Add support for Number grouping(commafy) based on CLDR number grouping patterns like...
[lhc/web/wiklou.git] / includes / Sanitizer.php
index b702188..227fa7c 100644 (file)
@@ -2,7 +2,7 @@
 /**
  * XHTML sanitizer for MediaWiki
  *
- * Copyright (C) 2002-2005 Brion Vibber <brion@pobox.com> et al
+ * Copyright © 2002-2005 Brion Vibber <brion@pobox.com> et al
  * http://www.mediawiki.org/
  *
  * This program is free software; you can redistribute it and/or modify
  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  * http://www.gnu.org/copyleft/gpl.html
  *
- * @addtogroup Parser
+ * @file
+ * @ingroup Parser
  */
 
 /**
- * Regular expression to match various types of character references in
- * Sanitizer::normalizeCharReferences and Sanitizer::decodeCharReferences
+ * XHTML sanitizer for MediaWiki
+ * @ingroup Parser
  */
-define( 'MW_CHAR_REFS_REGEX',
-       '/&([A-Za-z0-9]+);
-        |&\#([0-9]+);
-        |&\#x([0-9A-Za-z]+);
-        |&\#X([0-9A-Za-z]+);
-        |(&)/x' );
+class Sanitizer {
+       /**
+        * Regular expression to match various types of character references in
+        * Sanitizer::normalizeCharReferences and Sanitizer::decodeCharReferences
+        */
+       const CHAR_REFS_REGEX = 
+               '/&([A-Za-z0-9\x80-\xff]+);
+                |&\#([0-9]+);
+                |&\#[xX]([0-9A-Fa-f]+);
+                |(&)/x';
 
-/**
- * Regular expression to match HTML/XML attribute pairs within a tag.
- * Allows some... latitude.
- * Used in Sanitizer::fixTagAttributes and Sanitizer::decodeTagAttributes
- */
-$attrib = '[A-Za-z0-9]';
-$space = '[\x09\x0a\x0d\x20]';
-define( 'MW_ATTRIBS_REGEX',
-       "/(?:^|$space)($attrib+)
-         ($space*=$space*
-               (?:
-                # The attribute value: quoted or alone
-                 \"([^<\"]*)\"
-                | '([^<']*)'
-                |  ([a-zA-Z0-9!#$%&()*,\\-.\\/:;<>?@[\\]^_`{|}~]+)
-                |  (\#[0-9a-fA-F]+) # Technically wrong, but lots of
-                                                        # colors are specified like this.
-                                                        # We'll be normalizing it.
-               )
-          )?(?=$space|\$)/sx" );
+       /**
+        * Blacklist for evil uris like javascript:
+        * WARNING: DO NOT use this in any place that actually requires blacklisting
+        * for security reasons. There are NUMEROUS[1] ways to bypass blacklisting, the
+        * only way to be secure from javascript: uri based xss vectors is to whitelist
+        * things that you know are safe and deny everything else.
+        * [1]: http://ha.ckers.org/xss.html
+        */
+       const EVIL_URI_PATTERN = '!(^|\s|\*/\s*)(javascript|vbscript)([^\w]|$)!i';
+       const XMLNS_ATTRIBUTE_PATTERN = "/^xmlns:[:A-Z_a-z-.0-9]+$/";
 
