| [ Index ] |
PHP Cross Reference of WordPress Trunk (Updated Daily) |
[Summary view] [Print] [Text view]
1 <?php 2 /** 3 * kses 0.2.2 - HTML/XHTML filter that only allows some elements and attributes 4 * Copyright (C) 2002, 2003, 2005 Ulf Harnhammar 5 * 6 * This program is free software and open source software; you can redistribute 7 * it and/or modify it under the terms of the GNU General Public License as 8 * published by the Free Software Foundation; either version 2 of the License, 9 * or (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 14 * more details. 15 * 16 * You should have received a copy of the GNU General Public License along 17 * with this program; if not, write to the Free Software Foundation, Inc., 18 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA 19 * http://www.gnu.org/licenses/gpl.html 20 * 21 * [kses strips evil scripts!] 22 * 23 * Added wp_ prefix to avoid conflicts with existing kses users 24 * 25 * @version 0.2.2 26 * @copyright (C) 2002, 2003, 2005 27 * @author Ulf Harnhammar <http://advogato.org/person/metaur/> 28 * 29 * @package External 30 * @subpackage KSES 31 */ 32 33 /** 34 * Specifies the default allowable HTML tags. 35 * 36 * Using `CUSTOM_TAGS` is not recommended and should be considered deprecated. The 37 * {@see 'wp_kses_allowed_html'} filter is more powerful and supplies context. 38 * 39 * When using this constant, make sure to set all of these globals to arrays: 40 * 41 * - `$allowedposttags` 42 * - `$allowedtags` 43 * - `$allowedentitynames` 44 * - `$allowedxmlentitynames` 45 * 46 * @see wp_kses_allowed_html() 47 * @since 1.2.0 48 * 49 * @var array[]|false Array of default allowable HTML tags, or false to use the defaults. 50 */ 51 if ( ! defined( 'CUSTOM_TAGS' ) ) { 52 define( 'CUSTOM_TAGS', false ); 53 } 54 55 // Ensure that these variables are added to the global namespace 56 // (e.g. if using namespaces / autoload in the current PHP environment). 57 global $allowedposttags, $allowedtags, $allowedentitynames, $allowedxmlentitynames; 58 59 if ( ! CUSTOM_TAGS ) { 60 /** 61 * KSES global for default allowable HTML tags. 62 * 63 * Can be overridden with the `CUSTOM_TAGS` constant. 64 * 65 * @var array[] $allowedposttags Array of default allowable HTML tags. 66 * @since 2.0.0 67 */ 68 $allowedposttags = array( 69 'address' => array(), 70 'a' => array( 71 'href' => true, 72 'rel' => true, 73 'rev' => true, 74 'name' => true, 75 'target' => true, 76 'download' => array( 77 'valueless' => 'y', 78 ), 79 ), 80 'abbr' => array(), 81 'acronym' => array(), 82 'area' => array( 83 'alt' => true, 84 'coords' => true, 85 'href' => true, 86 'nohref' => true, 87 'shape' => true, 88 'target' => true, 89 ), 90 'article' => array( 91 'align' => true, 92 ), 93 'aside' => array( 94 'align' => true, 95 ), 96 'audio' => array( 97 'autoplay' => true, 98 'controls' => true, 99 'loop' => true, 100 'muted' => true, 101 'preload' => true, 102 'src' => true, 103 ), 104 'b' => array(), 105 'bdo' => array(), 106 'big' => array(), 107 'blockquote' => array( 108 'cite' => true, 109 ), 110 'br' => array(), 111 'button' => array( 112 'command' => true, 113 'commandfor' => true, 114 'disabled' => true, 115 'name' => true, 116 'type' => true, 117 'value' => true, 118 'popovertarget' => true, 119 'popovertargetaction' => true, 120 'aria-haspopup' => true, 121 ), 122 'caption' => array( 123 'align' => true, 124 ), 125 'cite' => array(), 126 'code' => array(), 127 'col' => array( 128 'align' => true, 129 'char' => true, 130 'charoff' => true, 131 'span' => true, 132 'valign' => true, 133 'width' => true, 134 ), 135 'colgroup' => array( 136 'align' => true, 137 'char' => true, 138 'charoff' => true, 139 'span' => true, 140 'valign' => true, 141 'width' => true, 142 ), 143 'data' => array( 144 'value' => true, 145 ), 146 'del' => array( 147 'datetime' => true, 148 ), 149 'dd' => array(), 150 'dfn' => array(), 151 'details' => array( 152 'align' => true, 153 'open' => true, 154 'name' => true, 155 ), 156 'div' => array( 157 'align' => true, 158 'popover' => true, 159 ), 160 'dialog' => array( 161 'closedby' => true, 162 'open' => true, 163 'popover' => true, 164 'autofocus' => true, 165 ), 166 'dl' => array(), 167 'dt' => array(), 168 'em' => array(), 169 'fieldset' => array(), 170 'figure' => array( 171 'align' => true, 172 ), 173 'figcaption' => array( 174 'align' => true, 175 ), 176 'font' => array( 177 'color' => true, 178 'face' => true, 179 'size' => true, 180 ), 181 'footer' => array( 182 'align' => true, 183 ), 184 'h1' => array( 185 'align' => true, 186 ), 187 'h2' => array( 188 'align' => true, 189 ), 190 'h3' => array( 191 'align' => true, 192 ), 193 'h4' => array( 194 'align' => true, 195 ), 196 'h5' => array( 197 'align' => true, 198 ), 199 'h6' => array( 200 'align' => true, 201 ), 202 'header' => array( 203 'align' => true, 204 ), 205 'hgroup' => array( 206 'align' => true, 207 ), 208 'hr' => array( 209 'align' => true, 210 'noshade' => true, 211 'size' => true, 212 'width' => true, 213 ), 214 'i' => array(), 215 'img' => array( 216 'alt' => true, 217 'align' => true, 218 'border' => true, 219 'height' => true, 220 'hspace' => true, 221 'loading' => true, 222 'longdesc' => true, 223 'vspace' => true, 224 'src' => true, 225 'usemap' => true, 226 'width' => true, 227 ), 228 'ins' => array( 229 'datetime' => true, 230 'cite' => true, 231 ), 232 'kbd' => array(), 233 'label' => array( 234 'for' => true, 235 ), 236 'legend' => array( 237 'align' => true, 238 ), 239 'li' => array( 240 'align' => true, 241 'value' => true, 242 ), 243 'main' => array( 244 'align' => true, 245 ), 246 'map' => array( 247 'name' => true, 248 ), 249 'mark' => array(), 250 'menu' => array( 251 'type' => true, 252 ), 253 'meter' => array( 254 'high' => true, 255 'low' => true, 256 'max' => true, 257 'min' => true, 258 'optimum' => true, 259 'value' => true, 260 ), 261 'nav' => array( 262 'align' => true, 263 ), 264 'object' => array( 265 'data' => array( 266 'required' => true, 267 'value_callback' => '_wp_kses_allow_pdf_objects', 268 ), 269 'type' => array( 270 'required' => true, 271 'values' => array( 'application/pdf' ), 272 ), 273 ), 274 'p' => array( 275 'align' => true, 276 ), 277 'pre' => array( 278 'width' => true, 279 ), 280 'progress' => array( 281 'max' => true, 282 'value' => true, 283 ), 284 'q' => array( 285 'cite' => true, 286 ), 287 'rb' => array(), 288 'rp' => array(), 289 'rt' => array(), 290 'rtc' => array(), 291 'ruby' => array(), 292 's' => array(), 293 'samp' => array(), 294 'search' => array(), 295 'span' => array( 296 'align' => true, 297 ), 298 'section' => array( 299 'align' => true, 300 ), 301 'small' => array(), 302 'strike' => array(), 303 'strong' => array(), 304 'sub' => array(), 305 'summary' => array( 306 'align' => true, 307 ), 308 'sup' => array(), 309 'table' => array( 310 'align' => true, 311 'bgcolor' => true, 312 'border' => true, 313 'cellpadding' => true, 314 'cellspacing' => true, 315 'rules' => true, 316 'summary' => true, 317 'width' => true, 318 ), 319 'tbody' => array( 320 'align' => true, 321 'char' => true, 322 'charoff' => true, 323 'valign' => true, 324 ), 325 'td' => array( 326 'abbr' => true, 327 'align' => true, 328 'axis' => true, 329 'bgcolor' => true, 330 'char' => true, 331 'charoff' => true, 332 'colspan' => true, 333 'headers' => true, 334 'height' => true, 335 'nowrap' => true, 336 'rowspan' => true, 337 'scope' => true, 338 'valign' => true, 339 'width' => true, 340 ), 341 'textarea' => array( 342 'cols' => true, 343 'rows' => true, 344 'disabled' => true, 345 'name' => true, 346 'readonly' => true, 347 ), 348 'tfoot' => array( 349 'align' => true, 350 'char' => true, 351 'charoff' => true, 352 'valign' => true, 353 ), 354 'th' => array( 355 'abbr' => true, 356 'align' => true, 357 'axis' => true, 358 'bgcolor' => true, 359 'char' => true, 360 'charoff' => true, 361 'colspan' => true, 362 'headers' => true, 363 'height' => true, 364 'nowrap' => true, 365 'rowspan' => true, 366 'scope' => true, 367 'valign' => true, 368 'width' => true, 369 ), 370 'thead' => array( 371 'align' => true, 372 'char' => true, 373 'charoff' => true, 374 'valign' => true, 375 ), 376 'time' => array( 377 'datetime' => true, 378 ), 379 'title' => array(), 380 'tr' => array( 381 'align' => true, 382 'bgcolor' => true, 383 'char' => true, 384 'charoff' => true, 385 'valign' => true, 386 ), 387 'track' => array( 388 'default' => true, 389 'kind' => true, 390 'label' => true, 391 'src' => true, 392 'srclang' => true, 393 ), 394 'tt' => array(), 395 'u' => array(), 396 'ul' => array( 397 'type' => true, 398 'popover' => true, 399 'role' => true, 400 ), 401 'ol' => array( 402 'start' => true, 403 'type' => true, 404 'reversed' => true, 405 ), 406 'var' => array(), 407 'video' => array( 408 'autoplay' => true, 409 'controls' => true, 410 'height' => true, 411 'loop' => true, 412 'muted' => true, 413 'playsinline' => true, 414 'poster' => true, 415 'preload' => true, 416 'src' => true, 417 'width' => true, 418 ), 419 'wbr' => array(), 420 ); 421 422 // https://www.w3.org/TR/mathml-core/#global-attributes 423 // Except common attributes added by _wp_add_global_attributes. 424 $math_global_attributes = array( 425 'displaystyle' => true, 426 'scriptlevel' => true, 427 'mathbackground' => true, 428 'mathcolor' => true, 429 'mathsize' => true, 430 // Common attributes also defined by _wp_add_global_attributes. 431 // We do not want to add all those global attributes though. 432 'class' => true, 433 'data-*' => true, 434 'dir' => true, 435 'id' => true, 436 'style' => true, 437 ); 438 439 $math_overunder_attributes = array( 440 'accentunder' => true, 441 'accent' => true, 442 ); 443 444 $allowedposttags = array_merge( 445 $allowedposttags, 446 array( 447 // https://www.w3.org/TR/mathml-core/#the-top-level-math-element 448 'math' => array_merge( 449 $math_global_attributes, 450 array( 451 'display' => true, 452 ) 453 ), 454 455 // https://www.w3.org/TR/mathml-core/#token-elements 456 // https://www.w3.org/TR/mathml-core/#text-mtext 457 'mtext' => $math_global_attributes, 458 // https://www.w3.org/TR/mathml-core/#the-mi-element 459 'mi' => array_merge( 460 $math_global_attributes, 461 array( 462 'mathvariant' => true, 463 ) 464 ), 465 // https://www.w3.org/TR/mathml-core/#number-mn 466 'mn' => $math_global_attributes, 467 // https://www.w3.org/TR/mathml-core/#operator-fence-separator-or-accent-mo 468 'mo' => array_merge( 469 $math_global_attributes, 470 array( 471 'form' => true, 472 'fence' => true, 473 'separator' => true, 474 'lspace' => true, 475 'rspace' => true, 476 'stretchy' => true, 477 'symmetric' => true, 478 'maxsize' => true, 479 'minsize' => true, 480 'largeop' => true, 481 'movablelimits' => true, 482 ) 483 ), 484 // https://www.w3.org/TR/mathml-core/#space-mspace 485 'mspace' => array_merge( 486 $math_global_attributes, 487 array( 488 'width' => true, 489 'height' => true, 490 'depth' => true, 491 ) 492 ), 493 // https://www.w3.org/TR/mathml-core/#string-literal-ms 494 'ms' => $math_global_attributes, 495 496 // https://www.w3.org/TR/mathml-core/#general-layout-schemata 497 // https://www.w3.org/TR/mathml-core/#horizontally-group-sub-expressions-mrow 498 'mrow' => $math_global_attributes, 499 // https://www.w3.org/TR/mathml-core/#fractions-mfrac 500 'mfrac' => array_merge( 501 $math_global_attributes, 502 array( 503 'linethickness' => true, 504 ) 505 ), 506 // https://www.w3.org/TR/mathml-core/#radicals-msqrt-mroot 507 'msqrt' => $math_global_attributes, 508 'mroot' => $math_global_attributes, 509 // https://www.w3.org/TR/mathml-core/#style-change-mstyle 510 'mstyle' => $math_global_attributes, 511 // https://www.w3.org/TR/mathml-core/#error-message-merror 512 'merror' => $math_global_attributes, 513 // https://www.w3.org/TR/mathml-core/#adjust-space-around-content-mpadded 514 'mpadded' => array_merge( 515 $math_global_attributes, 516 array( 517 'width' => true, 518 'height' => true, 519 'depth' => true, 520 'lspace' => true, 521 'voffset' => true, 522 ) 523 ), 524 // https://www.w3.org/TR/mathml-core/#making-sub-expressions-invisible-mphantom 525 'mphantom' => $math_global_attributes, 526 527 // https://www.w3.org/TR/mathml-core/#script-and-limit-schemata 528 // https://www.w3.org/TR/mathml-core/#subscripts-and-superscripts-msub-msup-msubsup 529 'msub' => $math_global_attributes, 530 'msup' => $math_global_attributes, 531 'msubsup' => $math_global_attributes, 532 // https://www.w3.org/TR/mathml-core/#underscripts-and-overscripts-munder-mover-munderover 533 'munder' => array_merge( $math_global_attributes, $math_overunder_attributes ), 534 'mover' => array_merge( $math_global_attributes, $math_overunder_attributes ), 535 'munderover' => array_merge( $math_global_attributes, $math_overunder_attributes ), 536 // https://www.w3.org/TR/mathml-core/#prescripts-and-tensor-indices-mmultiscripts 537 'mmultiscripts' => $math_global_attributes, 538 'mprescripts' => $math_global_attributes, 539 540 // https://www.w3.org/TR/mathml-core/#tabular-math 541 // https://www.w3.org/TR/mathml-core/#table-or-matrix-mtable 542 'mtable' => array_merge( 543 $math_global_attributes, 544 array( 545 // Non-standard, used by temml/katex. 