lib/tests/htmlpurifier_test.php

   1 <?php
   2 // This file is part of Moodle - http://moodle.org/
   3 //
   4 // Moodle is free software: you can redistribute it and/or modify
   5 // it under the terms of the GNU General Public License as published by
   6 // the Free Software Foundation, either version 3 of the License, or
   7 // (at your option) any later version.
   8 //
   9 // Moodle is distributed in the hope that it will be useful,
  10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 // GNU General Public License for more details.
  13 //
  14 // You should have received a copy of the GNU General Public License
  15 // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  16
  17 /**
  18  * Unit tests for the HTMLPurifier integration
  19  *
  20  * @package    core
  21  * @category   phpunit
  22  * @copyright  2012 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
  29 /**
  30  * HTMLPurifier test case
  31  *
  32  * @package    core
  33  * @category   phpunit
  34  * @copyright  2012 Petr Skoda {@link http://skodak.org}
  35  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  36  */
  37 class core_htmlpurifier_testcase extends basic_testcase {
  38
  39     /**
  40      * Verify _blank target is allowed.
  41      */
  42     public function test_allow_blank_target() {
  43         // See MDL-52651 for an explanation as to why the rel="noreferrer" attribute is expected here.
  44         // Also note we do not need to test links with an existing rel attribute as the HTML Purifier is configured to remove
  45         // the rel attribute.
  46         $text = '<a href="http://moodle.org" target="_blank">Some link</a>';
  47         $expected = '<a href="http://moodle.org" target="_blank" rel="noreferrer noopener">Some link</a>';
  48         $result = format_text($text, FORMAT_HTML);
  49         $this->assertSame($expected, $result);
  50
  51         $result = format_text('<a href="http://moodle.org" target="some">Some link</a>', FORMAT_HTML);
  52         $this->assertSame('<a href="http://moodle.org">Some link</a>', $result);
  53     }
  54
  55     /**
  56      * Verify our nolink tag accepted.
  57      */
  58     public function test_nolink() {
  59         // We can not use format text because nolink changes result.
  60         $text = '<nolink><div>no filters</div></nolink>';
  61         $result = purify_html($text, array());
  62         $this->assertSame($text, $result);
  63
  64         $text = '<nolink>xxx<em>xx</em><div>xxx</div></nolink>';
  65         $result = purify_html($text, array());
  66         $this->assertSame($text, $result);
  67     }
  68
  69     /**
  70      * Verify our tex tag accepted.
  71      */
  72     public function test_tex() {
  73         $text = '<tex>a+b=c</tex>';
  74         $result = purify_html($text, array());
  75         $this->assertSame($text, $result);
  76     }
  77
  78     /**
  79      * Verify our algebra tag accepted.
  80      */
  81     public function test_algebra() {
  82         $text = '<algebra>a+b=c</algebra>';
  83         $result = purify_html($text, array());
  84         $this->assertSame($text, $result);
  85     }
  86
  87     /**
  88      * Verify our hacky multilang works.
  89      */
  90     public function test_multilang() {
  91         $text = '<lang lang="en">hmmm</lang><lang lang="anything">hm</lang>';
  92         $result = purify_html($text, array());
  93         $this->assertSame($text, $result);
  94
  95         $text = '<span lang="en" class="multilang">hmmm</span><span lang="anything" class="multilang">hm</span>';
  96         $result = purify_html($text, array());
  97         $this->assertSame($text, $result);
  98
  99         $text = '<span lang="en">hmmm</span>';
 100         $result = purify_html($text, array());
 101         $this->assertNotSame($text, $result);
 102
 103         // Keep standard lang tags.
 104
 105         $text = '<span lang="de_DU" class="multilang">asas</span>';
 106         $result = purify_html($text, array());
 107         $this->assertSame($text, $result);
 108
 109         $text = '<lang lang="de_DU">xxxxxx</lang>';
 110         $result = purify_html($text, array());
 111         $this->assertSame($text, $result);
 112     }
 113
 114     /**
 115      * Tests the 'allowid' option for format_text.
 116      */
 117     public function test_format_text_allowid() {
 118         // Start off by not allowing ids (default).