-/**
- * List of all named character entities defined in HTML 4.01
- * http://www.w3.org/TR/html4/sgml/entities.html
- * @private
- */
-global $wgHtmlEntities;
-$wgHtmlEntities = array(
-       'Aacute'   => 193,
-       'aacute'   => 225,
-       'Acirc'    => 194,
-       'acirc'    => 226,
-       'acute'    => 180,
-       'AElig'    => 198,
-       'aelig'    => 230,
-       'Agrave'   => 192,
-       'agrave'   => 224,
-       'alefsym'  => 8501,
-       'Alpha'    => 913,
-       'alpha'    => 945,
-       'amp'      => 38,
-       'and'      => 8743,
-       'ang'      => 8736,
-       'Aring'    => 197,
-       'aring'    => 229,
-       'asymp'    => 8776,
-       'Atilde'   => 195,
-       'atilde'   => 227,
-       'Auml'     => 196,
-       'auml'     => 228,
-       'bdquo'    => 8222,
-       'Beta'     => 914,
-       'beta'     => 946,
-       'brvbar'   => 166,
-       'bull'     => 8226,
-       'cap'      => 8745,
-       'Ccedil'   => 199,
-       'ccedil'   => 231,
-       'cedil'    => 184,
-       'cent'     => 162,
-       'Chi'      => 935,
-       'chi'      => 967,
-       'circ'     => 710,
-       'clubs'    => 9827,
-       'cong'     => 8773,
-       'copy'     => 169,
-       'crarr'    => 8629,
-       'cup'      => 8746,
-       'curren'   => 164,
-       'dagger'   => 8224,
-       'Dagger'   => 8225,
-       'darr'     => 8595,
-       'dArr'     => 8659,
-       'deg'      => 176,
-       'Delta'    => 916,
-       'delta'    => 948,
-       'diams'    => 9830,
-       'divide'   => 247,
-       'Eacute'   => 201,
-       'eacute'   => 233,
-       'Ecirc'    => 202,
-       'ecirc'    => 234,
-       'Egrave'   => 200,
-       'egrave'   => 232,
-       'empty'    => 8709,
-       'emsp'     => 8195,
-       'ensp'     => 8194,
-       'Epsilon'  => 917,
-       'epsilon'  => 949,
-       'equiv'    => 8801,
-       'Eta'      => 919,
-       'eta'      => 951,
-       'ETH'      => 208,
-       'eth'      => 240,
-       'Euml'     => 203,
-       'euml'     => 235,
-       'euro'     => 8364,
-       'exist'    => 8707,
-       'fnof'     => 402,
-       'forall'   => 8704,
-       'frac12'   => 189,
-       'frac14'   => 188,
-       'frac34'   => 190,
-       'frasl'    => 8260,
-       'Gamma'    => 915,
-       'gamma'    => 947,
-       'ge'       => 8805,
-       'gt'       => 62,
-       'harr'     => 8596,
-       'hArr'     => 8660,
-       'hearts'   => 9829,
-       'hellip'   => 8230,
-       'Iacute'   => 205,
-       'iacute'   => 237,
-       'Icirc'    => 206,
-       'icirc'    => 238,
-       'iexcl'    => 161,
-       'Igrave'   => 204,
-       'igrave'   => 236,
-       'image'    => 8465,
-       'infin'    => 8734,
-       'int'      => 8747,
-       'Iota'     => 921,
-       'iota'     => 953,
-       'iquest'   => 191,
-       'isin'     => 8712,
-       'Iuml'     => 207,
-       'iuml'     => 239,
-       'Kappa'    => 922,
-       'kappa'    => 954,
-       'Lambda'   => 923,
-       'lambda'   => 955,
-       'lang'     => 9001,
-       'laquo'    => 171,
-       'larr'     => 8592,
-       'lArr'     => 8656,
-       'lceil'    => 8968,
-       'ldquo'    => 8220,
-       'le'       => 8804,
-       'lfloor'   => 8970,
-       'lowast'   => 8727,
-       'loz'      => 9674,
-       'lrm'      => 8206,
-       'lsaquo'   => 8249,
-       'lsquo'    => 8216,
-       'lt'       => 60,
-       'macr'     => 175,
-       'mdash'    => 8212,
-       'micro'    => 181,
-       'middot'   => 183,
-       'minus'    => 8722,
-       'Mu'       => 924,
-       'mu'       => 956,
-       'nabla'    => 8711,
-       'nbsp'     => 160,
-       'ndash'    => 8211,
-       'ne'       => 8800,
-       'ni'       => 8715,
-       'not'      => 172,
-       'notin'    => 8713,
-       'nsub'     => 8836,
-       'Ntilde'   => 209,
-       'ntilde'   => 241,
-       'Nu'       => 925,
-       'nu'       => 957,
-       'Oacute'   => 211,
-       'oacute'   => 243,
-       'Ocirc'    => 212,
-       'ocirc'    => 244,
-       'OElig'    => 338,
-       'oelig'    => 339,
-       'Ograve'   => 210,
-       'ograve'   => 242,
-       'oline'    => 8254,
-       'Omega'    => 937,
-       'omega'    => 969,
-       'Omicron'  => 927,
-       'omicron'  => 959,
-       'oplus'    => 8853,
-       'or'       => 8744,
-       'ordf'     => 170,
-       'ordm'     => 186,
-       'Oslash'   => 216,
-       'oslash'   => 248,
-       'Otilde'   => 213,
-       'otilde'   => 245,
-       'otimes'   => 8855,
-       'Ouml'     => 214,
-       'ouml'     => 246,
-       'para'     => 182,
-       'part'     => 8706,
-       'permil'   => 8240,
-       'perp'     => 8869,
-       'Phi'      => 934,
-       'phi'      => 966,
-       'Pi'       => 928,
-       'pi'       => 960,
-       'piv'      => 982,
-       'plusmn'   => 177,
-       'pound'    => 163,
-       'prime'    => 8242,
-       'Prime'    => 8243,
-       'prod'     => 8719,
-       'prop'     => 8733,
-       'Psi'      => 936,
-       'psi'      => 968,
-       'quot'     => 34,
-       'radic'    => 8730,
-       'rang'     => 9002,
-       'raquo'    => 187,
-       'rarr'     => 8594,
-       'rArr'     => 8658,
-       'rceil'    => 8969,
-       'rdquo'    => 8221,
-       'real'     => 8476,
-       'reg'      => 174,
-       'rfloor'   => 8971,
-       'Rho'      => 929,
-       'rho'      => 961,
-       'rlm'      => 8207,
-       'rsaquo'   => 8250,
-       'rsquo'    => 8217,
-       'sbquo'    => 8218,
-       'Scaron'   => 352,
-       'scaron'   => 353,
-       'sdot'     => 8901,
-       'sect'     => 167,
-       'shy'      => 173,
-       'Sigma'    => 931,
-       'sigma'    => 963,
-       'sigmaf'   => 962,
-       'sim'      => 8764,
-       'spades'   => 9824,
-       'sub'      => 8834,
-       'sube'     => 8838,
-       'sum'      => 8721,
-       'sup'      => 8835,
-       'sup1'     => 185,
-       'sup2'     => 178,
-       'sup3'     => 179,
-       'supe'     => 8839,
-       'szlig'    => 223,
-       'Tau'      => 932,
-       'tau'      => 964,
-       'there4'   => 8756,
-       'Theta'    => 920,
-       'theta'    => 952,
-       'thetasym' => 977,
-       'thinsp'   => 8201,
-       'THORN'    => 222,
-       'thorn'    => 254,
-       'tilde'    => 732,
-       'times'    => 215,
-       'trade'    => 8482,
-       'Uacute'   => 218,
-       'uacute'   => 250,
-       'uarr'     => 8593,
-       'uArr'     => 8657,
-       'Ucirc'    => 219,
-       'ucirc'    => 251,
-       'Ugrave'   => 217,
-       'ugrave'   => 249,
-       'uml'      => 168,
-       'upsih'    => 978,
-       'Upsilon'  => 933,
-       'upsilon'  => 965,
-       'Uuml'     => 220,
-       'uuml'     => 252,
-       'weierp'   => 8472,
-       'Xi'       => 926,
-       'xi'       => 958,
-       'Yacute'   => 221,
-       'yacute'   => 253,
-       'yen'      => 165,
-       'Yuml'     => 376,
-       'yuml'     => 255,
-       'Zeta'     => 918,
-       'zeta'     => 950,
-       'zwj'      => 8205,
-       'zwnj'     => 8204 );
+       /**
+        * List of all named character entities defined in HTML 4.01
+        * http://www.w3.org/TR/html4/sgml/entities.html
+        * As well as &apos; which is only defined starting in XHTML1.
+        * @private
+        */
+       static $htmlEntities = array(
+               'Aacute'   => 193,
+               'aacute'   => 225,
+               'Acirc'    => 194,
+               'acirc'    => 226,
+               'acute'    => 180,
+               'AElig'    => 198,
+               'aelig'    => 230,
+               'Agrave'   => 192,
+               'agrave'   => 224,
+               'alefsym'  => 8501,
+               'Alpha'    => 913,
+               'alpha'    => 945,
+               'amp'      => 38,
+               'and'      => 8743,
+               'ang'      => 8736,
+               'apos'     => 39, // New in XHTML & HTML 5; avoid in output for compatibility with IE.
+               'Aring'    => 197,
+               'aring'    => 229,
+               'asymp'    => 8776,
+               'Atilde'   => 195,
+               'atilde'   => 227,
+               'Auml'     => 196,
+               'auml'     => 228,
+               'bdquo'    => 8222,
+               'Beta'     => 914,
+               'beta'     => 946,
+               'brvbar'   => 166,
+               'bull'     => 8226,
+               'cap'      => 8745,
+               'Ccedil'   => 199,
+               'ccedil'   => 231,
+               'cedil'    => 184,
+               'cent'     => 162,
+               'Chi'      => 935,
+               'chi'      => 967,
+               'circ'     => 710,
+               'clubs'    => 9827,
+               'cong'     => 8773,
+               'copy'     => 169,
+               'crarr'    => 8629,
+               'cup'      => 8746,
+               'curren'   => 164,
+               'dagger'   => 8224,
+               'Dagger'   => 8225,
+               'darr'     => 8595,
+               'dArr'     => 8659,
+               'deg'      => 176,