546 // https://developer.mozilla.org/en-US/docs/Web/MathML/Reference/Element/mtable 547 'columnalign' => true, 548 'rowspacing' => true, 549 'columnspacing' => true, 550 'align' => true, 551 'rowalign' => true, 552 'columnlines' => true, 553 'rowlines' => true, 554 'frame' => true, 555 'framespacing' => true, 556 'width' => true, 557 ) 558 ), 559 // https://www.w3.org/TR/mathml-core/#row-in-table-or-matrix-mtr 560 'mtr' => array_merge( 561 $math_global_attributes, 562 array( 563 // Non-standard, used by temml/katex. 564 // https://developer.mozilla.org/en-US/docs/Web/MathML/Reference/Element/mtr 565 'columnalign' => true, 566 'rowalign' => true, 567 ) 568 ), 569 // https://www.w3.org/TR/mathml-core/#entry-in-table-or-matrix-mtd 570 'mtd' => array_merge( 571 $math_global_attributes, 572 array( 573 'columnspan' => true, 574 'rowspan' => true, 575 // Non-standard, used by temml/katex. 576 // https://developer.mozilla.org/en-US/docs/Web/MathML/Reference/Element/mtd 577 'columnalign' => true, 578 'rowalign' => true, 579 ) 580 ), 581 582 // https://www.w3.org/TR/mathml-core/#semantics-and-presentation 583 'semantics' => $math_global_attributes, 584 'annotation' => array_merge( 585 $math_global_attributes, 586 array( 587 'encoding' => true, 588 ) 589 ), 590 591 // Non-standard but widely supported, used by temml/katex. 592 'menclose' => array_merge( 593 $math_global_attributes, 594 array( 595 'notation' => true, 596 ) 597 ), 598 ) 599 ); 600 601 /** 602 * @var array[] $allowedtags Array of KSES allowed HTML elements. 603 * @since 1.0.0 604 */ 605 $allowedtags = array( 606 'a' => array( 607 'href' => true, 608 'title' => true, 609 ), 610 'abbr' => array( 611 'title' => true, 612 ), 613 'acronym' => array( 614 'title' => true, 615 ), 616 'b' => array(), 617 'blockquote' => array( 618 'cite' => true, 619 ), 620 'cite' => array(), 621 'code' => array(), 622 'del' => array( 623 'datetime' => true, 624 ), 625 'em' => array(), 626 'i' => array(), 627 'q' => array( 628 'cite' => true, 629 ), 630 's' => array(), 631 'strike' => array(), 632 'strong' => array(), 633 ); 634 635 /** 636 * @var string[] $allowedentitynames Array of KSES allowed HTML entity names. 637 * @since 1.0.0 638 */ 639 $allowedentitynames = array( 640 'nbsp', 641 'iexcl', 642 'cent', 643 'pound', 644 'curren', 645 'yen', 646 'brvbar', 647 'sect', 648 'uml', 649 'copy', 650 'ordf', 651 'laquo', 652 'not', 653 'shy', 654 'reg', 655 'macr', 656 'deg', 657 'plusmn', 658 'acute', 659 'micro', 660 'para', 661 'middot', 662 'cedil', 663 'ordm', 664 'raquo', 665 'iquest', 666 'Agrave', 667 'Aacute', 668 'Acirc', 669 'Atilde', 670 'Auml', 671 'Aring', 672 'AElig', 673 'Ccedil', 674 'Egrave', 675 'Eacute', 676 'Ecirc', 677 'Euml', 678 'Igrave', 679 'Iacute', 680 'Icirc', 681 'Iuml', 682 'ETH', 683 'Ntilde', 684 'Ograve', 685 'Oacute', 686 'Ocirc', 687 'Otilde', 688 'Ouml', 689 'times', 690 'Oslash', 691 'Ugrave', 692 'Uacute', 693 'Ucirc', 694 'Uuml', 695 'Yacute', 696 'THORN', 697 'szlig', 698 'agrave', 699 'aacute', 700 'acirc', 701 'atilde', 702 'auml', 703 'aring', 704 'aelig', 705 'ccedil', 706 'egrave', 707 'eacute', 708 'ecirc', 709 'euml', 710 'igrave', 711 'iacute', 712 'icirc', 713 'iuml', 714 'eth', 715 'ntilde', 716 'ograve', 717 'oacute', 718 'ocirc', 719 'otilde', 720 'ouml', 721 'divide', 722 'oslash', 723 'ugrave', 724 'uacute', 725 'ucirc', 726 'uuml', 727 'yacute', 728 'thorn', 729 'yuml', 730 'quot', 731 'amp', 732 'lt', 733 'gt', 734 'apos', 735 'OElig', 736 'oelig', 737 'Scaron', 738 'scaron', 739 'Yuml', 740 'circ', 741 'tilde', 742 'ensp', 743 'emsp', 744 'thinsp', 745 'zwnj', 746 'zwj', 747 'lrm', 748 'rlm', 749 'ndash', 750 'mdash', 751 'lsquo', 752 'rsquo', 753 'sbquo', 754 'ldquo', 755 'rdquo', 756 'bdquo', 757 'dagger', 758 'Dagger', 759 'permil', 760 'lsaquo', 761 'rsaquo', 762 'euro', 763 'fnof', 764 'Alpha', 765 'Beta', 766 'Gamma', 767 'Delta', 768 'Epsilon', 769 'Zeta', 770 'Eta', 771 'Theta', 772 'Iota', 773 'Kappa', 774 'Lambda', 775 'Mu', 776 'Nu', 777 'Xi', 778 'Omicron', 779 'Pi', 780 'Rho', 781 'Sigma', 782 'Tau', 783 'Upsilon', 784 'Phi', 785 'Chi', 786 'Psi', 787 'Omega', 788 'alpha', 789 'beta', 790 'gamma', 791 'delta', 792 'epsilon', 793 'zeta', 794 'eta', 795 'theta', 796 'iota', 797 'kappa', 798 'lambda', 799 'mu', 800 'nu', 801 'xi', 802 'omicron', 803 'pi', 804 'rho', 805 'sigmaf', 806 'sigma', 807 'tau', 808 'upsilon', 809 'phi', 810 'chi', 811 'psi', 812 'omega', 813 'thetasym', 814 'upsih', 815 'piv', 816 'bull', 817 'hellip', 818 'prime', 819 'Prime', 820 'oline', 821 'frasl', 822 'weierp', 823 'image', 824 'real', 825 'trade', 826 'alefsym', 827 'larr', 828 'uarr', 829 'rarr', 830 'darr', 831 'harr', 832 'crarr', 833 'lArr', 834 'uArr', 835 'rArr', 836 'dArr', 837 'hArr', 838 'forall', 839 'part', 840 'exist', 841 'empty', 842 'nabla', 843 'isin', 844 'notin', 845 'ni', 846 'prod', 847 'sum', 848 'minus', 849 'lowast', 850 'radic', 851 'prop', 852 'infin', 853 'ang', 854 'and', 855 'or', 856 'cap', 857 'cup', 858 'int', 859 'sim', 860 'cong', 861 'asymp', 862 'ne', 863 'equiv', 864 'le', 865 'ge', 866 'sub', 867 'sup', 868 'nsub', 869 'sube', 870 'supe', 871 'oplus', 872 'otimes', 873 'perp', 874 'sdot', 875 'lceil', 876 'rceil', 877 'lfloor', 878 'rfloor', 879 'lang', 880 'rang', 881 'loz', 882 'spades', 883 'clubs', 884 'hearts', 885 'diams', 886 'sup1', 887 'sup2', 888 'sup3', 889 'frac14', 890 'frac12', 891 'frac34', 892 'there4', 893 ); 894 895 /** 896 * @var string[] $allowedxmlentitynames Array of KSES allowed XML entity names. 897 * @since 5.5.0 898 */ 899 $allowedxmlentitynames = array( 900 'amp', 901 'lt', 902 'gt', 903 'apos', 904 'quot', 905 ); 906 907 $allowedposttags = array_map( '_wp_add_global_attributes', $allowedposttags ); 908 } else { 909 $required_kses_globals = array( 910 'allowedposttags', 911 'allowedtags', 912 'allowedentitynames', 913 'allowedxmlentitynames', 914 ); 915 $missing_kses_globals = array(); 916 917 foreach ( $required_kses_globals as $global_name ) { 918 if ( ! isset( $GLOBALS[ $global_name ] ) || ! is_array( $GLOBALS[ $global_name ] ) ) { 919 $missing_kses_globals[] = '<code>$' . $global_name . '</code>'; 920 } 921 } 922 923 if ( $missing_kses_globals ) { 924 _doing_it_wrong( 925 'wp_kses_allowed_html', 926 sprintf( 927 /* translators: 1: CUSTOM_TAGS, 2: Global variable names. */ 928 __( 'When using the %1$s constant, make sure to set these globals to an array: %2$s.' ), 929 '<code>CUSTOM_TAGS</code>', 930 implode( ', ', $missing_kses_globals ) 931 ), 932 '6.2.0' 933 ); 934 } 935 936 $allowedtags = wp_kses_array_lc( $allowedtags ); 937 $allowedposttags = wp_kses_array_lc( $allowedposttags ); 938 } 939 940 /** 941 * Filters text content and strips out disallowed HTML. 942 * 943 * This function makes sure that only the allowed HTML element names, attribute 944 * names, attribute values, and HTML entities will occur in the given text string. 945 * 946 * This function expects unslashed data. 947 * 948 * @see wp_kses_post() for specifically filtering post content and fields. 949 * @see wp_allowed_protocols() for the default allowed protocols in link URLs. 950 * 951 * @since 1.0.0 952 * 953 * @param string $content Text content to filter. 954 * @param array[]|string $allowed_html An array of allowed HTML elements and attributes, 955 * or a context name such as 'post'. See wp_kses_allowed_html() 956 * for the list of accepted context names. 957 * @param string[] $allowed_protocols Optional. Array of allowed URL protocols. 958 * Defaults to the result of wp_allowed_protocols(). 959 * @return string Filtered content containing only the allowed HTML. 960 */ 961 function wp_kses( $content, $allowed_html, $allowed_protocols = array() ) { 962 if ( empty( $allowed_protocols ) ) { 963 $allowed_protocols = wp_allowed_protocols(); 964 } 965 966 $content = wp_kses_no_null( $content, array( 'slash_zero' => 'keep' ) ); 967 $content = wp_kses_normalize_entities( $content ); 968 $content = wp_kses_hook( $content, $allowed_html, $allowed_protocols ); 969 970 return wp_kses_split( $content, $allowed_html, $allowed_protocols ); 971 } 972 973 /** 974 * Filters one HTML attribute and ensures its value is allowed. 975 * 976 * This function can escape data in some situations where `wp_kses()` must strip the whole attribute. 977 * 978 * @since 4.2.3 979 * 980 * @param string $attr The 'whole' attribute, including name and value. 981 * @param string $element The HTML element name to which the attribute belongs. 982 * @return string Filtered attribute. 983 */ 984 function wp_kses_one_attr( $attr, $element ) { 985 $uris = wp_kses_uri_attributes(); 986 $allowed_html = wp_kses_allowed_html( 'post' ); 987 $allowed_protocols = wp_allowed_protocols(); 988 $attr = wp_kses_no_null( $attr, array( 'slash_zero' => 'keep' ) ); 989 990 // Preserve leading and trailing whitespace. 991 $matches = array(); 992 preg_match( '/^\s*/', $attr, $matches ); 993 $lead = $matches[0]; 994 preg_match( '/\s*$/', $attr, $matches ); 995 $trail = $matches[0]; 996 if ( empty( $trail ) ) { 997 $attr = substr( $attr, strlen( $lead ) ); 998 } else { 999 $attr = substr( $attr, strlen( $lead ), -strlen( $trail ) ); 1000 } 1001 1002 // Parse attribute name and value from input. 1003 $split = preg_split( '/\s*=\s*/', $attr, 2 ); 1004 $name = $split[0]; 1005 if ( count( $split ) === 2 ) { 1006 $value = $split[1]; 1007 1008 /* 1009 * Remove quotes surrounding $value. 1010 * Also guarantee correct quoting in $attr for this one attribute. 1011 */ 1012 if ( '' === $value ) { 1013 $quote = ''; 1014 } else { 1015 $quote = $value[0]; 1016 } 1017 if ( '"' === $quote || "'" === $quote ) { 1018 if ( ! str_ends_with( $value, $quote ) ) { 1019 return ''; 1020 } 1021 $value = substr( $value, 1, -1 ); 1022 } else { 1023 $quote = '"'; 1024 } 1025 1026 // Sanitize quotes, angle braces, and entities. 1027 $value = esc_attr( $value ); 1028 1029 // Sanitize URI values. 