 119         $options = array(
 120             'nocache' => true
 121         );
 122         $result = format_text('<div id="example">Frog</div>', FORMAT_HTML, $options);
 123         $this->assertSame('<div>Frog</div>', $result);
 124
 125         // Now allow ids.
 126         $options['allowid'] = true;
 127         $result = format_text('<div id="example">Frog</div>', FORMAT_HTML, $options);
 128         $this->assertSame('<div id="example">Frog</div>', $result);
 129     }
 130
 131     public function test_allowobjectembed() {
 132         global $CFG;
 133
 134         $this->assertSame('0', $CFG->allowobjectembed);
 135
 136         $text = '<object width="425" height="350">
 137 <param name="movie" value="http://www.youtube.com/v/AyPzM5WK8ys" />
 138 <param name="wmode" value="transparent" />
 139 <embed src="http://www.youtube.com/v/AyPzM5WK8ys" type="application/x-shockwave-flash" wmode="transparent" width="425" height="350" />
 140 </object>hmmm';
 141         $result = purify_html($text, array());
 142         $this->assertSame('hmmm', trim($result));
 143
 144         $CFG->allowobjectembed = '1';
 145
 146         $expected = '<object width="425" height="350" data="http://www.youtube.com/v/AyPzM5WK8ys" type="application/x-shockwave-flash">
 147 <param name="allowScriptAccess" value="never" />
 148 <param name="allowNetworking" value="internal" />
 149 <param name="movie" value="http://www.youtube.com/v/AyPzM5WK8ys" />
 150 <param name="wmode" value="transparent" />
 151 <embed src="http://www.youtube.com/v/AyPzM5WK8ys" type="application/x-shockwave-flash" wmode="transparent" width="425" height="350" allowscriptaccess="never" allownetworking="internal" />
 152 </object>hmmm';
 153         $result = purify_html($text, array());
 154         $this->assertSame(str_replace("\n", '', $expected), str_replace("\n", '', $result));
 155
 156         $CFG->allowobjectembed = '0';
 157
 158         $result = purify_html($text, array());
 159         $this->assertSame('hmmm', trim($result));
 160     }
 161
 162     /**
 163      * Test if linebreaks kept unchanged.
 164      */
 165     public function test_line_breaking() {
 166         $text = "\n\raa\rsss\nsss\r";
 167         $this->assertSame($text, purify_html($text));
 168     }
 169
 170     /**
 171      * Test fixing of strict problems.
 172      */
 173     public function test_tidy() {
 174         $text = "<p>xx";
 175         $this->assertSame('<p>xx</p>', purify_html($text));
 176
 177         $text = "<P>xx</P>";
 178         $this->assertSame('<p>xx</p>', purify_html($text));
 179
 180         $text = "xx<br>";
 181         $this->assertSame('xx<br />', purify_html($text));
 182     }
 183
 184     /**
 185      * Test nesting - this used to cause problems in earlier versions.
 186      */
 187     public function test_nested_lists() {
 188         $text = "<ul><li>One<ul><li>Two</li></ul></li><li>Three</li></ul>";
 189         $this->assertSame($text, purify_html($text));
 190     }
 191
 192     /**
 193      * Test that XSS protection works, complete smoke tests are in htmlpurifier itself.
 194      */
 195     public function test_cleaning_nastiness() {
 196         $text = "x<SCRIPT>alert('XSS')</SCRIPT>x";
 197         $this->assertSame('xx', purify_html($text));
 198
 199         $text = '<DIV STYLE="background-image:url(javascript:alert(\'XSS\'))">xx</DIV>';
 200         $this->assertSame('<div>xx</div>', purify_html($text));
 201
 202         $text = '<DIV STYLE="width:expression(alert(\'XSS\'));">xx</DIV>';
 203         $this->assertSame('<div>xx</div>', purify_html($text));
 204
 205         $text = 'x<IFRAME SRC="javascript:alert(\'XSS\');"></IFRAME>x';
 206         $this->assertSame('xx', purify_html($text));
 207
 208         $text = 'x<OBJECT TYPE="text/x-scriptlet" DATA="http://ha.ckers.org/scriptlet.html"></OBJECT>x';
 209         $this->assertSame('xx', purify_html($text));
 210
 211         $text = 'x<EMBED SRC="http://ha.ckers.org/xss.swf" AllowScriptAccess="always"></EMBED>x';
 212         $this->assertSame('xx', purify_html($text));
 213
 214         $text = 'x<form></form>x';
 215         $this->assertSame('xx', purify_html($text));
 216     }
 217
 218     /**
 219      * Test internal function used for clean_text() speedup.