+               'Delta'    => 916,
+               'delta'    => 948,
+               'diams'    => 9830,
+               'divide'   => 247,
+               'Eacute'   => 201,
+               'eacute'   => 233,
+               'Ecirc'    => 202,
+               'ecirc'    => 234,
+               'Egrave'   => 200,
+               'egrave'   => 232,
+               'empty'    => 8709,
+               'emsp'     => 8195,
+               'ensp'     => 8194,
+               'Epsilon'  => 917,
+               'epsilon'  => 949,
+               'equiv'    => 8801,
+               'Eta'      => 919,
+               'eta'      => 951,
+               'ETH'      => 208,
+               'eth'      => 240,
+               'Euml'     => 203,
+               'euml'     => 235,
+               'euro'     => 8364,
+               'exist'    => 8707,
+               'fnof'     => 402,
+               'forall'   => 8704,
+               'frac12'   => 189,
+               'frac14'   => 188,
+               'frac34'   => 190,
+               'frasl'    => 8260,
+               'Gamma'    => 915,
+               'gamma'    => 947,
+               'ge'       => 8805,
+               'gt'       => 62,
+               'harr'     => 8596,
+               'hArr'     => 8660,
+               'hearts'   => 9829,
+               'hellip'   => 8230,
+               'Iacute'   => 205,
+               'iacute'   => 237,
+               'Icirc'    => 206,
+               'icirc'    => 238,
+               'iexcl'    => 161,
+               'Igrave'   => 204,
+               'igrave'   => 236,
+               'image'    => 8465,
+               'infin'    => 8734,
+               'int'      => 8747,
+               'Iota'     => 921,
+               'iota'     => 953,
+               'iquest'   => 191,
+               'isin'     => 8712,
+               'Iuml'     => 207,
+               'iuml'     => 239,
+               'Kappa'    => 922,
+               'kappa'    => 954,
+               'Lambda'   => 923,
+               'lambda'   => 955,
+               'lang'     => 9001,
+               'laquo'    => 171,
+               'larr'     => 8592,
+               'lArr'     => 8656,
+               'lceil'    => 8968,
+               'ldquo'    => 8220,
+               'le'       => 8804,
+               'lfloor'   => 8970,
+               'lowast'   => 8727,
+               'loz'      => 9674,
+               'lrm'      => 8206,
+               'lsaquo'   => 8249,
+               'lsquo'    => 8216,
+               'lt'       => 60,
+               'macr'     => 175,
+               'mdash'    => 8212,
+               'micro'    => 181,
+               'middot'   => 183,
+               'minus'    => 8722,
+               'Mu'       => 924,
+               'mu'       => 956,
+               'nabla'    => 8711,
+               'nbsp'     => 160,
+               'ndash'    => 8211,
+               'ne'       => 8800,
+               'ni'       => 8715,
+               'not'      => 172,
+               'notin'    => 8713,
+               'nsub'     => 8836,
+               'Ntilde'   => 209,
+               'ntilde'   => 241,
+               'Nu'       => 925,
+               'nu'       => 957,
+               'Oacute'   => 211,
+               'oacute'   => 243,
+               'Ocirc'    => 212,
+               'ocirc'    => 244,
+               'OElig'    => 338,
+               'oelig'    => 339,
+               'Ograve'   => 210,
+               'ograve'   => 242,
+               'oline'    => 8254,
+               'Omega'    => 937,
+               'omega'    => 969,
+               'Omicron'  => 927,
+               'omicron'  => 959,
+               'oplus'    => 8853,
+               'or'       => 8744,
+               'ordf'     => 170,
+               'ordm'     => 186,
+               'Oslash'   => 216,
+               'oslash'   => 248,
+               'Otilde'   => 213,
+               'otilde'   => 245,
+               'otimes'   => 8855,
+               'Ouml'     => 214,
+               'ouml'     => 246,
+               'para'     => 182,
+               'part'     => 8706,
+               'permil'   => 8240,
+               'perp'     => 8869,
+               'Phi'      => 934,
+               'phi'      => 966,
+               'Pi'       => 928,
+               'pi'       => 960,
+               'piv'      => 982,
+               'plusmn'   => 177,
+               'pound'    => 163,
+               'prime'    => 8242,
+               'Prime'    => 8243,
+               'prod'     => 8719,
+               'prop'     => 8733,
+               'Psi'      => 936,
+               'psi'      => 968,
+               'quot'     => 34,
+               'radic'    => 8730,
+               'rang'     => 9002,
+               'raquo'    => 187,
+               'rarr'     => 8594,
+               'rArr'     => 8658,
+               'rceil'    => 8969,
+               'rdquo'    => 8221,
+               'real'     => 8476,
+               'reg'      => 174,
+               'rfloor'   => 8971,
+               'Rho'      => 929,
+               'rho'      => 961,
+               'rlm'      => 8207,
+               'rsaquo'   => 8250,
+               'rsquo'    => 8217,
+               'sbquo'    => 8218,
+               'Scaron'   => 352,
+               'scaron'   => 353,
+               'sdot'     => 8901,
+               'sect'     => 167,
+               'shy'      => 173,
+               'Sigma'    => 931,
+               'sigma'    => 963,
+               'sigmaf'   => 962,
+               'sim'      => 8764,
+               'spades'   => 9824,
+               'sub'      => 8834,
+               'sube'     => 8838,
+               'sum'      => 8721,
+               'sup'      => 8835,
+               'sup1'     => 185,
+               'sup2'     => 178,
+               'sup3'     => 179,
+               'supe'     => 8839,
+               'szlig'    => 223,
+               'Tau'      => 932,
+               'tau'      => 964,
+               'there4'   => 8756,
+               'Theta'    => 920,
+               'theta'    => 952,
+               'thetasym' => 977,
+               'thinsp'   => 8201,
+               'THORN'    => 222,
+               'thorn'    => 254,
+               'tilde'    => 732,
+               'times'    => 215,
+               'trade'    => 8482,
+               'Uacute'   => 218,
+               'uacute'   => 250,
+               'uarr'     => 8593,
+               'uArr'     => 8657,
+               'Ucirc'    => 219,
+               'ucirc'    => 251,
+               'Ugrave'   => 217,
+               'ugrave'   => 249,
+               'uml'      => 168,
+               'upsih'    => 978,
+               'Upsilon'  => 933,
+               'upsilon'  => 965,
+               'Uuml'     => 220,
+               'uuml'     => 252,
+               'weierp'   => 8472,
+               'Xi'       => 926,
+               'xi'       => 958,
+               'Yacute'   => 221,
+               'yacute'   => 253,
+               'yen'      => 165,
+               'Yuml'     => 376,
+               'yuml'     => 255,
+               'Zeta'     => 918,
+               'zeta'     => 950,
+               'zwj'      => 8205,
+               'zwnj'     => 8204
+       );
+
+       /**
+        * Character entity aliases accepted by MediaWiki
+        */
+       static $htmlEntityAliases = array(
+               'רלמ' => 'rlm',
+               'رلم' => 'rlm',
+       );
+
+       /**
+        * Lazy-initialised attributes regex, see getAttribsRegex()
+        */
+       static $attribsRegex;
+
+       /**
+        * Regular expression to match HTML/XML attribute pairs within a tag.
+        * Allows some... latitude.
+        * Used in Sanitizer::fixTagAttributes and Sanitizer::decodeTagAttributes
+        */
+       static function getAttribsRegex() {
+               if ( self::$attribsRegex === null ) {
+                       $attribFirst = '[:A-Z_a-z0-9]';
+                       $attrib = '[:A-Z_a-z-.0-9]';
+                       $space = '[\x09\x0a\x0d\x20]';
+                       self::$attribsRegex = 
+                               "/(?:^|$space)({$attribFirst}{$attrib}*)
+                                 ($space*=$space*
+                                       (?:
+                                        # The attribute value: quoted or alone
+                                         \"([^<\"]*)\"
+                                        | '([^<']*)'
+                                        |  ([a-zA-Z0-9!#$%&()*,\\-.\\/:;<>?@[\\]^_`{|}~]+)
+                                        |  (\#[0-9a-fA-F]+) # Technically wrong, but lots of
+                                                                                # colors are specified like this.
+                                                                                # We'll be normalizing it.
+                                       )
+                               )?(?=$space|\$)/sx";
+               }
+               return self::$attribsRegex;
+       }
 