1030 if ( in_array( strtolower( $name ), $uris, true ) ) { 1031 $value = wp_kses_bad_protocol( $value, $allowed_protocols ); 1032 } 1033 1034 $attr = "$name=$quote$value$quote"; 1035 $vless = 'n'; 1036 } else { 1037 $value = ''; 1038 $vless = 'y'; 1039 } 1040 1041 // Sanitize attribute by name. 1042 wp_kses_attr_check( $name, $value, $attr, $vless, $element, $allowed_html ); 1043 1044 // Restore whitespace. 1045 return $lead . $attr . $trail; 1046 } 1047 1048 /** 1049 * Returns an array of allowed HTML tags and attributes for a given context. 1050 * 1051 * @since 3.5.0 1052 * @since 5.0.1 `form` removed as allowable HTML tag. 1053 * 1054 * @global array $allowedposttags 1055 * @global array $allowedtags 1056 * @global array $allowedentitynames 1057 * 1058 * @param string|array $context The context for which to retrieve tags. Allowed values are 'post', 1059 * 'strip', 'data', 'entities', or the name of a field filter such as 1060 * 'pre_user_description', or an array of allowed HTML elements and attributes. 1061 * @return array Array of allowed HTML tags and their allowed attributes. 1062 */ 1063 function wp_kses_allowed_html( $context = '' ) { 1064 global $allowedposttags, $allowedtags, $allowedentitynames; 1065 1066 if ( is_array( $context ) ) { 1067 // When `$context` is an array it's actually an array of allowed HTML elements and attributes. 1068 $html = $context; 1069 $context = 'explicit'; 1070 1071 /** 1072 * Filters the HTML tags that are allowed for a given context. 1073 * 1074 * HTML tags and attribute names are case-insensitive in HTML but must be 1075 * added to the KSES allow list in lowercase. An item added to the allow list 1076 * in upper or mixed case will not recognized as permitted by KSES. 1077 * 1078 * @since 3.5.0 1079 * 1080 * @param array[] $html Allowed HTML tags. 1081 * @param string $context Context name. 1082 */ 1083 return apply_filters( 'wp_kses_allowed_html', $html, $context ); 1084 } 1085 1086 switch ( $context ) { 1087 case 'post': 1088 /** This filter is documented in wp-includes/kses.php */ 1089 $tags = apply_filters( 'wp_kses_allowed_html', $allowedposttags, $context ); 1090 1091 // 5.0.1 removed the `<form>` tag, allow it if a filter is allowing it's sub-elements `<input>` or `<select>`. 1092 if ( ! CUSTOM_TAGS && ! isset( $tags['form'] ) && ( isset( $tags['input'] ) || isset( $tags['select'] ) ) ) { 1093 $tags = $allowedposttags; 1094 1095 $tags['form'] = array( 1096 'action' => true, 1097 'accept' => true, 1098 'accept-charset' => true, 1099 'enctype' => true, 1100 'method' => true, 1101 'name' => true, 1102 'target' => true, 1103 ); 1104 1105 /** This filter is documented in wp-includes/kses.php */ 1106 $tags = apply_filters( 'wp_kses_allowed_html', $tags, $context ); 1107 } 1108 1109 return $tags; 1110 1111 case 'user_description': 1112 case 'pre_term_description': 1113 case 'pre_user_description': 1114 $tags = $allowedtags; 1115 $tags['a']['rel'] = true; 1116 $tags['a']['target'] = true; 1117 /** This filter is documented in wp-includes/kses.php */ 1118 return apply_filters( 'wp_kses_allowed_html', $tags, $context ); 1119 1120 case 'strip': 1121 /** This filter is documented in wp-includes/kses.php */ 1122 return apply_filters( 'wp_kses_allowed_html', array(), $context ); 1123 1124 case 'entities': 1125 /** This filter is documented in wp-includes/kses.php */ 1126 return apply_filters( 'wp_kses_allowed_html', $allowedentitynames, $context ); 1127 1128 case 'data': 1129 default: 1130 /** This filter is documented in wp-includes/kses.php */ 1131 return apply_filters( 'wp_kses_allowed_html', $allowedtags, $context ); 1132 } 1133 } 1134 1135 /** 1136 * Allows the note mention chip markup in comment content. 1137 * 1138 * The notes `@` mention completer stores a mention as a chip carrying the 1139 * mentioned user's ID in a class token: 1140 * `<span class="wp-note-mention user-N">@Name</span>`. The default comment 1141 * allowlist does not allow `span` at all, so for users without 1142 * `unfiltered_html` the mention would be stripped on save. 1143 * 1144 * The allowance is deliberately narrow and always on: `span` is a 1145 * semantics-free element and _wp_kses_sanitize_note_mention_classes() 1146 * reduces its `class` to the two mention tokens right after kses runs, so 1147 * regular (including anonymous) commenters gain nothing beyond the inert 1148 * mention markup itself. 1149 * 1150 * @since 7.1.0 1151 * @access private 1152 * 1153 * @param array<string, array<string, bool>> $allowed The allowed tags structure for the context. 1154 * @param string $context The kses context. 1155 * @return array<string, array<string, bool>> Modified allowed tags structure. 1156 */ 1157 function _wp_kses_allow_note_mention_span( $allowed, $context ): array { 1158 if ( ! is_array( $allowed ) ) { 1159 $allowed = array(); 1160 } 1161 if ( 'pre_comment_content' !== $context ) { 1162 return $allowed; 1163 } 1164 1165 if ( ! isset( $allowed['span'] ) || ! is_array( $allowed['span'] ) ) { 1166 $allowed['span'] = array(); 1167 } 1168 1169 $allowed['span']['class'] = true; 1170 1171 return $allowed; 1172 } 1173 1174 /** 1175 * Reduces `span` classes in comment content to the note mention tokens. 1176 * 1177 * _wp_kses_allow_note_mention_span() lets `class` through kses on `span` so 1178 * the mention chip survives, but `class` is an open-ended styling and 1179 * scripting hook, so this companion pass - running right after 1180 * `wp_filter_kses` at priority 10 - strips every class token except the two 1181 * the mention markup uses: `wp-note-mention` and `user-N`. `span` is the only 1182 * comment tag allowed to carry `class` at all, so walking `span` tags covers 1183 * the entire allowance. 1184 * 1185 * The pass only applies while the restrictive comment allowlist is active: 1186 * users with `unfiltered_html` are filtered through `wp_filter_post_kses` 1187 * (or not at all), where arbitrary classes are already permitted, and 1188 * narrowing their markup here would restrict what core allows them to post. 1189 * 1190 * @since 7.1.0 1191 * @access private 1192 * 1193 * @param string $content Slashed comment content, already filtered by kses. 1194 * @return string Slashed comment content with span classes reduced. 1195 */ 1196 function _wp_kses_sanitize_note_mention_classes( $content ): string { 1197 if ( ! is_string( $content ) ) { 1198 $content = ''; 1199 } 1200 if ( false === has_filter( 'pre_comment_content', 'wp_filter_kses' ) ) { 1201 return $content; 1202 } 1203 1204 $processor = new WP_HTML_Tag_Processor( wp_unslash( $content ) ); 1205 1206 while ( $processor->next_tag( 'SPAN' ) ) { 1207 foreach ( $processor->class_list() as $token ) { 1208 if ( 'wp-note-mention' !== $token && ! preg_match( '/^user-[1-9][0-9]*$/', $token ) ) { 1209 // Removing the last class also removes the attribute itself. 1210 $processor->remove_class( $token ); 1211 } 1212 } 1213 } 1214 1215 return wp_slash( $processor->get_updated_html() ); 1216 } 1217 1218 /** 1219 * You add any KSES hooks here. 1220 * 1221 * There is currently only one KSES WordPress hook, {@see 'pre_kses'}, and it is called here. 1222 * All parameters are passed to the hooks and expected to receive a string. 1223 * 1224 * @since 1.0.0 1225 * 1226 * @param string $content Content to filter through KSES. 1227 * @param array[]|string $allowed_html An array of allowed HTML elements and attributes, 1228 * or a context name such as 'post'. See wp_kses_allowed_html() 1229 * for the list of accepted context names. 1230 * @param string[] $allowed_protocols Array of allowed URL protocols. 1231 * @return string Filtered content through {@see 'pre_kses'} hook. 1232 */ 1233 function wp_kses_hook( $content, $allowed_html, $allowed_protocols ) { 1234 /** 1235 * Filters content to be run through KSES. 1236 * 1237 * @since 2.3.0 1238 * 1239 * @param string $content Content to filter through KSES. 1240 * @param array[]|string $allowed_html An array of allowed HTML elements and attributes, 1241 * or a context name such as 'post'. See wp_kses_allowed_html() 1242 * for the list of accepted context names. 1243 * @param string[] $allowed_protocols Array of allowed URL protocols. 1244 */ 1245 return apply_filters( 'pre_kses', $content, $allowed_html, $allowed_protocols ); 1246 } 1247 1248 /** 1249 * Returns the version number of KSES. 1250 * 1251 * @since 1.0.0 1252 * 1253 * @return string KSES version number. 1254 */ 1255 function wp_kses_version() { 1256 return '0.2.2'; 1257 } 1258 1259 /** 1260 * Searches for HTML tags, no matter how malformed. 1261 * 1262 * It also matches stray `>` characters. 1263 * 1264 * @since 1.0.0 1265 * @since 6.6.0 Recognize additional forms of invalid HTML which convert into comments. 1266 * 1267 * @global array[]|string $pass_allowed_html An array of allowed HTML elements and attributes, 1268 * or a context name such as 'post'. 1269 * @global string[] $pass_allowed_protocols Array of allowed URL protocols. 1270 * 1271 * @param string $content Content to filter. 1272 * @param array[]|string $allowed_html An array of allowed HTML elements and attributes, 1273 * or a context name such as 'post'. See wp_kses_allowed_html() 1274 * for the list of accepted context names. 1275 * @param string[] $allowed_protocols Array of allowed URL protocols. 1276 * @return string Content with fixed HTML tags 1277 */ 1278 function wp_kses_split( $content, $allowed_html, $allowed_protocols ) { 1279 global $pass_allowed_html, $pass_allowed_protocols; 1280 1281 $pass_allowed_html = $allowed_html; 1282 $pass_allowed_protocols = $allowed_protocols; 1283 1284 $token_pattern = <<<REGEX 1285 ~ 1286 ( # Detect comments of various flavors before attempting to find tags. 1287 (<!--.*?(-->|$)) # - Normative HTML comments. 1288 | 1289 </[^a-zA-Z][^>]*> # - Closing tags with invalid tag names. 1290 | 1291 <![^>]*> # - Invalid markup declaration nodes. Not all invalid nodes 1292 # are matched so as to avoid breaking legacy behaviors. 1293 ) 1294 | 1295 (<[^>]*(>|$)|>) # Tag-like spans of text. 1296 ~x 1297 REGEX; 1298 return preg_replace_callback( $token_pattern, '_wp_kses_split_callback', $content ); 1299 } 1300 1301 /** 1302 * Returns an array of HTML attribute names whose value contains a URL. 1303 * 1304 * This function returns a list of all HTML attributes that must contain 1305 * a URL according to the HTML specification. 1306 * 1307 * This list includes URI attributes both allowed and disallowed by KSES. 1308 * 1309 * @link https://developer.mozilla.org/en-US/docs/Web/HTML/Attributes 1310 * 1311 * @since 5.0.1 1312 * 1313 * @return string[] HTML attribute names whose value contains a URL. 1314 */ 1315 function wp_kses_uri_attributes() { 1316 $uri_attributes = array( 1317 'action', 1318 'archive', 1319 'background', 1320 'cite', 1321 'classid', 1322 'codebase', 1323 'data', 1324 'formaction', 1325 'href', 1326 'icon', 1327 'longdesc', 1328 'manifest', 1329 'poster', 1330 'profile', 1331 'src', 1332 'usemap', 1333 'xmlns', 1334 ); 1335 1336 /** 1337 * Filters the list of attributes that are required to contain a URL. 1338 * 1339 * Use this filter to add any `data-` attributes that are required to be 1340 * validated as a URL. 1341 * 1342 * @since 5.0.1 1343 * 1344 * @param string[] $uri_attributes HTML attribute names whose value contains a URL. 1345 */ 1346 $uri_attributes = apply_filters( 'wp_kses_uri_attributes', $uri_attributes ); 1347 1348 return $uri_attributes; 1349 } 1350 1351 /** 1352 * Callback for `wp_kses_split()`. 1353 * 1354 * @since 3.1.0 1355 * @access private 1356 * @ignore 1357 * 1358 * @global array[]|string $pass_allowed_html An array of allowed HTML elements and attributes, 1359 * or a context name such as 'post'. 