 220      */
 221     public function test_is_purify_html_necessary() {
 222         // First our shortcuts.
 223         $text = "";
 224         $this->assertFalse(is_purify_html_necessary($text));
 225         $this->assertSame($text, purify_html($text));
 226
 227         $text = "666";
 228         $this->assertFalse(is_purify_html_necessary($text));
 229         $this->assertSame($text, purify_html($text));
 230
 231         $text = "abc\ndef \" ' ";
 232         $this->assertFalse(is_purify_html_necessary($text));
 233         $this->assertSame($text, purify_html($text));
 234
 235         $text = "abc\n<p>def</p>efg<p>hij</p>";
 236         $this->assertFalse(is_purify_html_necessary($text));
 237         $this->assertSame($text, purify_html($text));
 238
 239         $text = "<br />abc\n<p>def<em>efg</em><strong>hi<br />j</strong></p>";
 240         $this->assertFalse(is_purify_html_necessary($text));
 241         $this->assertSame($text, purify_html($text));
 242
 243         // Now failures.
 244         $text = "&nbsp;";
 245         $this->assertTrue(is_purify_html_necessary($text));
 246
 247         $text = "Gin & Tonic";
 248         $this->assertTrue(is_purify_html_necessary($text));
 249
 250         $text = "Gin > Tonic";
 251         $this->assertTrue(is_purify_html_necessary($text));
 252
 253         $text = "Gin < Tonic";
 254         $this->assertTrue(is_purify_html_necessary($text));
 255
 256         $text = "<div>abc</div>";
 257         $this->assertTrue(is_purify_html_necessary($text));
 258
 259         $text = "<span>abc</span>";
 260         $this->assertTrue(is_purify_html_necessary($text));
 261
 262         $text = "<br>abc";
 263         $this->assertTrue(is_purify_html_necessary($text));
 264
 265         $text = "<p class='xxx'>abc</p>";
 266         $this->assertTrue(is_purify_html_necessary($text));
 267
 268         $text = "<p>abc<em></p></em>";
 269         $this->assertTrue(is_purify_html_necessary($text));
 270
 271         $text = "<p>abc";
 272         $this->assertTrue(is_purify_html_necessary($text));
 273     }
 274
 275     public function test_allowed_schemes() {
 276         // First standard schemas.
 277         $text = '<a href="http://www.example.com/course/view.php?id=5">link</a>';
 278         $this->assertSame($text, purify_html($text));
 279
 280         $text = '<a href="https://www.example.com/course/view.php?id=5">link</a>';
 281         $this->assertSame($text, purify_html($text));
 282
 283         $text = '<a href="ftp://user@ftp.example.com/some/file.txt">link</a>';
 284         $this->assertSame($text, purify_html($text));
 285
 286         $text = '<a href="nntp://example.com/group/123">link</a>';
 287         $this->assertSame($text, purify_html($text));
 288
 289         $text = '<a href="news:groupname">link</a>';
 290         $this->assertSame($text, purify_html($text));
 291
 292         $text = '<a href="mailto:user@example.com">link</a>';
 293         $this->assertSame($text, purify_html($text));
 294
 295         // Extra schemes allowed in moodle.