-class Sanitizer {
        /**
         * Cleans up HTML, removes dangerous tags and attributes, and
         * removes HTML comments
         * @private
-        * @param string $text
-        * @param callback $processCallback to do any variable or parameter replacements in HTML attribute values
-        * @param array $args for the processing callback
+        * @param $text String
+        * @param $processCallback Callback to do any variable or parameter replacements in HTML attribute values
+        * @param $args Array for the processing callback
+        * @param $extratags Array for any extra tags to include
+        * @param $removetags Array for any tags (default or extra) to exclude
         * @return string
         */
-       static function removeHTMLtags( $text, $processCallback = null, $args = array() ) {
-               global $wgUseTidy, $wgUserHtml;
+       static function removeHTMLtags( $text, $processCallback = null, $args = array(), $extratags = array(), $removetags = array() ) {
+               global $wgUseTidy;
 
-               static $htmlpairs, $htmlsingle, $htmlsingleonly, $htmlnest, $tabletags,
-                       $htmllist, $listtags, $htmlsingleallowed, $htmlelements, $staticInitialised;
+               static $htmlpairsStatic, $htmlsingle, $htmlsingleonly, $htmlnest, $tabletags,
+                       $htmllist, $listtags, $htmlsingleallowed, $htmlelementsStatic, $staticInitialised;
 
                wfProfileIn( __METHOD__ );
 
                if ( !$staticInitialised ) {
-                       if( $wgUserHtml ) {
-                               $htmlpairs = array( # Tags that must be closed
-                                       'b', 'del', 'i', 'ins', 'u', 'font', 'big', 'small', 'sub', 'sup', 'h1',
-                                       'h2', 'h3', 'h4', 'h5', 'h6', 'cite', 'code', 'em', 's',
-                                       'strike', 'strong', 'tt', 'var', 'div', 'center',
-                                       'blockquote', 'ol', 'ul', 'dl', 'table', 'caption', 'pre',
-                                       'ruby', 'rt' , 'rb' , 'rp', 'p', 'span', 'u'
-                               );
-                               $htmlsingle = array(
-                                       'br', 'hr', 'li', 'dt', 'dd'
-                               );
-                               $htmlsingleonly = array( # Elements that cannot have close tags
-                                       'br', 'hr'
-                               );
-                               $htmlnest = array( # Tags that can be nested--??
-                                       'table', 'tr', 'td', 'th', 'div', 'blockquote', 'ol', 'ul',
-                                       'dl', 'font', 'big', 'small', 'sub', 'sup', 'span'
-                               );
-                               $tabletags = array( # Can only appear inside table, we will close them
-                                       'td', 'th', 'tr',
-                               );
-                               $htmllist = array( # Tags used by list
-                                       'ul','ol',
-                               );
-                               $listtags = array( # Tags that can appear in a list
-                                       'li',
-                               );
 
-                       } else {
-                               $htmlpairs = array();
-                               $htmlsingle = array();
-                               $htmlnest = array();
-                               $tabletags = array();
+                       $htmlpairsStatic = array( # Tags that must be closed
+                               'b', 'del', 'i', 'ins', 'u', 'font', 'big', 'small', 'sub', 'sup', 'h1',
+                               'h2', 'h3', 'h4', 'h5', 'h6', 'cite', 'code', 'em', 's',
+                               'strike', 'strong', 'tt', 'var', 'div', 'center',
+                               'blockquote', 'ol', 'ul', 'dl', 'table', 'caption', 'pre',
+                               'ruby', 'rt' , 'rb' , 'rp', 'p', 'span', 'abbr', 'dfn',
+                               'kbd', 'samp'
+                       );
+                       $htmlsingle = array(
+                               'br', 'hr', 'li', 'dt', 'dd'
+                       );
+                       $htmlsingleonly = array( # Elements that cannot have close tags
+                               'br', 'hr'
+                       );
+                       $htmlnest = array( # Tags that can be nested--??
+                               'table', 'tr', 'td', 'th', 'div', 'blockquote', 'ol', 'ul',
+                               'dl', 'font', 'big', 'small', 'sub', 'sup', 'span'
+                       );
+                       $tabletags = array( # Can only appear inside table, we will close them
+                               'td', 'th', 'tr',
+                       );
+                       $htmllist = array( # Tags used by list
+                               'ul','ol',
+                       );
+                       $listtags = array( # Tags that can appear in a list
+                               'li',
+                       );
+
+                       global $wgAllowImageTag;
+                       if ( $wgAllowImageTag ) {
+                               $htmlsingle[] = 'img';
+                               $htmlsingleonly[] = 'img';
                        }
 
-                       $htmlsingleallowed = array_merge( $htmlsingle, $tabletags );
-                       $htmlelements = array_merge( $htmlsingle, $htmlpairs, $htmlnest );
+                       $htmlsingleallowed = array_unique( array_merge( $htmlsingle, $tabletags ) );
+                       $htmlelementsStatic = array_unique( array_merge( $htmlsingle, $htmlpairsStatic, $htmlnest ) );
 
                        # Convert them all to hashtables for faster lookup
-                       $vars = array( 'htmlpairs', 'htmlsingle', 'htmlsingleonly', 'htmlnest', 'tabletags', 
-                               'htmllist', 'listtags', 'htmlsingleallowed', 'htmlelements' );
+                       $vars = array( 'htmlpairsStatic', 'htmlsingle', 'htmlsingleonly', 'htmlnest', 'tabletags',
+                               'htmllist', 'listtags', 'htmlsingleallowed', 'htmlelementsStatic' );
                        foreach ( $vars as $var ) {
                                $$var = array_flip( $$var );
                        }
                        $staticInitialised = true;
                }
+               # Populate $htmlpairs and $htmlelements with the $extratags and $removetags arrays
+               $extratags = array_flip( $extratags );
+               $removetags = array_flip( $removetags );
+               $htmlpairs = array_merge( $extratags, $htmlpairsStatic );
+               $htmlelements = array_diff_key( array_merge( $extratags, $htmlelementsStatic ) , $removetags );
 