1360 * @global string[] $pass_allowed_protocols Array of allowed URL protocols. 1361 * 1362 * @param array $matches preg_replace regexp matches 1363 * @return string 1364 */ 1365 function _wp_kses_split_callback( $matches ) { 1366 global $pass_allowed_html, $pass_allowed_protocols; 1367 1368 return wp_kses_split2( $matches[0], $pass_allowed_html, $pass_allowed_protocols ); 1369 } 1370 1371 /** 1372 * Callback for `wp_kses_split()` for fixing malformed HTML tags. 1373 * 1374 * This function does a lot of work. It rejects some very malformed things like 1375 * `<:::>`. It returns an empty string, if the element isn't allowed (look ma, no 1376 * `strip_tags()`!). Otherwise it splits the tag into an element and an attribute 1377 * list. 1378 * 1379 * After the tag is split into an element and an attribute list, it is run 1380 * through another filter which will remove illegal attributes and once that is 1381 * completed, will be returned. 1382 * 1383 * @access private 1384 * @ignore 1385 * @since 1.0.0 1386 * @since 6.6.0 Recognize additional forms of invalid HTML which convert into comments. 1387 * 1388 * @param string $content Content to filter. 1389 * @param array[]|string $allowed_html An array of allowed HTML elements and attributes, 1390 * or a context name such as 'post'. See wp_kses_allowed_html() 1391 * for the list of accepted context names. 1392 * @param string[] $allowed_protocols Array of allowed URL protocols. 1393 * 1394 * @return string Fixed HTML element 1395 */ 1396 function wp_kses_split2( $content, $allowed_html, $allowed_protocols ) { 1397 $content = wp_kses_stripslashes( $content ); 1398 1399 /* 1400 * The regex pattern used to split HTML into chunks attempts 1401 * to split on HTML token boundaries. This function should 1402 * thus receive chunks that _either_ start with meaningful 1403 * syntax tokens, like a tag `<div>` or a comment `<!-- ... -->`. 1404 * 1405 * If the first character of the `$content` chunk _isn't_ one 1406 * of these syntax elements, which always starts with `<`, then 1407 * the match had to be for the final alternation of `>`. In such 1408 * case, it's probably standing on its own and could be encoded 1409 * with a character reference to remove ambiguity. 1410 * 1411 * In other words, if this chunk isn't from a match of a syntax 1412 * token, it's just a plaintext greater-than (`>`) sign. 1413 */ 1414 if ( ! str_starts_with( $content, '<' ) ) { 1415 return '>'; 1416 } 1417 1418 /* 1419 * When certain invalid syntax constructs appear, the HTML parser 1420 * shifts into what's called the "bogus comment state." This is a 1421 * plaintext state that consumes everything until the nearest `>` 1422 * and then transforms the entire span into an HTML comment. 1423 * 1424 * Preserve these comments and do not treat them like tags. 1425 * 1426 * @see https://html.spec.whatwg.org/#bogus-comment-state 1427 */ 1428 if ( 1 === preg_match( '~^(?:</[^a-zA-Z][^>]*>|<![a-z][^>]*>)$~', $content ) ) { 1429 /** 1430 * Since the pattern matches `</…>` and also `<!…>`, this will 1431 * preserve the type of the cleaned-up token in the output. 1432 */ 1433 $opener = $content[1]; 1434 $content = substr( $content, 2, -1 ); 1435 1436 do { 1437 $prev = $content; 1438 $content = wp_kses( $content, $allowed_html, $allowed_protocols ); 1439 } while ( $prev !== $content ); 1440 1441 // Recombine the modified inner content with the original token structure. 1442 return "<{$opener}{$content}>"; 1443 } 1444 1445 /* 1446 * Normative HTML comments should be handled separately as their 1447 * parsing rules differ from those for tags and text nodes. 1448 */ 1449 if ( str_starts_with( $content, '<!--' ) ) { 1450 $content = str_replace( array( '<!--', '-->' ), '', $content ); 1451 1452 while ( ( $newstring = wp_kses( $content, $allowed_html, $allowed_protocols ) ) !== $content ) { 1453 $content = $newstring; 1454 } 1455 1456 if ( '' === $content ) { 1457 return ''; 1458 } 1459 1460 // Prevent multiple dashes in comments. 1461 $content = preg_replace( '/--+/', '-', $content ); 1462 // Prevent three dashes closing a comment. 1463 $content = preg_replace( '/-$/', '', $content ); 1464 1465 return "<!--{$content}-->"; 1466 } 1467 1468 // It's seriously malformed. 1469 if ( ! preg_match( '%^<\s*(/\s*)?([a-zA-Z0-9-]+)([^>]*)>?$%', $content, $matches ) ) { 1470 return ''; 1471 } 1472 1473 $slash = trim( $matches[1] ); 1474 $elem = $matches[2]; 1475 $attrlist = $matches[3]; 1476 1477 if ( ! is_array( $allowed_html ) ) { 1478 $allowed_html = wp_kses_allowed_html( $allowed_html ); 1479 } 1480 1481 // They are using a not allowed HTML element. 1482 if ( ! isset( $allowed_html[ strtolower( $elem ) ] ) ) { 1483 return ''; 1484 } 1485 1486 // No attributes are allowed for closing elements. 1487 if ( '' !== $slash ) { 1488 return "</$elem>"; 1489 } 1490 1491 return wp_kses_attr( $elem, $attrlist, $allowed_html, $allowed_protocols ); 1492 } 1493 1494 /** 1495 * Removes all attributes, if none are allowed for this element. 1496 * 1497 * If some are allowed it calls `wp_kses_hair()` to split them further, and then 1498 * it builds up new HTML code from the data that `wp_kses_hair()` returns. It also 1499 * removes `<` and `>` characters, if there are any left. One more thing it does 1500 * is to check if the tag has a closing XHTML slash, and if it does, it puts one 1501 * in the returned code as well. 1502 * 1503 * An array of allowed values can be defined for attributes. If the attribute value 1504 * doesn't fall into the list, the attribute will be removed from the tag. 1505 * 1506 * Attributes can be marked as required. If a required attribute is not present, 1507 * KSES will remove all attributes from the tag. As KSES doesn't match opening and 1508 * closing tags, it's not possible to safely remove the tag itself, the safest 1509 * fallback is to strip all attributes from the tag, instead. 1510 * 1511 * @since 1.0.0 1512 * @since 5.9.0 Added support for an array of allowed values for attributes. 1513 * Added support for required attributes. 1514 * 1515 * @param string $element HTML element/tag. 1516 * @param string $attr HTML attributes from HTML element to closing HTML element tag. 1517 * @param array[]|string $allowed_html An array of allowed HTML elements and attributes, 1518 * or a context name such as 'post'. See wp_kses_allowed_html() 1519 * for the list of accepted context names. 1520 * @param string[] $allowed_protocols Array of allowed URL protocols. 1521 * @return string Sanitized HTML element. 1522 */ 1523 function wp_kses_attr( $element, $attr, $allowed_html, $allowed_protocols ) { 1524 if ( ! is_array( $allowed_html ) ) { 1525 $allowed_html = wp_kses_allowed_html( $allowed_html ); 1526 } 1527 1528 // Is there a closing XHTML slash at the end of the attributes? 1529 $xhtml_slash = ''; 1530 if ( preg_match( '%\s*/\s*$%', $attr ) ) { 1531 $xhtml_slash = ' /'; 1532 } 1533 1534 // Are any attributes allowed at all for this element? 1535 $element_low = strtolower( $element ); 1536 if ( empty( $allowed_html[ $element_low ] ) || true === $allowed_html[ $element_low ] ) { 1537 return "<$element$xhtml_slash>"; 1538 } 1539 1540 // Split it. 1541 $attrarr = wp_kses_hair( $attr, $allowed_protocols ); 1542 1543 // Check if there are attributes that are required. 1544 $required_attrs = array_filter( 1545 $allowed_html[ $element_low ], 1546 static function ( $required_attr_limits ) { 1547 return isset( $required_attr_limits['required'] ) && true === $required_attr_limits['required']; 1548 } 1549 ); 1550 1551 /* 1552 * If a required attribute check fails, we can return nothing for a self-closing tag, 1553 * but for a non-self-closing tag the best option is to return the element with attributes, 1554 * as KSES doesn't handle matching the relevant closing tag. 1555 */ 1556 $stripped_tag = ''; 1557 if ( empty( $xhtml_slash ) ) { 1558 $stripped_tag = "<$element>"; 1559 } 1560 1561 // Go through $attrarr, and save the allowed attributes for this element in $attr2. 1562 $attr2 = ''; 1563 foreach ( $attrarr as $arreach ) { 1564 // Check if this attribute is required. 1565 $required = isset( $required_attrs[ strtolower( $arreach['name'] ) ] ); 1566 1567 if ( wp_kses_attr_check( $arreach['name'], $arreach['value'], $arreach['whole'], $arreach['vless'], $element, $allowed_html ) ) { 1568 $attr2 .= ' ' . $arreach['whole']; 1569 1570 // If this was a required attribute, we can mark it as found. 1571 if ( $required ) { 1572 unset( $required_attrs[ strtolower( $arreach['name'] ) ] ); 1573 } 1574 } elseif ( $required ) { 1575 // This attribute was required, but didn't pass the check. The entire tag is not allowed. 1576 return $stripped_tag; 1577 } 1578 } 1579 1580 // If some required attributes weren't set, the entire tag is not allowed. 1581 if ( ! empty( $required_attrs ) ) { 1582 return $stripped_tag; 1583 } 1584 1585 // Remove any "<" or ">" characters. 1586 $attr2 = preg_replace( '/[<>]/', '', $attr2 ); 1587 1588 return "<$element$attr2$xhtml_slash>"; 1589 } 1590 1591 /** 1592 * Determines whether an attribute is allowed. 1593 * 1594 * @since 4.2.3 1595 * @since 5.0.0 Added support for `data-*` wildcard attributes. 1596 * 1597 * @param string $name The attribute name. Passed by reference. Returns empty string when not allowed. 1598 * @param string $value The attribute value. Passed by reference. Returns a filtered value. 1599 * @param string $whole The `name=value` input. Passed by reference. Returns filtered input. 1600 * @param string $vless Whether the attribute is valueless. Use 'y' or 'n'. 1601 * @param string $element The name of the element to which this attribute belongs. 1602 * @param array $allowed_html The full list of allowed elements and attributes. 1603 * @return bool Whether or not the attribute is allowed. 1604 */ 1605 function wp_kses_attr_check( &$name, &$value, &$whole, $vless, $element, $allowed_html ) { 1606 $name_low = strtolower( $name ); 1607 $element_low = strtolower( $element ); 1608 1609 if ( ! isset( $allowed_html[ $element_low ] ) ) { 1610 $name = ''; 1611 $value = ''; 1612 $whole = ''; 1613 return false; 1614 } 1615 1616 $allowed_attr = $allowed_html[ $element_low ]; 1617 1618 if ( ! isset( $allowed_attr[ $name_low ] ) || '' === $allowed_attr[ $name_low ] ) { 1619 /* 1620 * Allow `data-*` attributes. 1621 * 1622 * When specifying `$allowed_html`, the attribute name should be set as 1623 * `data-*` (not to be mixed with the HTML 4.0 `data` attribute, see 1624 * https://www.w3.org/TR/html40/struct/objects.html#adef-data). 1625 * 1626 * Note: the attribute name should only contain `A-Za-z0-9_-` chars. 1627 */ 1628 if ( str_starts_with( $name_low, 'data-' ) && ! empty( $allowed_attr['data-*'] ) 1629 && preg_match( '/^data-[a-z0-9_-]+$/', $name_low, $match ) 1630 ) { 1631 /* 1632 * Add the whole attribute name to the allowed attributes and set any restrictions 1633 * for the `data-*` attribute values for the current element. 1634 */ 1635 $allowed_attr[ $match[0] ] = $allowed_attr['data-*']; 1636 } else { 1637 $name = ''; 1638 $value = ''; 1639 $whole = ''; 1640 return false; 1641 } 1642 } 1643 1644 if ( 'style' === $name_low ) { 1645 $decoded_value = WP_HTML_Decoder::decode_attribute( $value ); 1646 $new_value = safecss_filter_attr( $decoded_value ); 1647 1648 if ( empty( $new_value ) ) { 1649 $name = ''; 1650 $value = ''; 1651 $whole = ''; 1652 return false; 1653 } 1654 1655 if ( $new_value !