 296         $text = '<a href="irc://irc.example.com/3213?pass">link</a>';
 297         $this->assertSame($text, purify_html($text));
 298
 299         $text = '<a href="rtsp://www.example.com/movie.mov">link</a>';
 300         $this->assertSame($text, purify_html($text));
 301
 302         $text = '<a href="rtmp://www.example.com/video.f4v">link</a>';
 303         $this->assertSame($text, purify_html($text));
 304
 305         $text = '<a href="teamspeak://speak.example.com/?par=val?par2=val2">link</a>';
 306         $this->assertSame($text, purify_html($text));
 307
 308         $text = '<a href="gopher://gopher.example.com/resource">link</a>';
 309         $this->assertSame($text, purify_html($text));
 310
 311         $text = '<a href="mms://www.example.com/movie.mms">link</a>';
 312         $this->assertSame($text, purify_html($text));
 313
 314         // Now some borked or dangerous schemes.
 315         $text = '<a href="javascript://www.example.com">link</a>';
 316         $this->assertSame('<a>link</a>', purify_html($text));
 317
 318         $text = '<a href="hmmm://www.example.com">link</a>';
 319         $this->assertSame('<a>link</a>', purify_html($text));
 320     }
 321
 322     /**
 323      * Test non-ascii domain names
 324      */
 325     public function test_idn() {
 326
 327         // Example of domain that gives the same result in IDNA2003 and IDNA2008 .
 328         $text = '<a href="http://правительство.рф">правительство.рф</a>';
 329         $expected = '<a href="http://xn--80aealotwbjpid2k.xn--p1ai">правительство.рф</a>';
 330         $this->assertSame($expected, purify_html($text));
 331
 332         // Examples of deviations from http://www.unicode.org/reports/tr46/#Table_Deviation_Characters .
 333         $text = '<a href="http://teßt.de">teßt.de</a>';
 334         $expected = '<a href="http://xn--tet-6ka.de">teßt.de</a>';
 335         $this->assertSame($expected, purify_html($text));
 336
 337         $text = '<a href="http://βόλος.com">http://βόλος.com</a>';
 338         $expected = '<a href="http://xn--nxasmm1c.com">http://βόλος.com</a>';
 339         $this->assertSame($expected, purify_html($text));
 340
 341         $text = '<a href="http://نامه‌ای.com">http://نامه‌ای.com</a>';
 342         $expected = '<a href="http://xn--mgba3gch31f060k.com">http://نامه‌ای.com</a>';
 343         $this->assertSame($expected, purify_html($text));
 344     }
 345
 346     /**
 347      * Tests media tags.
 348      *
 349      * @dataProvider media_tags_provider
 350      * @param string $mediatag HTML media tag
 351      * @param string $expected expected result
 352      */
 353     public function test_media_tags($mediatag, $expected) {
 354         $actual = format_text($mediatag, FORMAT_MOODLE, ['filter' => false]);
 355         $this->assertEquals($expected, $actual);
 356     }
 357
 358     /**
 359      * Test cases for the test_media_tags test.
 360      */
 361     public function media_tags_provider() {
 362         // Takes an array of attributes, then generates a test for each of them.
 363         $generatetestcases = function($prefix, array $attrs, array $templates) {
 364             return array_reduce($attrs, function($carry, $attr) use ($prefix, $templates) {
 365                 $testcase = [$prefix . '/' . $attr => [
 366                     sprintf($templates[0], $attr),
 367                     sprintf($templates[1], $attr)
 368                 ]];
 369                 return empty(array_values($carry)[0]) ? $testcase : $carry + $testcase;
 370             }, [[]]);
 371         };
 372
 373         $audioattrs = [
 374             'preload="auto"', 'autoplay=""', 'loop=""', 'muted=""', 'controls=""',
 375             'crossorigin="anonymous"', 'crossorigin="use-credentials"'
 376         ];
 377         $videoattrs = [
 378             'crossorigin="anonymous"', 'crossorigin="use-credentials"',
 379             'poster="https://upload.wikimedia.org/wikipedia/en/1/14/Space_jam.jpg"',
 380             'preload="auto"', 'autoplay=""', 'playsinline=""', 'loop=""', 'muted=""',
 381             'controls=""', 'width="420"', 'height="69"'
 382         ];
 383         return $generatetestcases('Plain audio', $audioattrs + ['src="http://example.com/jam.wav"'], [
 384                 '<audio %1$s>Looks like you can\'t slam the jams.</audio>',
 385                 '<div class="text_to_html"><audio %1$s>Looks like you can\'t slam the jams.</audio></div>'
 386             ]) + $generatetestcases('Audio with one source', $audioattrs, [
 387                 '<audio %1$s><source src="http://example.com/getup.wav">No tasty jams for you.</audio>',
 388                 '<div class="text_to_html">' .