                # Remove HTML comments
                $text = Sanitizer::removeHTMLcomments( $text );
                $bits = explode( '<', $text );
                $text = str_replace( '>', '&gt;', array_shift( $bits ) );
-               if(!$wgUseTidy) {
+               if ( !$wgUseTidy ) {
                        $tagstack = $tablestack = array();
                        foreach ( $bits as $x ) {
                                $regs = array();
+                               # $slash: Does the current element start with a '/'?
+                               # $t: Current element name
+                               # $params: String between element name and >
+                               # $brace: Ending '>' or '/>'
+                               # $rest: Everything until the next element of $bits
                                if( preg_match( '!^(/?)(\\w+)([^>]*?)(/{0,1}>)([^<]*)$!', $x, $regs ) ) {
                                        list( /* $qbar */, $slash, $t, $params, $brace, $rest ) = $regs;
                                } else {
                                        $slash = $t = $params = $brace = $rest = null;
                                }
 
-                               $badtag = ;
+                               $badtag = false;
                                if ( isset( $htmlelements[$t = strtolower( $t )] ) ) {
                                        # Check our stack
-                                       if ( $slash ) {
-                                               # Closing a tag...
-                                               if( isset( $htmlsingleonly[$t] ) ) {
-                                                       $badtag = 1;
-                                               } elseif ( ( $ot = @array_pop( $tagstack ) ) != $t ) {
+                                       if ( $slash && isset( $htmlsingleonly[$t] ) ) {
+                                               $badtag = true;
+                                       } elseif ( $slash ) {
+                                               # Closing a tag... is it the one we just opened?
+                                               $ot = @array_pop( $tagstack );
+                                               if ( $ot != $t ) {
                                                        if ( isset( $htmlsingleallowed[$ot] ) ) {
                                                                # Pop all elements with an optional close tag
                                                                # and see if we find a match below them
                                                                $optstack = array();
-                                                               array_push ($optstack, $ot);
-                                                               while ( ( ( $ot = @array_pop( $tagstack ) ) != $t ) &&
-                                                                               isset( $htmlsingleallowed[$ot] ) ) 
-                                                               {
-                                                                       array_push ($optstack, $ot);
+                                                               array_push( $optstack, $ot );
+                                                               $ot = @array_pop( $tagstack );
+                                                               while ( $ot != $t && isset( $htmlsingleallowed[$ot] ) ) {
+                                                                       array_push( $optstack, $ot );
+                                                                       $ot = @array_pop( $tagstack );
                                                                }
                                                                if ( $t != $ot ) {
-                                                                       # No match. Push the optinal elements back again
-                                                                       $badtag = 1;
+                                                                       # No match. Push the optional elements back again
+                                                                       $badtag = true;
                                                                        while ( $ot = @array_pop( $optstack ) ) {
                                                                                array_push( $tagstack, $ot );
                                                                        }
@@ -423,8 +472,8 @@ class Sanitizer {
                                                        } else {
                                                                @array_push( $tagstack, $ot );
                                                                # <li> can be nested in <ul> or <ol>, skip those cases:
-                                                               if(!(isset( $htmllist[$ot] ) && isset( $listtags[$t] ) )) {
-                                                                       $badtag = 1;
+                                                               if ( !isset( $htmllist[$ot] ) || !isset( $listtags[$t] ) ) {
+                                                                       $badtag = true;
                                                                }
                                                        }
                                                } else {
@@ -436,23 +485,23 @@ class Sanitizer {
                                        } else {
                                                # Keep track for later
                                                if ( isset( $tabletags[$t] ) &&
-                                               ! in_array( 'table', $tagstack ) ) {
-                                                       $badtag = 1;
-                                               } else if ( in_array( $t, $tagstack ) &&
-                                               ! isset( $htmlnest [$t ] ) ) {
-                                                       $badtag = ;
+                                               !in_array( 'table', $tagstack ) ) {
+                                                       $badtag = true;
+                                               } elseif ( in_array( $t, $tagstack ) &&
+                                               !isset( $htmlnest [$t ] ) ) {
+                                                       $badtag = true;
                                                # Is it a self closed htmlpair ? (bug 5487)
-                                               } else if( $brace == '/>' &&
+                                               } elseif ( $brace == '/>' &&
                                                isset( $htmlpairs[$t] ) ) {
-                                                       $badtag = 1;
-                                               } elseif( isset( $htmlsingleonly[$t] ) ) {
+                                                       $badtag = true;
+                                               } elseif ( isset( $htmlsingleonly[$t] ) ) {
                                                        # Hack to force empty tag for uncloseable elements
                                                        $brace = '/>';
-                                               } else if( isset( $htmlsingle[$t] ) ) {
+                                               } elseif ( isset( $htmlsingle[$t] ) ) {
                                                        # Hack to not close $htmlsingle tags
-                                                       $brace = NULL;
-                                               } else if( isset( $tabletags[$t] )
-                                               &&  in_array($t ,$tagstack) ) {
+                                                       $brace = null;
+                                               } elseif ( isset( $tabletags[$t] )
+                                               && in_array( $t, $tagstack ) ) {
                                                        // New table tag but forgot to close the previous one
                                                        $text .= "</$t>";
                                                } else {
@@ -472,7 +521,7 @@ class Sanitizer {
                                                # Strip non-approved attributes from the tag
                                                $newparams = Sanitizer::fixTagAttributes( $params, $t );
                                        }
-                                       if ( ! $badtag ) {
+                                       if ( !$badtag ) {
                                                $rest = str_replace( '>', '&gt;', $rest );
                                                $close = ( $brace == '/>' && !$slash ) ? ' /' : '';
                                                $text .= "<$slash$t$newparams$close>$rest";
@@ -515,7 +564,7 @@ class Sanitizer {
         * trailing spaces and one of the newlines.
         *
         * @private
-        * @param string $text
+        * @param $text String
         * @return string
         */
        static function removeHTMLcomments( $text ) {
@@ -553,77 +602,312 @@ class Sanitizer {
                return $text;
        }
 