== $decoded_value ) { 1656 $encoded_value = esc_attr( $new_value ); 1657 $whole = str_replace( $value, $encoded_value, $whole ); 1658 $value = $encoded_value; 1659 } 1660 } 1661 1662 if ( is_array( $allowed_attr[ $name_low ] ) ) { 1663 // There are some checks. 1664 foreach ( $allowed_attr[ $name_low ] as $currkey => $currval ) { 1665 if ( ! wp_kses_check_attr_val( $value, $vless, $currkey, $currval ) ) { 1666 $name = ''; 1667 $value = ''; 1668 $whole = ''; 1669 return false; 1670 } 1671 } 1672 } 1673 1674 return true; 1675 } 1676 1677 /** 1678 * Given a string of HTML attributes and values, parse into a structured attribute list. 1679 * 1680 * This function performs a number of transformations while parsing attribute strings: 1681 * - It normalizes attribute values and surrounds them with double quotes. 1682 * - It normalizes HTML character references inside attribute values. 1683 * - It removes “bad” URL protocols from attribute values. 1684 * 1685 * Otherwise this reads the attributes as if they were part of an HTML tag. It performs 1686 * these transformations to lower the risk of mis-parsing down the line and to perform 1687 * URL sanitization in line with the rest of the `kses` subsystem. Importantly, it does 1688 * not decode the attribute values, meaning that special HTML syntax characters will 1689 * be left with character references in the `value` property. 1690 * 1691 * Example: 1692 * 1693 * $attrs = wp_kses_hair( 'class="is-wide" inert data-lazy=\'<img>\' =/🐮=/' ); 1694 * $attrs === array( 1695 * 'class' => array( 'name' => 'class', 'value' => 'is-wide', 'whole' => 'class="is-wide"', 'vless' => 'n' ), 1696 * 'inert' => array( 'name' => 'inert', 'value' => '', 'whole' => 'inert', 'vless' => 'y' ), 1697 * 'data-lazy' => array( 'name' => 'data-lazy', 'value' => '<img>', 'whole' => 'data-lazy="<img>"', 'vless' => 'n' ), 1698 * '=' => array( 'name' => '=', 'value' => '', 'whole' => '=', 'vless' => 'y' ), 1699 * '🐮' => array( 'name' => '🐮', 'value' => '/', 'whole' => '🐮="/"', 'vless' => 'n' ), 1700 * ); 1701 * 1702 * @since 1.0.0 1703 * @since 7.0.0 Reliably parses HTML via the HTML API. 1704 * 1705 * @param string $attr Attribute list from HTML element to closing HTML element tag. 1706 * @param string[] $allowed_protocols Array of allowed URL protocols. 1707 * @return array<string, array{name: string, value: string, whole: string, vless: 'y'|'n'}> Array of attribute information after parsing. 1708 */ 1709 function wp_kses_hair( $attr, $allowed_protocols ) { 1710 $attributes = array(); 1711 $uris = wp_kses_uri_attributes(); 1712 1713 $processor = new WP_HTML_Tag_Processor( "<wp {$attr}>" ); 1714 $processor->next_token(); 1715 1716 $attribute_names = $processor->get_attribute_names_with_prefix( '' ); 1717 if ( null === $attribute_names || 0 === count( $attribute_names ) ) { 1718 return $attributes; 1719 } 1720 1721 $syntax_characters = array( 1722 '&' => '&', 1723 '<' => '<', 1724 '>' => '>', 1725 "'" => ''', 1726 '"' => '"', 1727 ); 1728 1729 foreach ( $attribute_names as $name ) { 1730 $value = $processor->get_attribute( $name ); 1731 $is_bool = true === $value; 1732 if ( is_string( $value ) && in_array( $name, $uris, true ) ) { 1733 $value = wp_kses_bad_protocol( $value, $allowed_protocols ); 1734 } 1735 1736 // Reconstruct and normalize the attribute value. 1737 $recoded = $is_bool ? '' : strtr( $value, $syntax_characters ); 1738 $whole = $is_bool ? $name : "{$name}=\"{$recoded}\""; 1739 1740 $attributes[ $name ] = array( 1741 'name' => $name, 1742 'value' => $recoded, 1743 'whole' => $whole, 1744 'vless' => $is_bool ? 'y' : 'n', 1745 ); 1746 } 1747 1748 return $attributes; 1749 } 1750 1751 /** 1752 * Finds all attributes of an HTML element. 1753 * 1754 * Does not modify input. May return "evil" output. 1755 * 1756 * Based on `wp_kses_split2()` and `wp_kses_attr()`. 1757 * 1758 * @since 4.2.3 1759 * 1760 * @param string $element HTML element. 1761 * @return array|false List of attributes found in the element. Returns false on failure. 1762 */ 1763 function wp_kses_attr_parse( $element ) { 1764 $valid = preg_match( '%^(<\s*)(/\s*)?([a-zA-Z0-9]+\s*)([^>]*)(>?)$%', $element, $matches ); 1765 if ( 1 !== $valid ) { 1766 return false; 1767 } 1768 1769 $begin = $matches[1]; 1770 $slash = $matches[2]; 1771 $elname = $matches[3]; 1772 $attr = $matches[4]; 1773 $end = $matches[5]; 1774 1775 if ( '' !== $slash ) { 1776 // Closing elements do not get parsed. 1777 return false; 1778 } 1779 1780 // Is there a closing XHTML slash at the end of the attributes? 1781 if ( 1 === preg_match( '%\s*/\s*$%', $attr, $matches ) ) { 1782 $xhtml_slash = $matches[0]; 1783 $attr = substr( $attr, 0, -strlen( $xhtml_slash ) ); 1784 } else { 1785 $xhtml_slash = ''; 1786 } 1787 1788 // Split it. 1789 $attrarr = wp_kses_hair_parse( $attr ); 1790 if ( false === $attrarr ) { 1791 return false; 1792 } 1793 1794 // Make sure all input is returned by adding front and back matter. 1795 array_unshift( $attrarr, $begin . $slash . $elname ); 1796 array_push( $attrarr, $xhtml_slash . $end ); 1797 1798 return $attrarr; 1799 } 1800 1801 /** 1802 * Builds an attribute list from string containing attributes. 1803 * 1804 * Does not modify input. May return "evil" output. 1805 * In case of unexpected input, returns false instead of stripping things. 1806 * 1807 * Based on `wp_kses_hair()` but does not return a multi-dimensional array. 1808 * 1809 * @since 4.2.3 1810 * 1811 * @param string $attr Attribute list from HTML element to closing HTML element tag. 1812 * @return array|false List of attributes found in $attr. Returns false on failure. 1813 */ 1814 function wp_kses_hair_parse( $attr ) { 1815 if ( '' === $attr ) { 1816 return array(); 1817 } 1818 1819 $regex = 1820 '(?: 1821 [_a-zA-Z][-_a-zA-Z0-9:.]* # Attribute name. 1822 | 1823 \[\[?[^\[\]]+\]\]? # Shortcode in the name position implies unfiltered_html. 1824 ) 1825 (?: # Attribute value. 1826 \s*=\s* # All values begin with "=". 1827 (?: 1828 "[^"]*" # Double-quoted. 1829 | 1830 \'[^\']*\' # Single-quoted. 1831 | 1832 [^\s"\']+ # Non-quoted. 1833 (?:\s|$) # Must have a space. 1834 ) 1835 | 1836 (?:\s|$) # If attribute has no value, space is required. 1837 ) 1838 \s* # Trailing space is optional except as mentioned above. 1839 '; 1840 1841 /* 1842 * Although it is possible to reduce this procedure to a single regexp, 1843 * we must run that regexp twice to get exactly the expected result. 1844 * 1845 * Note: do NOT remove the `x` modifiers as they are essential for the above regex! 1846 */ 1847 1848 $validation = "/^($regex)+$/x"; 1849 $extraction = "/$regex/x"; 1850 1851 if ( 1 === preg_match( $validation, $attr ) ) { 1852 preg_match_all( $extraction, $attr, $attrarr ); 1853 return $attrarr[0]; 1854 } else { 1855 return false; 1856 } 1857 } 1858 1859 /** 1860 * Performs different checks for attribute values. 1861 * 1862 * The currently implemented checks are "maxlen", "minlen", "maxval", "minval", 1863 * and "valueless". 1864 * 1865 * @since 1.0.0 1866 * 1867 * @param string $value Attribute value. 1868 * @param string $vless Whether the attribute is valueless. Use 'y' or 'n'. 1869 * @param string $checkname What $checkvalue is checking for. 1870 * @param mixed $checkvalue What constraint the value should pass. 1871 * @return bool Whether check passes. 1872 */ 1873 function wp_kses_check_attr_val( $value, $vless, $checkname, $checkvalue ) { 1874 $ok = true; 1875 1876 switch ( strtolower( $checkname ) ) { 1877 case 'maxlen': 1878 /* 1879 * The maxlen check makes sure that the attribute value has a length not 1880 * greater than the given value. This can be used to avoid Buffer Overflows 1881 * in WWW clients and various Internet servers. 1882 */ 1883 1884 if ( strlen( $value ) > $checkvalue ) { 1885 $ok = false; 1886 } 1887 break; 1888 1889 case 'minlen': 1890 /* 1891 * The minlen check makes sure that the attribute value has a length not 1892 * smaller than the given value. 1893 */ 1894 1895 if ( strlen( $value ) < $checkvalue ) { 1896 $ok = false; 1897 } 1898 break; 1899 1900 case 'maxval': 1901 /* 1902 * The maxval check does two things: it checks that the attribute value is 1903 * an integer from 0 and up, without an excessive amount of zeroes or 1904 * whitespace (to avoid Buffer Overflows). It also checks that the attribute 1905 * value is not greater than the given value. 1906 * This check can be used to avoid Denial of Service attacks. 1907 */ 1908 1909 if ( ! preg_match( '/^\s{0,6}[0-9]{1,6}\s{0,6}$/', $value ) ) { 1910 $ok = false; 1911 } 1912 if ( $value > $checkvalue ) { 1913 $ok = false; 1914 } 1915 break; 1916 1917 case 'minval': 1918 /* 1919 * The minval check makes sure that the attribute value is a positive integer, 1920 * and that it is not smaller than the given value. 1921 */ 1922 1923 if ( ! preg_match( '/^\s{0,6}[0-9]{1,6}\s{0,6}$/', $value ) ) { 1924 $ok = false; 1925 } 1926 if ( $value < $checkvalue ) { 1927 $ok = false; 1928 } 1929 break; 1930 1931 case 'valueless': 1932 /* 1933 * The valueless check makes sure if the attribute has a value 1934 * (like `<a href="blah">`) or not (`<option selected>`). If the given value 1935 * is a "y" or a "Y", the attribute must not have a value. 1936 * If the given value is an "n" or an "N", the attribute must have a value. 1937 */ 1938 1939 if ( strtolower( $checkvalue ) !== $vless ) { 1940 $ok = false; 1941 } 1942 break; 1943 1944 case 'values': 1945 /* 1946 * The values check is used when you want to make sure that the attribute 1947 * has one of the given values. 1948 */ 1949 1950 if ( ! in_array( strtolower( $value ), $checkvalue, true ) ) { 1951 $ok = false; 1952 } 1953 break; 1954 1955 case 'value_callback': 1956 /* 1957 * The value_callback check is used when you want to make sure that the attribute 1958 * value is accepted by the callback function. 1959 */ 1960 1961 if ( ! call_user_func( $checkvalue, $value ) ) { 1962 $ok = false; 1963 } 1964 break; 1965 } // End switch. 1966 1967 return $ok; 1968 } 1969 1970 /** 1971 * Sanitizes a string and removed disallowed URL protocols. 1972 * 1973 * This function removes all non-allowed protocols from the beginning of the 1974 * string. It ignores whitespace and the case of the letters, and it does 1975 * understand HTML entities. It does its work recursively, so it won't be 1976 * fooled by a string like `javascript:javascript:alert(57)`. 1977 * 1978 * @since 1.0.0 1979 * 1980 * @param string $content Content to filter bad protocols from. 1981 * @param string[] $allowed_protocols Array of allowed URL protocols. 1982 * @return string Filtered content. 1983 */ 1984 function wp_kses_bad_protocol( $content, $allowed_protocols ) { 1985 $content = wp_kses_no_null( $content ); 1986 1987 // Short-circuit if the string starts with `https://` or `http://`. Most common cases. 1988 if ( 1989 ( str_starts_with( $content, 'https://' ) && in_array( 'https', $allowed_protocols, true ) ) || 1990 ( str_starts_with( $content, 'http://' ) && in_array( 'http', $allowed_protocols, true ) ) 1991 ) { 1992 return $content; 1993 } 1994 1995 $iterations = 0; 1996 1997 do { 1998 $original_content = $content; 1999 $content = wp_kses_bad_protocol_once( $content, $allowed_protocols ); 2000 } while ( $original_content !== $content && ++$iterations < 6 ); 2001 2002 if ( $original_content !== $content ) { 2003 return ''; 2004 } 2005 2006 return $content; 2007 } 2008 2009 /** 2010 * Removes any invalid control characters in a text string. 2011 * 2012 * Also removes any instance of the `\0` string. 2013 * 2014 * @since 1.0.0 2015 * 2016 * @param string $content Content to filter null characters from. 2017 * @param array $options Set 'slash_zero' => 'keep' when '\0' is allowed. Default is 'remove'. 