file_exists("$CFG->dirroot/local/externserverfile.php")) {
 521         require_once("$CFG->dirroot/local/externserverfile.php");
 522         if (function_exists('extern_server_file')) {
 523             return extern_server_file($url, $config);
 524         }
 525     }
 526     return md5(getremoteaddr().$config->secretphrase);
 527 }
 528
 529 /**
 530  * Optimised mimetype detection from general URL
 531  * @param $fullurl
 532  * @param int $size of the icon.
 533  * @return string|null mimetype or null when the filetype is not relevant.
 534  */
 535 function url_guess_icon($fullurl, $size = null) {
 536     global $CFG;
 537     require_once("$CFG->libdir/filelib.php");
 538
 539     if (substr_count($fullurl, '/') < 3 or substr($fullurl, -1) === '/') {
 540         // Most probably default directory - index.php, index.html, etc. Return null because
 541         // we want to use the default module icon instead of the HTML file icon.
 542         return null;
 543     }
 544
 545     try {
 546         // There can be some cases where the url is invalid making parse_url() to return false.
 547         // That will make moodle_url class to throw an exception, so we need to catch the exception to prevent errors.
 548         $moodleurl = new moodle_url($fullurl);
 549         $fullurl = $moodleurl->out_omit_querystring();
 550     } catch (\moodle_exception $e) {
 551         // If an exception is thrown, means the url is invalid. No need to log exception.
 552         return null;
 553     }
 554
 555     $icon = file_extension_icon($fullurl, $size);
 556     $htmlicon = file_extension_icon('.htm', $size);
 557     $unknownicon = file_extension_icon('', $size);
 558     $phpicon = file_extension_icon('.php', $size); // Exception for php files.
 559
 560     // We do not want to return those icon types, the module icon is more appropriate.
 561     if ($icon === $unknownicon || $icon === $htmlicon || $icon === $phpicon) {
 562         return null;
 563     }
 564
 565     return $icon;
 566 }