+       /**
+        * Take an array of attribute names and values and fix some deprecated values
+        * for the given element type.
+        * This does not validate properties, so you should ensure that you call
+        * validateTagAttributes AFTER this to ensure that the resulting style rule
+        * this may add is safe.
+        * 
+        * - Converts most presentational attributes like align into inline css
+        *
+        * @param $attribs Array
+        * @param $element String
+        * @return Array
+        */
+       static function fixDeprecatedAttributes( $attribs, $element ) {
+               global $wgHtml5, $wgCleanupPresentationalAttributes;
+               
+               // presentational attributes were removed from html5, we can leave them
+               // in when html5 is turned off
+               if ( !$wgHtml5 || !$wgCleanupPresentationalAttributes ) {
+                       return $attribs;
+               }
+               
+               $table = array( 'table' );
+               $cells = array( 'td', 'th' );
+               $colls = array( 'col', 'colgroup' );
+               $tblocks = array( 'tbody', 'tfoot', 'thead' );
+               $h = array( 'h1', 'h2', 'h3', 'h4', 'h5', 'h6' );
+               
+               $presentationalAttribs = array(
+                       'align' => array( 'text-align', array_merge( array( 'caption', 'hr', 'div', 'p', 'tr' ), $table, $cells, $colls, $tblocks, $h ) ),
+                       'clear' => array( 'clear', array( 'br' ) ),
+                       'height' => array( 'height', $cells ),
+                       'nowrap' => array( 'white-space', $cells ),
+                       'size' => array( 'height', array( 'hr' ) ),
+                       'type' => array( 'list-style-type', array( 'li', 'ol', 'ul' ) ),
+                       'valign' => array( 'vertical-align', array_merge( $cells, $colls, $tblocks ) ),
+                       'width' => array( 'width', array_merge( array( 'hr', 'pre' ), $table, $cells, $colls ) ),
+               );
+               
+               $style = "";
+               foreach ( $presentationalAttribs as $attribute => $info ) {
+                       list( $property, $elements ) = $info;
+                       
+                       // Skip if this attribute is not relevant to this element
+                       if ( !in_array( $element, $elements ) ) {
+                               continue;
+                       }
+                       
+                       // Skip if the attribute is not used
+                       if ( !array_key_exists( $attribute, $attribs ) ) {
+                               continue;
+                       }
+                       
+                       $value = $attribs[$attribute];
+                       
+                       // For nowrap the value should be nowrap instead of whatever text is in the value
+                       if ( $attribute === 'nowrap' ) {
+                               $value = 'nowrap';
+                       }
+                       
+                       // Size based properties should have px applied to them if they have no unit
+                       if ( in_array( $attribute, array( 'height', 'width', 'size' ) ) ) {
+                               if ( preg_match( '/^[\d.]+$/', $value ) ) {
+                                       $value = "{$value}px";
+                               }
+                       }
+                       
+                       $style .= " $property: $value;";
+                       
+                       unset( $attribs[$attribute] );
+               }
+               
+               if ( !empty($style) ) {
+                       // Prepend our style rules so that they can be overridden by user css
+                       if ( isset($attribs['style']) ) {
+                               $style .= " " . $attribs['style'];
+                       }
+                       $attribs['style'] = trim($style);
+               }
+               
+               return $attribs;
+       }
+
        /**
         * Take an array of attribute names and values and normalize or discard
         * illegal values for the given element type.
         *
         * - Discards attributes not on a whitelist for the given element
         * - Unsafe style attributes are discarded
+        * - Invalid id attributes are reencoded
         *
-        * @param array $attribs
-        * @param string $element
-        * @return array
+        * @param $attribs Array
+        * @param $element String
+        * @return Array
         *
         * @todo Check for legal values where the DTD limits things.
         * @todo Check for unique id attribute :P
         */
        static function validateTagAttributes( $attribs, $element ) {
-               $whitelist = array_flip( Sanitizer::attributeWhitelist( $element ) );
+               return Sanitizer::validateAttributes( $attribs,
+                       Sanitizer::attributeWhitelist( $element ) );
+       }
+
+       /**
+        * Take an array of attribute names and values and normalize or discard
+        * illegal values for the given whitelist.
+        *
+        * - Discards attributes not the given whitelist
+        * - Unsafe style attributes are discarded
+        * - Invalid id attributes are reencoded
+        *
+        * @param $attribs Array
+        * @param $whitelist Array: list of allowed attribute names
+        * @return Array
+        *
+        * @todo Check for legal values where the DTD limits things.
+        * @todo Check for unique id attribute :P
+        */
+       static function validateAttributes( $attribs, $whitelist ) {
+               global $wgAllowRdfaAttributes, $wgAllowMicrodataAttributes, $wgHtml5;
+
+               $whitelist = array_flip( $whitelist );
+               $hrefExp = '/^(' . wfUrlProtocols() . ')[^\s]+$/';
+
                $out = array();
                foreach( $attribs as $attribute => $value ) {
-                       if( !isset( $whitelist[$attribute] ) ) {
+                       #allow XML namespace declaration if RDFa is enabled
+                       if ( $wgAllowRdfaAttributes && preg_match( self::XMLNS_ATTRIBUTE_PATTERN, $attribute ) ) {
+                               if ( !preg_match( self::EVIL_URI_PATTERN, $value ) ) {
+                                       $out[$attribute] = $value;
+                               }
+
+                               continue;
+                       }
+
+                       # Allow any attribute beginning with "data-", if in HTML5 mode
+                       if ( !($wgHtml5 && preg_match( '/^data-/i', $attribute )) && !isset( $whitelist[$attribute] ) ) {
                                continue;
                        }
+
                        # Strip javascript "expression" from stylesheets.
                        # http://msdn.microsoft.com/workshop/author/dhtml/overview/recalc.asp
                        if( $attribute == 'style' ) {
                                $value = Sanitizer::checkCss( $value );
-                               if( $value === false ) {
-                                       # haxx0r
-                                       continue;
+                       }
+
+                       if ( $attribute === 'id' ) {
+                               $value = Sanitizer::escapeId( $value, 'noninitial' );
+                       }
+
+                       //RDFa and microdata properties allow URLs, URIs and/or CURIs. check them for sanity
+                       if ( $attribute === 'rel' || $attribute === 'rev' || 
+                               $attribute === 'about' || $attribute === 'property' || $attribute === 'resource' || #RDFa
+                               $attribute === 'datatype' || $attribute === 'typeof' ||                             #RDFa
+                               $attribute === 'itemid' || $attribute === 'itemprop' || $attribute === 'itemref' || #HTML5 microdata
+                               $attribute === 'itemscope' || $attribute === 'itemtype' ) {                         #HTML5 microdata
+
+                               //Paranoia. Allow "simple" values but suppress javascript
+                               if ( preg_match( self::EVIL_URI_PATTERN, $value ) ) {
+                                       continue; 
                                }
                        }
 
-                       if ( $attribute === 'id' )
-                               $value = Sanitizer::escapeId( $value );
+                       # NOTE: even though elements using href/src are not allowed directly, supply
+                       #       validation code that can be used by tag hook handlers, etc
+                       if ( $attribute === 'href' || $attribute === 'src' ) {
+                               if ( !preg_match( $hrefExp, $value ) ) {
+                                       continue; //drop any href or src attributes not using an allowed protocol.
+                                                 //NOTE: this also drops all relative URLs
+                               }
+                       }
 