2018 * @return string Filtered content. 2019 */ 2020 function wp_kses_no_null( $content, $options = null ) { 2021 if ( ! isset( $options['slash_zero'] ) ) { 2022 $options = array( 'slash_zero' => 'remove' ); 2023 } 2024 2025 $content = preg_replace( '/[\x00-\x08\x0B\x0C\x0E-\x1F]/', '', $content ); 2026 if ( 'remove' === $options['slash_zero'] ) { 2027 $content = preg_replace( '/\\\\+0+/', '', $content ); 2028 } 2029 2030 return $content; 2031 } 2032 2033 /** 2034 * Strips slashes from in front of quotes. 2035 * 2036 * This function changes the character sequence `\"` to just `"`. It leaves all other 2037 * slashes alone. The quoting from `preg_replace(//e)` requires this. 2038 * 2039 * @since 1.0.0 2040 * 2041 * @param string $content String to strip slashes from. 2042 * @return string Fixed string with quoted slashes. 2043 */ 2044 function wp_kses_stripslashes( $content ) { 2045 return preg_replace( '%\\\\"%', '"', $content ); 2046 } 2047 2048 /** 2049 * Converts the keys of an array to lowercase. 2050 * 2051 * @since 1.0.0 2052 * 2053 * @param array $inarray Unfiltered array. 2054 * @return array Fixed array with all lowercase keys. 2055 */ 2056 function wp_kses_array_lc( $inarray ) { 2057 $outarray = array(); 2058 2059 foreach ( (array) $inarray as $inkey => $inval ) { 2060 $outkey = strtolower( $inkey ); 2061 $outarray[ $outkey ] = array(); 2062 2063 foreach ( (array) $inval as $inkey2 => $inval2 ) { 2064 $outkey2 = strtolower( $inkey2 ); 2065 $outarray[ $outkey ][ $outkey2 ] = $inval2; 2066 } 2067 } 2068 2069 return $outarray; 2070 } 2071 2072 /** 2073 * Handles parsing errors in `wp_kses_hair()`. 2074 * 2075 * The general plan is to remove everything to and including some whitespace, 2076 * but it deals with quotes and apostrophes as well. 2077 * 2078 * @since 1.0.0 2079 * 2080 * @param string $attr 2081 * @return string 2082 */ 2083 function wp_kses_html_error( $attr ) { 2084 return preg_replace( '/^("[^"]*("|$)|\'[^\']*(\'|$)|\S)*\s*/', '', $attr ); 2085 } 2086 2087 /** 2088 * Sanitizes content from bad protocols and other characters. 2089 * 2090 * This function searches for URL protocols at the beginning of the string, while 2091 * handling whitespace and HTML entities. 2092 * 2093 * @since 1.0.0 2094 * 2095 * @param string $content Content to check for bad protocols. 2096 * @param string[] $allowed_protocols Array of allowed URL protocols. 2097 * @param int $count Depth of call recursion to this function. 2098 * @return string Sanitized content. 2099 */ 2100 function wp_kses_bad_protocol_once( $content, $allowed_protocols, $count = 1 ) { 2101 $content = preg_replace( '/(�*58(?![;0-9])|�*3a(?![;a-f0-9]))/i', '$1;', $content ); 2102 $content2 = preg_split( '/:|�*58;|�*3a;|:/i', $content, 2 ); 2103 2104 if ( isset( $content2[1] ) && ! preg_match( '%/\?%', $content2[0] ) ) { 2105 $content = trim( $content2[1] ); 2106 $protocol = wp_kses_bad_protocol_once2( $content2[0], $allowed_protocols ); 2107 if ( 'feed:' === $protocol ) { 2108 if ( $count > 2 ) { 2109 return ''; 2110 } 2111 $content = wp_kses_bad_protocol_once( $content, $allowed_protocols, ++$count ); 2112 if ( empty( $content ) ) { 2113 return $content; 2114 } 2115 } 2116 $content = $protocol . $content; 2117 } 2118 2119 return $content; 2120 } 2121 2122 /** 2123 * Callback for `wp_kses_bad_protocol_once()` regular expression. 2124 * 2125 * This function processes URL protocols, checks to see if they're in the 2126 * list of allowed protocols or not, and returns different data depending 2127 * on the answer. 2128 * 2129 * @access private 2130 * @ignore 2131 * @since 1.0.0 2132 * 2133 * @param string $scheme URI scheme to check against the list of allowed protocols. 2134 * @param string[] $allowed_protocols Array of allowed URL protocols. 2135 * @return string Sanitized content. 2136 */ 2137 function wp_kses_bad_protocol_once2( $scheme, $allowed_protocols ) { 2138 $scheme = wp_kses_decode_entities( $scheme ); 2139 $scheme = preg_replace( '/\s/', '', $scheme ); 2140 $scheme = wp_kses_no_null( $scheme ); 2141 $scheme = strtolower( $scheme ); 2142 2143 $allowed = array_any( (array) $allowed_protocols, fn( $protocol ) => strtolower( $protocol ) === $scheme ); 2144 2145 if ( $allowed ) { 2146 return "$scheme:"; 2147 } else { 2148 return ''; 2149 } 2150 } 2151 2152 /** 2153 * Converts and fixes HTML entities. 2154 * 2155 * This function normalizes HTML entities. It will convert `AT&T` to the correct 2156 * `AT&T`, `:` to `:`, `&#XYZZY;` to `&#XYZZY;` and so on. 2157 * 2158 * When `$context` is set to 'xml', HTML entities are converted to their code points. For 2159 * example, `AT&T…&#XYZZY;` is converted to `AT&T…&#XYZZY;`. 2160 * 2161 * @since 1.0.0 2162 * @since 5.5.0 Added `$context` parameter. 2163 * 2164 * @param string $content Content to normalize entities. 2165 * @param string $context Context for normalization. Can be either 'html' or 'xml'. 2166 * Default 'html'. 2167 * @return string Content with normalized entities. 2168 */ 2169 function wp_kses_normalize_entities( $content, $context = 'html' ) { 2170 // Disarm all entities by converting & to & 2171 $content = str_replace( '&', '&', $content ); 2172 2173 /* 2174 * Decode any character references that are now double-encoded. 2175 * 2176 * It's important that the following normalizations happen in the correct order. 2177 * 2178 * At this point, all `&` have been transformed to `&`. Double-encoded named character 2179 * references like `&amp;` will be decoded back to their single-encoded form `&`. 2180 * 2181 * First, numeric (decimal and hexadecimal) character references must be handled so that 2182 * `&#09;` becomes `	`. If the named character references were handled first, there 2183 * would be no way to know whether the double-encoded character reference had been produced 2184 * in this function or was the original input. 2185 * 2186 * Consider the two examples, first with named entity decoding followed by numeric 2187 * entity decoding. We'll use U+002E FULL STOP (.) in our example, this table follows the 2188 * string processing from left to right: 2189 * 2190 * | Input | &-encoded | Named ref double-decoded | Numeric ref double-decoded | 2191 * | ------------ | ---------------- | ------------------------- | -------------------------- | 2192 * | `.` | `&#x2E;` | `&#x2E;` | `.` | 2193 * | `&#x2E;` | `&amp;#x2E;` | `&#x2E;` | `.` | 2194 * 2195 * Notice in the example above that different inputs result in the same result. The second case 2196 * was not normalized and produced HTML that is semantically different from the input. 2197 * 2198 * | Input | &-encoded | Numeric ref double-decoded | Named ref double-decoded | 2199 * | ------------ | ---------------- | --------------------------- | ------------------------ | 2200 * | `.` | `&#x2E;` | `.` | `.` | 2201 * | `&#x2E;` | `&amp;#x2E;` | `&amp;#x2E;` | `&#x2E;` | 2202 * 2203 * Here, each input is normalized to an appropriate output. 2204 */ 2205 $content = preg_replace_callback( '/&#(0*[1-9][0-9]{0,6});/', 'wp_kses_normalize_entities2', $content ); 2206 $content = preg_replace_callback( '/&#[Xx](0*[1-9A-Fa-f][0-9A-Fa-f]{0,5});/', 'wp_kses_normalize_entities3', $content ); 2207 if ( 'xml' === $context ) { 2208 $content = preg_replace_callback( '/&([A-Za-z]{2,8}[0-9]{0,2});/', 'wp_kses_xml_named_entities', $content ); 2209 } else { 2210 $content = preg_replace_callback( '/&([A-Za-z]{2,8}[0-9]{0,2});/', 'wp_kses_named_entities', $content ); 2211 } 2212 2213 return $content; 2214 } 2215 2216 /** 2217 * Callback for `wp_kses_normalize_entities()` regular expression. 2218 * 2219 * This function only accepts valid named entity references, which are finite, 2220 * case-sensitive, and highly scrutinized by HTML and XML validators. 2221 * 2222 * @since 3.0.0 2223 * 2224 * @global array $allowedentitynames 2225 * 2226 * @param array $matches preg_replace_callback() matches array. 2227 * @return string Correctly encoded entity. 2228 */ 2229 function wp_kses_named_entities( $matches ) { 2230 global $allowedentitynames; 2231 2232 if ( empty( $matches[1] ) ) { 2233 return ''; 2234 } 2235 2236 $i = $matches[1]; 2237 return ( ! in_array( $i, $allowedentitynames, true ) ) ? "&$i;" : "&$i;"; 2238 } 2239 2240 /** 2241 * Callback for `wp_kses_normalize_entities()` regular expression. 2242 * 2243 * This function only accepts valid named entity references, which are finite, 2244 * case-sensitive, and highly scrutinized by XML validators. HTML named entity 2245 * references are converted to their code points. 2246 * 2247 * @since 5.5.0 2248 * 2249 * @global array $allowedentitynames 2250 * @global array $allowedxmlentitynames 2251 * 2252 * @param array $matches preg_replace_callback() matches array. 2253 * @return string Correctly encoded entity. 2254 */ 2255 function wp_kses_xml_named_entities( $matches ) { 2256 global $allowedentitynames, $allowedxmlentitynames; 2257 2258 if ( empty( $matches[1] ) ) { 2259 return ''; 2260 } 2261 2262 $i = $matches[1]; 2263 2264 if ( in_array( $i, $allowedxmlentitynames, true ) ) { 2265 return "&$i;"; 2266 } elseif ( in_array( $i, $allowedentitynames, true ) ) { 2267 return html_entity_decode( "&$i;", ENT_HTML5 ); 2268 } 2269 2270 return "&$i;"; 2271 } 2272 2273 /** 2274 * Callback for `wp_kses_normalize_entities()` regular expression. 2275 * 2276 * This function helps `wp_kses_normalize_entities()` to only accept 16-bit 2277 * values and nothing more for `&#number;` entities. 2278 * 2279 * @access private 2280 * @ignore 2281 * @since 1.0.0 2282 * 2283 * @param array $matches `preg_replace_callback()` matches array. 2284 * @return string Correctly encoded entity. 2285 */ 2286 function wp_kses_normalize_entities2( $matches ) { 2287 if ( empty( $matches[1] ) ) { 2288 return ''; 2289 } 2290 2291 $i = $matches[1]; 2292 2293 if ( valid_unicode( $i ) ) { 2294 $i = str_pad( ltrim( $i, '0' ), 3, '0', STR_PAD_LEFT ); 2295 $i = "&#$i;"; 2296 } else { 2297 $i = "&#$i;"; 2298 } 2299 2300 return $i; 2301 } 2302 2303 /** 2304 * Callback for `wp_kses_normalize_entities()` for regular expression. 2305 * 2306 * This function helps `wp_kses_normalize_entities()` to only accept valid Unicode 2307 * numeric entities in hex form. 2308 * 2309 * @since 2.7.0 2310 * @access private 2311 * @ignore 2312 * 2313 * @param array $matches `preg_replace_callback()` matches array. 2314 * @return string Correctly encoded entity. 2315 */ 2316 function wp_kses_normalize_entities3( $matches ) { 2317 if ( empty( $matches[1] ) ) { 2318 return ''; 2319 } 2320 2321 $hexchars = $matches[1]; 2322 2323 return ( ! valid_unicode( hexdec( $hexchars ) ) ) ? "&#x$hexchars;" : '&#x' . ltrim( $hexchars, '0' ) . ';'; 2324 } 2325 2326 /** 2327 * Determines if a Unicode codepoint is valid. 2328 * 2329 * The definition of a valid Unicode codepoint is taken from the XML definition: 2330 * 2331 * > Characters 2332 * > 2333 * > … 2334 * > Legal characters are tab, carriage return, line feed, and the legal characters of 2335 * > Unicode and ISO/IEC 10646. 2336 * > … 2337 * > Char ::= #x9 | #xA | #xD | [#x20-#xD7FF] | [#xE000-#xFFFD] | [#x10000-#x10FFFF] 2338 * 2339 * @since 2.7.0 2340 * 2341 * @see https://www.w3.org/TR/xml/#charsets 2342 * 2343 * @param int $i Unicode codepoint. 2344 * @return bool Whether or not the codepoint is a valid Unicode codepoint. 