 389                     '<audio %1$s>' .
 390                         '<source src="http://example.com/getup.wav" />' .
 391                         'No tasty jams for you.' .
 392                     '</audio>' .
 393                 '</div>'
 394             ]) + $generatetestcases('Audio with multiple sources', $audioattrs, [
 395                 '<audio %1$s>' .
 396                     '<source src="http://example.com/getup.wav" type="audio/wav">' .
 397                     '<source src="http://example.com/getup.mp3" type="audio/mpeg">' .
 398                     '<source src="http://example.com/getup.ogg" type="audio/ogg">' .
 399                     'No tasty jams for you.' .
 400                 '</audio>',
 401                 '<div class="text_to_html">' .
 402                     '<audio %1$s>' .
 403                         '<source src="http://example.com/getup.wav" type="audio/wav" />' .
 404                         '<source src="http://example.com/getup.mp3" type="audio/mpeg" />' .
 405                         '<source src="http://example.com/getup.ogg" type="audio/ogg" />' .
 406                         'No tasty jams for you.' .
 407                     '</audio>' .
 408                 '</div>'
 409             ]) + $generatetestcases('Audio with sources and tracks', $audioattrs, [
 410                 '<audio %1$s>' .
 411                     '<source src="http://example.com/getup.wav" type="audio/wav">' .
 412                     '<track kind="subtitles" src="http://example.com/subtitles_en.vtt" label="English" srclang="en">' .
 413                     '<track kind="subtitles" src="http://example.com/subtitles_es.vtt" label="Espanol" srclang="es">' .
 414                     'No tasty jams for you.' .
 415                 '</audio>',
 416                 '<div class="text_to_html">' .
 417                     '<audio %1$s>' .
 418                         '<source src="http://example.com/getup.wav" type="audio/wav" />' .
 419                         '<track kind="subtitles" src="http://example.com/subtitles_en.vtt" label="English" srclang="en" />' .
 420                         '<track kind="subtitles" src="http://example.com/subtitles_es.vtt" label="Espanol" srclang="es" />' .
 421                         'No tasty jams for you.' .
 422                     '</audio>' .
 423                 '</div>'
 424             ]) + $generatetestcases('Plain video', $videoattrs + ['src="http://example.com/prettygood.mp4'], [
 425                 '<video %1$s>Oh, that\'s pretty bad 😦</video>',
 426                 '<div class="text_to_html"><video %1$s>Oh, that\'s pretty bad 😦</video></div>'
 427             ]) + $generatetestcases('Video with illegal subtag', $videoattrs + ['src="http://example.com/prettygood.mp4'], [
 428                 '<video %1$s><subtag></subtag>Oh, that\'s pretty bad 😦</video>',
 429                 '<div class="text_to_html"><video %1$s>Oh, that\'s pretty bad 😦</video></div>'
 430             ]) + $generatetestcases('Video with legal subtag', $videoattrs + ['src="http://example.com/prettygood.mp4'], [
 431                 '<video %1$s>Did not work <a href="http://example.com/prettygood.mp4">click here to download</a></video>',
 432                 '<div class="text_to_html"><video %1$s>Did not work <a href="http://example.com/prettygood.mp4">' .
 433                 'click here to download</a></video></div>'
 434             ]) + $generatetestcases('Source tag without video or audio', $videoattrs, [
 435                 'some text <source src="http://example.com/getup.wav" type="audio/wav"> the end',
 436                 '<div class="text_to_html">some text  the end</div>'
 437             ]) + $generatetestcases('Video with one source', $videoattrs, [
 438                 '<video %1$s><source src="http://example.com/prettygood.mp4">Oh, that\'s pretty bad 😦</video>',
 439                 '<div class="text_to_html">' .
 440                     '<video %1$s>' .