                        // If this attribute was previously set, override it.
                        // Output should only have one attribute of each name.
                        $out[$attribute] = $value;
                }
+
+               if ( $wgAllowMicrodataAttributes ) {
+                       # itemtype, itemid, itemref don't make sense without itemscope
+                       if ( !array_key_exists( 'itemscope', $out ) ) {
+                               unset( $out['itemtype'] );
+                               unset( $out['itemid'] );
+                               unset( $out['itemref'] );
+                       }
+                       # TODO: Strip itemprop if we aren't descendants of an itemscope.
+               }
+               return $out;
+       }
+
+       /**
+        * Merge two sets of HTML attributes.  Conflicting items in the second set
+        * will override those in the first, except for 'class' attributes which
+        * will be combined (if they're both strings).
+        *
+        * @todo implement merging for other attributes such as style
+        * @param $a Array
+        * @param $b Array
+        * @return array
+        */
+       static function mergeAttributes( $a, $b ) {
+               $out = array_merge( $a, $b );
+               if( isset( $a['class'] ) && isset( $b['class'] )
+               && is_string( $a['class'] ) && is_string( $b['class'] )
+               && $a['class'] !== $b['class'] ) {
+                       $classes = preg_split( '/\s+/', "{$a['class']} {$b['class']}",
+                               -1, PREG_SPLIT_NO_EMPTY );
+                       $out['class'] = implode( ' ', array_unique( $classes ) );
+               }
                return $out;
        }
-       
+
        /**
         * Pick apart some CSS and check it for forbidden or unsafe structures.
-        * Returns a sanitized string, or false if it was just too evil.
+        * Returns a sanitized string. This sanitized string will have
+        * character references and escape sequences decoded, and comments
+        * stripped. If the input is just too evil, only a comment complaining
+        * about evilness will be returned.
         *
         * Currently URL references, 'expression', 'tps' are forbidden.
         *
-        * @param string $value
-        * @return mixed
+        * NOTE: Despite the fact that character references are decoded, the
+        * returned string may contain character references given certain
+        * clever input strings. These character references must
+        * be escaped before the return value is embedded in HTML.
+        * 
+        * @param $value String
+        * @return String
         */
        static function checkCss( $value ) {
-               $stripped = Sanitizer::decodeCharReferences( $value );
-
-               // Remove any comments; IE gets token splitting wrong
-               $stripped = StringUtils::delimiterReplace( '/*', '*/', ' ', $stripped );
-               
-               $value = $stripped;
-
-               // ... and continue checks
-               $stripped = preg_replace( '!\\\\([0-9A-Fa-f]{1,6})[ \\n\\r\\t\\f]?!e',
-                       'codepointToUtf8(hexdec("$1"))', $stripped );
-               $stripped = str_replace( '\\', '', $stripped );
-               if( preg_match( '/(expression|tps*:\/\/|url\\s*\().*/is',
-                               $stripped ) ) {
-                       # haxx0r
-                       return false;
+               // Decode character references like &#123;
+               $value = Sanitizer::decodeCharReferences( $value );
+
+               // Decode escape sequences and line continuation
+               // See the grammar in the CSS 2 spec, appendix D.
+               // This has to be done AFTER decoding character references.
+               // This means it isn't possible for this function to return
+               // unsanitized escape sequences. It is possible to manufacture
+               // input that contains character references that decode to
+               // escape sequences that decode to character references, but
+               // it's OK for the return value to contain character references
+               // because the caller is supposed to escape those anyway.
+               static $decodeRegex;
+               if ( !$decodeRegex ) {
+                       $space = '[\\x20\\t\\r\\n\\f]';
+                       $nl = '(?:\\n|\\r\\n|\\r|\\f)';
+                       $backslash = '\\\\';
+                       $decodeRegex = "/ $backslash 
+                               (?:
+                                       ($nl) |  # 1. Line continuation
+                                       ([0-9A-Fa-f]{1,6})$space? |  # 2. character number
+                                       (.) | # 3. backslash cancelling special meaning
+                                       () | # 4. backslash at end of string
+                               )/xu";
                }
+               $value = preg_replace_callback( $decodeRegex,
+                       array( __CLASS__, 'cssDecodeCallback' ), $value );
                
+               // Remove any comments; IE gets token splitting wrong
+               // This must be done AFTER decoding character references and
+               // escape sequences, because those steps can introduce comments
+               // This step cannot introduce character references or escape
+               // sequences, because it replaces comments with spaces rather
+               // than removing them completely.
+               $value = StringUtils::delimiterReplace( '/*', '*/', ' ', $value );
+
+               // Remove anything after a comment-start token, to guard against
+               // incorrect client implementations.
+               $commentPos = strpos( $value, '/*' );
+               if ( $commentPos !== false ) {
+                       $value = substr( $value, 0, $commentPos );
+               }
+
+               // Reject problematic keywords and control characters
+               if ( preg_match( '/[\000-\010\016-\037\177]/', $value ) ) {
+                       return '/* invalid control char */';
+               } elseif ( preg_match( '! expression | filter\s*: | accelerator\s*: | url\s*\( !ix', $value ) ) {
+                       return '/* insecure input */';
+               }
                return $value;
        }
 
+       /**
+        * @param $matches array
+        * @return String
+        */
+       static function cssDecodeCallback( $matches ) {
+               if ( $matches[1] !== '' ) {
+                       // Line continuation
+                       return '';
+               } elseif ( $matches[2] !== '' ) {
+                       $char = codepointToUtf8( hexdec( $matches[2] ) );
+               } elseif ( $matches[3] !== '' ) {
+                       $char = $matches[3];
+               } else {
+                       $char = '\\';
+               }
+               if ( $char == "\n" || $char == '"' || $char == "'" || $char == '\\' ) {
+                       // These characters need to be escaped in strings
+                       // Clean up the escape sequence to avoid parsing errors by clients
+                       return '\\' . dechex( ord( $char ) ) . ' ';
+               } else {
+                       // Decode unnecessary escape
+                       return $char;
+               }
+       }
+
        /**
         * Take a tag soup fragment listing an HTML element's attributes
         * and normalize it to well-formed XML, discarding unwanted attributes.
@@ -639,17 +923,18 @@ class Sanitizer {
         * - Unsafe style attributes are discarded
         * - Prepends space if there are attributes.
         *
-        * @param string $text
-        * @param string $element
-        * @return string
+        * @param $text String
+        * @param $element String
+        * @return String
         */
        static function fixTagAttributes( $text, $element ) {
                if( trim( $text ) == '' ) {
                        return '';
                }
 
-               $stripped = Sanitizer::validateTagAttributes(
-                       Sanitizer::decodeTagAttributes( $text ), $element );
+               $decoded = Sanitizer::decodeTagAttributes( $text );
+               $decoded = Sanitizer::fixDeprecatedAttributes( $decoded, $element );
+               $stripped = Sanitizer::validateTagAttributes( $decoded, $element );
 
                $attribs = array();
                foreach( $stripped as $attribute => $value ) {
@@ -663,11 +948,11 @@ class Sanitizer {
 
        /**
         * Encode an attribute value for HTML output.
-        * @param $text
+        * @param $text String
         * @return HTML-encoded text fragment
         */
        static function encodeAttribute( $text ) {
-               $encValue = htmlspecialchars( $text );
+               $encValue = htmlspecialchars( $text, ENT_QUOTES );
 