2345 */ 2346 function valid_unicode( $i ) { 2347 $i = (int) $i; 2348 2349 return ( 2350 0x9 === $i || // U+0009 HORIZONTAL TABULATION (HT) 2351 0xA === $i || // U+000A LINE FEED (LF) 2352 0xD === $i || // U+000D CARRIAGE RETURN (CR) 2353 /* 2354 * The valid Unicode characters according to the XML specification: 2355 * 2356 * > any Unicode character, excluding the surrogate blocks, FFFE, and FFFF. 2357 */ 2358 ( 0x20 <= $i && $i <= 0xD7FF ) || 2359 ( 0xE000 <= $i && $i <= 0xFFFD ) || 2360 ( 0x10000 <= $i && $i <= 0x10FFFF ) 2361 ); 2362 } 2363 2364 /** 2365 * Converts all numeric HTML entities to their named counterparts. 2366 * 2367 * This function decodes numeric HTML entities (`A` and `A`). 2368 * It doesn't do anything with named entities like `ä`, but we don't 2369 * need them in the allowed URL protocols system anyway. 2370 * 2371 * @since 1.0.0 2372 * 2373 * @param string $content Content to change entities. 2374 * @return string Content after decoded entities. 2375 */ 2376 function wp_kses_decode_entities( $content ) { 2377 $content = preg_replace_callback( '/&#([0-9]+);/', '_wp_kses_decode_entities_chr', $content ); 2378 $content = preg_replace_callback( '/&#[Xx]([0-9A-Fa-f]+);/', '_wp_kses_decode_entities_chr_hexdec', $content ); 2379 2380 return $content; 2381 } 2382 2383 /** 2384 * Regex callback for `wp_kses_decode_entities()`. 2385 * 2386 * @since 2.9.0 2387 * @access private 2388 * @ignore 2389 * 2390 * @param array $matches preg match 2391 * @return string 2392 */ 2393 function _wp_kses_decode_entities_chr( $matches ) { 2394 return chr( $matches[1] ); 2395 } 2396 2397 /** 2398 * Regex callback for `wp_kses_decode_entities()`. 2399 * 2400 * @since 2.9.0 2401 * @access private 2402 * @ignore 2403 * 2404 * @param array $matches preg match 2405 * @return string 2406 */ 2407 function _wp_kses_decode_entities_chr_hexdec( $matches ) { 2408 return chr( hexdec( $matches[1] ) ); 2409 } 2410 2411 /** 2412 * Sanitize content with allowed HTML KSES rules. 2413 * 2414 * This function expects slashed data. 2415 * 2416 * @since 1.0.0 2417 * 2418 * @param string $data Content to filter, expected to be escaped with slashes. 2419 * @return string Filtered content. 2420 */ 2421 function wp_filter_kses( $data ) { 2422 return addslashes( wp_kses( stripslashes( $data ), current_filter() ) ); 2423 } 2424 2425 /** 2426 * Sanitize content with allowed HTML KSES rules. 2427 * 2428 * This function expects unslashed data. 2429 * 2430 * @since 2.9.0 2431 * 2432 * @param string $data Content to filter, expected to not be escaped. 2433 * @return string Filtered content. 2434 */ 2435 function wp_kses_data( $data ) { 2436 return wp_kses( $data, current_filter() ); 2437 } 2438 2439 /** 2440 * Sanitizes content for allowed HTML tags for post content. 2441 * 2442 * Post content refers to the page contents of the 'post' type and not `$_POST` 2443 * data from forms. 2444 * 2445 * This function expects slashed data. 2446 * 2447 * @since 2.0.0 2448 * 2449 * @param string $data Post content to filter, expected to be escaped with slashes. 2450 * @return string Filtered post content with allowed HTML tags and attributes intact. 2451 */ 2452 function wp_filter_post_kses( $data ) { 2453 return addslashes( wp_kses( stripslashes( $data ), 'post' ) ); 2454 } 2455 2456 /** 2457 * Sanitizes global styles user content removing unsafe rules. 2458 * 2459 * @since 5.9.0 2460 * 2461 * @param string $data Post content to filter. 2462 * @return string Filtered post content with unsafe rules removed. 2463 */ 2464 function wp_filter_global_styles_post( $data ) { 2465 $decoded_data = json_decode( wp_unslash( $data ), true ); 2466 $json_decoding_error = json_last_error(); 2467 if ( 2468 JSON_ERROR_NONE === $json_decoding_error && 2469 is_array( $decoded_data ) && 2470 isset( $decoded_data['isGlobalStylesUserThemeJSON'] ) && 2471 $decoded_data['isGlobalStylesUserThemeJSON'] 2472 ) { 2473 unset( $decoded_data['isGlobalStylesUserThemeJSON'] ); 2474 2475 $data_to_encode = WP_Theme_JSON::remove_insecure_properties( $decoded_data, 'custom' ); 2476 2477 $data_to_encode['isGlobalStylesUserThemeJSON'] = true; 2478 /** 2479 * JSON encode the data stored in post content. 2480 * Escape characters that are likely to be mangled by HTML filters: "<>&". 2481 * 2482 * This matches the escaping in {@see WP_REST_Global_Styles_Controller::prepare_item_for_database()}. 2483 */ 2484 return wp_slash( wp_json_encode( $data_to_encode, JSON_UNESCAPED_SLASHES | JSON_HEX_TAG | JSON_HEX_AMP ) ); 2485 } 2486 return $data; 2487 } 2488 2489 /** 2490 * Sanitizes content for allowed HTML tags for post content. 2491 * 2492 * Post content refers to the page contents of the 'post' type and not `$_POST` 2493 * data from forms. 2494 * 2495 * This function expects unslashed data. 2496 * 2497 * @since 2.9.0 2498 * 2499 * @param string $data Post content to filter. 2500 * @return string Filtered post content with allowed HTML tags and attributes intact. 2501 */ 2502 function wp_kses_post( $data ) { 2503 return wp_kses( $data, 'post' ); 2504 } 2505 2506 /** 2507 * Navigates through an array, object, or scalar, and sanitizes content for 2508 * allowed HTML tags for post content. 2509 * 2510 * @since 4.4.2 2511 * 2512 * @see map_deep() 2513 * 2514 * @param mixed $data The array, object, or scalar value to inspect. 2515 * @return mixed The filtered content. 2516 */ 2517 function wp_kses_post_deep( $data ) { 2518 return map_deep( $data, 'wp_kses_post' ); 2519 } 2520 2521 /** 2522 * Strips all HTML from a text string. 2523 * 2524 * This function expects slashed data. 2525 * 2526 * @since 2.1.0 2527 * 2528 * @param string $data Content to strip all HTML from. 2529 * @return string Filtered content without any HTML. 2530 */ 2531 function wp_filter_nohtml_kses( $data ) { 2532 return addslashes( wp_kses( stripslashes( $data ), 'strip' ) ); 2533 } 2534 2535 /** 2536 * Adds all KSES input form content filters. 2537 * 2538 * All hooks have default priority. The `wp_filter_kses()` function is added to 2539 * the 'pre_comment_content' and 'title_save_pre' hooks. 2540 * 2541 * The `wp_filter_post_kses()` function is added to the 'content_save_pre', 2542 * 'excerpt_save_pre', and 'content_filtered_save_pre' hooks. 2543 * 2544 * @since 2.0.0 2545 */ 2546 function kses_init_filters() { 2547 // Normal filtering. 2548 add_filter( 'title_save_pre', 'wp_filter_kses' ); 2549 2550 // Comment filtering. 2551 if ( current_user_can( 'unfiltered_html' ) ) { 2552 add_filter( 'pre_comment_content', 'wp_filter_post_kses' ); 2553 } else { 2554 add_filter( 'pre_comment_content', 'wp_filter_kses' ); 2555 } 2556 2557 // Global Styles filtering: Global Styles filters should be executed before normal post_kses HTML filters. 2558 add_filter( 'content_save_pre', 'wp_filter_global_styles_post', 9 ); 2559 add_filter( 'content_filtered_save_pre', 'wp_filter_global_styles_post', 9 ); 2560 2561 // Post filtering. 2562 add_filter( 'content_save_pre', 'wp_filter_post_kses' ); 2563 add_filter( 'excerpt_save_pre', 'wp_filter_post_kses' ); 2564 add_filter( 'content_filtered_save_pre', 'wp_filter_post_kses' ); 2565 } 2566 2567 /** 2568 * Removes all KSES input form content filters. 2569 * 2570 * A quick procedural method to removing all of the filters that KSES uses for 2571 * content in WordPress Loop. 2572 * 2573 * Does not remove the `kses_init()` function from {@see 'init'} hook (priority is 2574 * default). Also does not remove `kses_init()` function from {@see 'set_current_user'} 2575 * hook (priority is also default). 2576 * 2577 * @since 2.0.6 2578 */ 2579 function kses_remove_filters() { 2580 // Normal filtering. 2581 remove_filter( 'title_save_pre', 'wp_filter_kses' ); 2582 2583 // Comment filtering. 2584 remove_filter( 'pre_comment_content', 'wp_filter_post_kses' ); 2585 remove_filter( 'pre_comment_content', 'wp_filter_kses' ); 2586 2587 // Global Styles filtering. 2588 remove_filter( 'content_save_pre', 'wp_filter_global_styles_post', 9 ); 2589 remove_filter( 'content_filtered_save_pre', 'wp_filter_global_styles_post', 9 ); 2590 2591 // Post filtering. 2592 remove_filter( 'content_save_pre', 'wp_filter_post_kses' ); 2593 remove_filter( 'excerpt_save_pre', 'wp_filter_post_kses' ); 2594 remove_filter( 'content_filtered_save_pre', 'wp_filter_post_kses' ); 2595 } 2596 2597 /** 2598 * Sets up most of the KSES filters for input form content. 2599 * 2600 * First removes all of the KSES filters in case the current user does not need 2601 * to have KSES filter the content. If the user does not have `unfiltered_html` 2602 * capability, then KSES filters are added. 2603 * 2604 * @since 2.0.0 2605 */ 2606 function kses_init() { 2607 kses_remove_filters(); 2608 2609 if ( ! current_user_can( 'unfiltered_html' ) ) { 2610 kses_init_filters(); 2611 } 2612 } 2613 2614 /** 2615 * Filters an inline style attribute and removes disallowed rules. 2616 * 2617 * @since 2.8.1 2618 * @since 4.4.0 Added support for `min-height`, `max-height`, `min-width`, and `max-width`. 2619 * @since 4.6.0 Added support for `list-style-type`. 2620 * @since 5.0.0 Added support for `background-image`. 2621 * @since 5.1.0 Added support for `text-transform`. 2622 * @since 5.2.0 Added support for `background-position` and `grid-template-columns`. 2623 * @since 5.3.0 Added support for `grid`, `flex` and `column` layout properties. 2624 * Extended `background-*` support for individual properties. 2625 * @since 5.3.1 Added support for gradient backgrounds. 2626 * @since 5.7.1 Added support for `object-position`. 2627 * @since 5.8.0 Added support for `calc()` and `var()` values. 2628 * @since 6.1.0 Added support for `min()`, `max()`, `minmax()`, `clamp()`, 2629 * nested `var()` values, and assigning values to CSS variables. 2630 * Added support for `object-fit`, `gap`, `column-gap`, `row-gap`, and `flex-wrap`. 2631 * Extended `margin-*` and `padding-*` support for logical properties. 2632 * @since 6.2.0 Added support for `aspect-ratio`, `position`, `top`, `right`, `bottom`, `left`, 2633 * and `z-index` CSS properties. 2634 * @since 6.3.0 Extended support for `filter` to accept a URL and added support for repeat(). 2635 * Added support for `box-shadow`. 2636 * @since 6.4.0 Added support for `writing-mode`. 2637 * @since 6.5.0 Added support for `background-repeat`. 2638 * @since 6.6.0 Added support for `grid-column`, `grid-row`, and `container-type`. 2639 * @since 6.9.0 Added support for `white-space`. 2640 * @since 7.1.0 Extended gradient support to allow any single-level nested function. 2641 * 2642 * @param string $css A string of CSS rules, decoded from an HTML `style` attribute. 2643 * @param string $deprecated Not used. 2644 * @return string Filtered string of CSS rules, needing HTML escaping before sending back to a `style` attribute. 2645 */ 2646 function safecss_filter_attr( $css, $deprecated = '' ) { 2647 if ( ! empty( $deprecated ) ) { 2648 _deprecated_argument( __FUNCTION__, '2.8.1' ); // Never implemented. 2649 } 2650 2651 $css = wp_kses_no_null( $css ); 2652 $css = str_replace( array( "\n", "\r", "\t" ), '', $css ); 2653 2654 $allowed_protocols = wp_allowed_protocols(); 2655 2656 /** @todo Parse enough CSS to split rules without breaking on things like quoted strings. */ 2657 $css_array = explode( ';', trim( $css ) ); 2658 2659 /** 2660 * Filters the list of allowed CSS attributes. 2661 * 2662 * @since 2.8.1 2663 * @since 7.1.0 Added support for SVG presentation attributes. 2664 * 2665 * @param string[] $attr Array of allowed CSS attributes. 