 441                         '<source src="http://example.com/prettygood.mp4" />' .
 442                         'Oh, that\'s pretty bad 😦' .
 443                     '</video>' .
 444                 '</div>'
 445             ]) + $generatetestcases('Video with multiple sources', $videoattrs, [
 446                 '<video %1$s>' .
 447                     '<source src="http://example.com/prettygood.mp4" type="video/mp4">' .
 448                     '<source src="http://example.com/eljefe.mp4" type="video/mp4">' .
 449                     '<source src="http://example.com/turnitup.mov" type="video/mov">' .
 450                     'Oh, that\'s pretty bad 😦' .
 451                 '</video>',
 452                 '<div class="text_to_html">' .
 453                     '<video %1$s>' .
 454                         '<source src="http://example.com/prettygood.mp4" type="video/mp4" />' .
 455                         '<source src="http://example.com/eljefe.mp4" type="video/mp4" />' .
 456                         '<source src="http://example.com/turnitup.mov" type="video/mov" />' .
 457                         'Oh, that\'s pretty bad 😦' .
 458                     '</video>' .
 459                 '</div>'
 460             ]) + $generatetestcases('Video with sources and tracks', $audioattrs, [
 461                 '<video %1$s>' .
 462                     '<source src="http://example.com/getup.wav" type="audio/wav">' .
 463                     '<track kind="subtitles" src="http://example.com/subtitles_en.vtt" label="English" srclang="en">' .
 464                     '<track kind="subtitles" src="http://example.com/subtitles_es.vtt" label="Espanol" srclang="es">' .
 465                     'No tasty jams for you.' .
 466                 '</video>',
 467                 '<div class="text_to_html">' .
 468                     '<video %1$s>' .
 469                         '<source src="http://example.com/getup.wav" type="audio/wav" />' .
 470                         '<track kind="subtitles" src="http://example.com/subtitles_en.vtt" label="English" srclang="en" />' .
 471                         '<track kind="subtitles" src="http://example.com/subtitles_es.vtt" label="Espanol" srclang="es" />' .
 472                     'No tasty jams for you.' .
 473                     '</video>' .
 474                 '</div>'
 475             ]) + ['Video with invalid crossorigin' => [
 476                     '<video src="http://example.com/turnitup.mov" crossorigin="can i pls hab?">' .
 477                         'Oh, that\'s pretty bad 😦' .
 478                     '</video>',
 479                     '<div class="text_to_html">' .
 480                         '<video src="http://example.com/turnitup.mov">' .
 481                            'Oh, that\'s pretty bad 😦' .
 482                         '</video>' .
 483                     '</div>'
 484             ]] + ['Audio with invalid crossorigin' => [
 485                     '<audio src="http://example.com/getup.wav" crossorigin="give me. the jams.">' .
 486                         'nyemnyemnyem' .
 487                     '</audio>',
 488                     '<div class="text_to_html">' .
 489                         '<audio src="http://example.com/getup.wav">' .
 490                             'nyemnyemnyem' .
 491                         '</audio>' .
 492                     '</div>'
 493             ]] + ['Other attributes' => [
 494                 '<video src="http://example.com/turnitdown.mov" class="nofilter" data-something="data attribute" someattribute="somevalue" onclick="boom">' .
 495                     '<source src="http://example.com/getup.wav" type="audio/wav" class="shouldberemoved" data-sourcedata="source data" onmouseover="kill session" />' .
 496                     '<track src="http://example.com/subtitles_en.vtt" class="shouldberemoved" data-trackdata="track data" onmouseover="removeme" />' .
 497                     'Do not remove attribute class but remove other attributes' .
 498                 '</video>',
 499                 '<div class="text_to_html">' .
 500                     '<video src="http://example.com/turnitdown.mov" class="nofilter">' .
 501                         '<source src="http://example.com/getup.wav" type="audio/wav" />' .
 502                         '<track src="http://example.com/subtitles_en.vtt" />' .
 503                         'Do not remove attribute class but remove other attributes' .
 504                     '</video>' .
 505                 '</div>'
 506             ]];
 507     }
 508 }