2666 */ 2667 $allowed_attr = apply_filters( 2668 'safe_style_css', 2669 array( 2670 'background', 2671 'background-color', 2672 'background-image', 2673 'background-position', 2674 'background-repeat', 2675 'background-size', 2676 'background-attachment', 2677 'background-blend-mode', 2678 2679 'border', 2680 'border-radius', 2681 'border-width', 2682 'border-color', 2683 'border-style', 2684 'border-right', 2685 'border-right-color', 2686 'border-right-style', 2687 'border-right-width', 2688 'border-bottom', 2689 'border-bottom-color', 2690 'border-bottom-left-radius', 2691 'border-bottom-right-radius', 2692 'border-bottom-style', 2693 'border-bottom-width', 2694 'border-bottom-right-radius', 2695 'border-bottom-left-radius', 2696 'border-left', 2697 'border-left-color', 2698 'border-left-style', 2699 'border-left-width', 2700 'border-top', 2701 'border-top-color', 2702 'border-top-left-radius', 2703 'border-top-right-radius', 2704 'border-top-style', 2705 'border-top-width', 2706 'border-top-left-radius', 2707 'border-top-right-radius', 2708 2709 'border-spacing', 2710 'border-collapse', 2711 'caption-side', 2712 2713 'columns', 2714 'column-count', 2715 'column-fill', 2716 'column-gap', 2717 'column-rule', 2718 'column-span', 2719 'column-width', 2720 2721 'display', 2722 2723 'color', 2724 'filter', 2725 'font', 2726 'font-family', 2727 'font-size', 2728 'font-style', 2729 'font-variant', 2730 'font-weight', 2731 'letter-spacing', 2732 'line-height', 2733 'text-align', 2734 'text-decoration', 2735 'text-indent', 2736 'text-transform', 2737 'white-space', 2738 2739 'height', 2740 'min-height', 2741 'max-height', 2742 2743 'width', 2744 'min-width', 2745 'max-width', 2746 2747 'margin', 2748 'margin-right', 2749 'margin-bottom', 2750 'margin-left', 2751 'margin-top', 2752 'margin-block-start', 2753 'margin-block-end', 2754 'margin-inline-start', 2755 'margin-inline-end', 2756 2757 'padding', 2758 'padding-right', 2759 'padding-bottom', 2760 'padding-left', 2761 'padding-top', 2762 'padding-block-start', 2763 'padding-block-end', 2764 'padding-inline-start', 2765 'padding-inline-end', 2766 2767 'flex', 2768 'flex-basis', 2769 'flex-direction', 2770 'flex-flow', 2771 'flex-grow', 2772 'flex-shrink', 2773 'flex-wrap', 2774 2775 'gap', 2776 'column-gap', 2777 'row-gap', 2778 2779 'grid-template-columns', 2780 'grid-auto-columns', 2781 'grid-column-start', 2782 'grid-column-end', 2783 'grid-column', 2784 'grid-column-gap', 2785 'grid-template-rows', 2786 'grid-auto-rows', 2787 'grid-row-start', 2788 'grid-row-end', 2789 'grid-row', 2790 'grid-row-gap', 2791 'grid-gap', 2792 2793 'justify-content', 2794 'justify-items', 2795 'justify-self', 2796 'align-content', 2797 'align-items', 2798 'align-self', 2799 2800 'clear', 2801 'cursor', 2802 'direction', 2803 'float', 2804 'list-style-type', 2805 'object-fit', 2806 'object-position', 2807 'opacity', 2808 'overflow', 2809 'vertical-align', 2810 'writing-mode', 2811 2812 'position', 2813 'top', 2814 'right', 2815 'bottom', 2816 'left', 2817 'z-index', 2818 'box-shadow', 2819 'aspect-ratio', 2820 'container-type', 2821 2822 'fill', 2823 'fill-opacity', 2824 'fill-rule', 2825 2826 'stroke', 2827 'stroke-dasharray', 2828 'stroke-dashoffset', 2829 'stroke-linecap', 2830 'stroke-linejoin', 2831 'stroke-miterlimit', 2832 'stroke-opacity', 2833 'stroke-width', 2834 2835 'color-interpolation', 2836 'color-interpolation-filters', 2837 'paint-order', 2838 'stop-color', 2839 'stop-opacity', 2840 'flood-color', 2841 'flood-opacity', 2842 'lighting-color', 2843 2844 'marker', 2845 'marker-end', 2846 'marker-mid', 2847 'marker-start', 2848 2849 'clip-path', 2850 'clip-rule', 2851 'mask', 2852 'mask-type', 2853 2854 'cx', 2855 'cy', 2856 'r', 2857 'rx', 2858 'ry', 2859 'x', 2860 'y', 2861 'd', 2862 2863 'alignment-baseline', 2864 'baseline-shift', 2865 'dominant-baseline', 2866 'glyph-orientation-horizontal', 2867 'glyph-orientation-vertical', 2868 'text-anchor', 2869 'unicode-bidi', 2870 'word-spacing', 2871 2872 'font-size-adjust', 2873 'font-stretch', 2874 2875 'color-rendering', 2876 'image-rendering', 2877 'shape-rendering', 2878 'text-rendering', 2879 'vector-effect', 2880 2881 'transform', 2882 'transform-origin', 2883 2884 'pointer-events', 2885 'visibility', 2886 2887 // Custom CSS properties. 2888 '--*', 2889 ) 2890 ); 2891 2892 /* 2893 * CSS attributes that accept URL data types. 2894 * 2895 * This is in accordance to the CSS spec and unrelated to 2896 * the sub-set of supported attributes above. 2897 * 2898 * See: https://developer.mozilla.org/en-US/docs/Web/CSS/url 2899 */ 2900 $css_url_data_types = array( 2901 'background', 2902 'background-image', 2903 2904 'cursor', 2905 'filter', 2906 2907 'list-style', 2908 'list-style-image', 2909 ); 2910 2911 /* 2912 * CSS attributes that accept gradient data types. 2913 * 2914 */ 2915 $css_gradient_data_types = array( 2916 'background', 2917 'background-image', 2918 ); 2919 2920 if ( empty( $allowed_attr ) ) { 2921 return $css; 2922 } 2923 2924 $css = ''; 2925 foreach ( $css_array as $css_item ) { 2926 if ( '' === $css_item ) { 2927 continue; 2928 } 2929 2930 $css_item = trim( $css_item ); 2931 $css_test_string = $css_item; 2932 $found = false; 2933 $url_attr = false; 2934 $gradient_attr = false; 2935 $is_custom_var = false; 2936 2937 if ( ! str_contains( $css_item, ':' ) ) { 2938 $found = true; 2939 } else { 2940 $parts = explode( ':', $css_item, 2 ); 2941 $css_selector = trim( $parts[0] ); 2942 2943 // Allow assigning values to CSS variables. 2944 if ( in_array( '--*', $allowed_attr, true ) && preg_match( '/^--[a-zA-Z0-9-_]+$/', $css_selector ) ) { 2945 $allowed_attr[] = $css_selector; 2946 $is_custom_var = true; 2947 } 2948 2949 if ( in_array( $css_selector, $allowed_attr, true ) ) { 2950 $found = true; 2951 $url_attr = in_array( $css_selector, $css_url_data_types, true ); 2952 $gradient_attr = in_array( $css_selector, $css_gradient_data_types, true ); 2953 } 2954 2955 if ( $is_custom_var ) { 2956 $css_value = trim( $parts[1] ); 2957 $url_attr = str_starts_with( $css_value, 'url(' ); 2958 $gradient_attr = str_contains( $css_value, '-gradient(' ); 2959 } 2960 } 2961 2962 if ( $found && $url_attr ) { 2963 // Simplified: matches the sequence `url(*)`. 2964 preg_match_all( '/url\([^)]+\)/', $parts[1], $url_matches ); 2965 2966 foreach ( $url_matches[0] as $url_match ) { 2967 // Clean up the URL from each of the matches above. 2968 preg_match( '/^url\(\s*([\'\"]?)(.*)(\g1)\s*\)$/', $url_match, $url_pieces ); 2969 2970 if ( empty( $url_pieces[2] ) ) { 2971 $found = false; 2972 break; 2973 } 2974 2975 $url = trim( $url_pieces[2] ); 2976 2977 if ( empty( $url ) || wp_kses_bad_protocol( $url, $allowed_protocols ) !== $url ) { 2978 $found = false; 2979 break; 2980 } else { 2981 // Remove the whole `url(*)` bit that was matched above from the CSS. 2982 $css_test_string = str_replace( $url_match, '', $css_test_string ); 2983 } 2984 } 2985 } 2986 2987 if ( $found && $gradient_attr ) { 2988 /* 2989 * Match every `*-gradient()` in the value, allowing one level of nested functions 2990 * (e.g. rgb(), hsl(), var()). Matching each occurrence, rather than requiring the 2991 * whole value to be a single gradient, lets a gradient combine with a url() image. 2992 */ 2993 preg_match_all( '/(?:repeating-)?(?:linear|radial|conic)-gradient\((?:[^()]|\([^()]*\))*\)/', $css_test_string, $gradient_matches ); 2994 2995 foreach ( $gradient_matches[0] as $gradient_match ) { 2996 // Remove each `gradient()` bit that was matched above from the CSS. 2997 $css_test_string = str_replace( $gradient_match, '', $css_test_string ); 2998 } 2999 } 3000 3001 if ( $found ) { 3002 /* 3003 * Allow CSS functions like var(), calc(), etc. by removing them from the test string. 3004 * Nested functions and parentheses are also removed, so long as the parentheses are balanced. 3005 */ 3006 $css_test_string = preg_replace( 3007 '/\b(?:var|calc|min|max|minmax|clamp|repeat)(\((?:[^()]|(?1))*\))/', 3008 '', 3009 $css_test_string 3010 ); 3011 3012 /* 3013 * Disallow CSS containing \ ( & } = or comments, except for within url(), var(), calc(), etc. 3014 * which were removed from the test string above. 3015 */ 3016 $allow_css = ! preg_match( '%[\\\(&=}]|/\*%', $css_test_string ); 3017 3018 /** 3019 * Filters the check for unsafe CSS in `safecss_filter_attr`. 3020 * 3021 * Enables developers to determine whether a section of CSS should be allowed or discarded. 3022 * By default, the value will be false if the part contains \ ( & } = or comments. 3023 * Return true to allow the CSS part to be included in the output. 3024 * 3025 * @since 5.5.0 3026 * 3027 * @param bool $allow_css Whether the CSS in the test string is considered safe. 3028 * @param string $css_test_string The CSS string to test. 3029 */ 3030 $allow_css = apply_filters( 'safecss_filter_attr_allow_css', $allow_css, $css_test_string ); 3031 3032 // Only add the CSS part if it passes the regex check. 3033 if ( $allow_css ) { 3034 if ( '' !== $css ) { 3035 $css .= ';'; 3036 } 3037 3038 $css .= $css_item; 3039 } 3040 } 3041 } 3042 3043 return $css; 3044 } 3045 3046 /** 3047 * Helper function to add global attributes to a tag in the allowed HTML list. 3048 * 3049 * @since 3.5.0 3050 * @since 5.0.0 Added support for `data-*` wildcard attributes. 3051 * @since 6.0.0 Added `dir`, `lang`, and `xml:lang` to global attributes. 3052 * @since 6.3.0 Added `aria-controls`, `aria-current`, and `aria-expanded` attributes. 3053 * @since 6.4.0 Added `aria-live` and `hidden` attributes. 3054 * @since 7.1.0 Added `tabindex` attribute. 3055 * 3056 * @access private 3057 * @ignore 3058 * 3059 * @param array $value An array of attributes. 3060 * @return array The array of attributes with global attributes added. 3061 */ 3062 function _wp_add_global_attributes( $value ) { 3063 $global_attributes = array( 3064 'aria-controls' => true, 3065 'aria-current' => true, 3066 'aria-describedby' => true, 3067 'aria-details' => true, 3068 'aria-expanded' => true, 3069 'aria-hidden' => true, 3070 'aria-label' => true, 3071 'aria-labelledby' => true, 3072 'aria-live' => true, 3073 'class' => true, 3074 'data-*' => true, 3075 'dir' => true, 3076 'hidden' => true, 3077 'id' => true, 3078 'lang' => true, 3079 'style' => true, 3080 'tabindex' => true, 3081 'title' => true, 3082 'role' => true, 3083 'xml:lang' => true, 3084 ); 3085 3086 if ( true === $value ) { 3087 $value = array(); 3088 } 3089 3090 if ( is_array( $value ) ) { 3091 return array_merge( $value, $global_attributes ); 3092 } 3093 3094 return $value; 3095 } 3096 3097 /** 3098 * Helper function to check if this is a safe PDF URL. 3099 * 3100 * @since 5.9.0 3101 * @access private 3102 * @ignore 3103 * 3104 * @param string $url The URL to check. 3105 * @return bool True if the URL is safe, false otherwise. 3106 */ 3107 function _wp_kses_allow_pdf_objects( $url ) { 3108 // We're not interested in URLs that contain query strings or fragments. 3109 if ( str_contains( $url, '?' ) || str_contains( $url, '#' ) ) { 3110 return false; 3111 } 3112 3113 // If it doesn't have a PDF extension, it's not safe. 3114 if ( ! str_ends_with( $url, '.pdf' ) ) { 3115 return false; 3116 } 3117 3118 // If the URL host matches the current site's media URL, it's safe. 3119 $upload_info = wp_upload_dir( null, false ); 3120 $parsed_url = wp_parse_url( $upload_info['url'] ); 3121 $upload_host = $parsed_url['host'] ?? ''; 3122 $upload_port = isset( $parsed_url['port'] ) ? ':' . $parsed_url['port'] : ''; 3123 3124 if ( str_starts_with( $url, "http://$upload_host$upload_port/" ) 3125 || str_starts_with( $url, "https://$upload_host$upload_port/" ) 3126 ) { 3127 return true; 3128 } 3129 3130 return false; 3131 }
title
Description
Body
title
Description
Body
title
Description
Body
title
Body
| Generated : Tue Jul 28 08:20:19 2026 | Cross-referenced by PHPXref |