                // Whitespace is normalized during attribute decoding,
                // so if we've been passed non-spaces we must encode them
@@ -684,7 +969,7 @@ class Sanitizer {
        /**
         * Encode an attribute value for HTML tags, with extra armoring
         * against further wiki processing.
-        * @param $text
+        * @param $text String
         * @return HTML-encoded text fragment
         */
        static function safeEncodeAttribute( $text ) {
@@ -715,28 +1000,67 @@ class Sanitizer {
        }
 
        /**
-        * Given a value escape it so that it can be used in an id attribute and
-        * return it, this does not validate the value however (see first link)
+        * Given a value, escape it so that it can be used in an id attribute and
+        * return it.  This will use HTML5 validation if $wgExperimentalHtmlIds is
+        * true, allowing anything but ASCII whitespace.  Otherwise it will use
+        * HTML 4 rules, which means a narrow subset of ASCII, with bad characters
+        * escaped with lots of dots.
         *
-        * @link http://www.w3.org/TR/html401/types.html#type-name Valid characters
+        * To ensure we don't have to bother escaping anything, we also strip ', ",
+        * & even if $wgExperimentalIds is true.  TODO: Is this the best tactic?
+        * We also strip # because it upsets IE, and % because it could be
+        * ambiguous if it's part of something that looks like a percent escape
+        * (which don't work reliably in fragments cross-browser).
+        *
+        * @see http://www.w3.org/TR/html401/types.html#type-name Valid characters
         *                                                          in the id and
         *                                                          name attributes
-        * @link http://www.w3.org/TR/html401/struct/links.html#h-12.2.3 Anchors with the id attribute
-        *
-        * @static
+        * @see http://www.w3.org/TR/html401/struct/links.html#h-12.2.3 Anchors with the id attribute
+        * @see http://www.whatwg.org/specs/web-apps/current-work/multipage/elements.html#the-id-attribute
+        *   HTML5 definition of id attribute
         *
-        * @param string $id
-        * @return string
+        * @param $id String: id to escape
+        * @param $options Mixed: string or array of strings (default is array()):
+        *   'noninitial': This is a non-initial fragment of an id, not a full id,
+        *       so don't pay attention if the first character isn't valid at the
+        *       beginning of an id.  Only matters if $wgExperimentalHtmlIds is
+        *       false.
+        *   'legacy': Behave the way the old HTML 4-based ID escaping worked even
+        *       if $wgExperimentalHtmlIds is used, so we can generate extra
+        *       anchors and links won't break.
+        * @return String
         */
-       static function escapeId( $id ) {
+       static function escapeId( $id, $options = array() ) {
+               global $wgHtml5, $wgExperimentalHtmlIds;
+               $options = (array)$options;
+
+               if ( $wgHtml5 && $wgExperimentalHtmlIds && !in_array( 'legacy', $options ) ) {
+                       $id = Sanitizer::decodeCharReferences( $id );
+                       $id = preg_replace( '/[ \t\n\r\f_\'"&#%]+/', '_', $id );
+                       $id = trim( $id, '_' );
+                       if ( $id === '' ) {
+                               # Must have been all whitespace to start with.
+                               return '_';
+                       } else {
+                               return $id;
+                       }
+               }
+
+               # HTML4-style escaping
                static $replace = array(
                        '%3A' => ':',
                        '%' => '.'
                );
 
                $id = urlencode( Sanitizer::decodeCharReferences( strtr( $id, ' ', '_' ) ) );
+               $id = str_replace( array_keys( $replace ), array_values( $replace ), $id );
 
-               return str_replace( array_keys( $replace ), array_values( $replace ), $id );
+               if ( !preg_match( '/^[a-zA-Z]/', $id )
+               && !in_array( 'noninitial', $options ) )  {
+                       // Initial character must be a letter!
+                       $id = "x$id";
+               }
+               return $id;
        }
 
        /**
@@ -745,10 +1069,10 @@ class Sanitizer {
         *
         * @todo For extra validity, input should be validated UTF-8.
         *
-        * @link http://www.w3.org/TR/CSS21/syndata.html Valid characters/format
+        * @see http://www.w3.org/TR/CSS21/syndata.html Valid characters/format
         *
-        * @param string $class
-        * @return string
+        * @param $class String
+        * @return String
         */
        static function escapeClass( $class ) {
                // Convert ugly stuff to underscores and kill underscores in ugly places
@@ -758,11 +1082,25 @@ class Sanitizer {
                        $class ), '_');
        }
 
+       /**
+        * Given HTML input, escape with htmlspecialchars but un-escape entites.
+        * This allows (generally harmless) entities like &#160; to survive.
+        *
+        * @param $html String to escape
+        * @return String: escaped input
+        */
+       static function escapeHtmlAllowEntities( $html ) {
+               $html = Sanitizer::decodeCharReferences( $html );
+               # It seems wise to escape ' as well as ", as a matter of course.  Can't
+               # hurt.
+               $html = htmlspecialchars( $html, ENT_QUOTES );
+               return $html;
+       }
+
        /**
         * Regex replace callback for armoring links against further processing.
-        * @param array $matches
+        * @param $matches Array
         * @return string
-        * @private
         */
        private static function armorLinksCallback( $matches ) {
                return str_replace( ':', '&#58;', $matches[1] );
@@ -773,19 +1111,18 @@ class Sanitizer {
         * a partial tag string. Attribute names are forces to lowercase,
         * character references are decoded to UTF-8 text.
         *
-        * @param string
-        * @return array
+        * @param $text String
+        * @return Array
         */
-       static function decodeTagAttributes( $text ) {
-               $attribs = array();
-
+       public static function decodeTagAttributes( $text ) {
                if( trim( $text ) == '' ) {
-                       return $attribs;
+                       return array();
                }
 
+               $attribs = array();
                $pairs = array();
                if( !preg_match_all(
-                       MW_ATTRIBS_REGEX,
+                       self::getAttribsRegex(),
                        $text,
                        $pairs,
                        PREG_SET_ORDER ) ) {
@@ -808,11 +1145,10 @@ class Sanitizer {
 
        /**
         * Pick the appropriate attribute value from a match set from the
-        * MW_ATTRIBS_REGEX matches.
+        * attribs regex matches.
         *
-        * @param array $set
-        * @return string
-        * @private
+        * @param $set Array
+        * @return String
         */
        private static function getTagAttributeCallback( $set ) {
                if( isset( $set[6] ) ) {
@@ -844,41 +1180,62 @@ class Sanitizer {
         * but note that we're not returning the value, but are returning
         * XML source fragments that will be slapped into output.
         *
-        * @param string $text
-        * @return string
-        * @private
+        * @param $text String
+        * @return String
         */
        private static function normalizeAttributeValue( $text ) {
                return str_replace( '"', '&quot;',
-                       preg_replace(
-                               '/\r\n|[\x20\x0d\x0a\x09]/',
-                               ' ',
+                       self::normalizeWhitespace(
                                Sanitizer::normalizeCharReferences( $text ) ) );
        }
 
+       /**
+        * @param $text string
+        * @return mixed
+        */
+       private static function normalizeWhitespace( $text ) {
+               return preg_replace(
+                       '/\r\n|[\x20\x0d\x0a\x09]/',
+                       ' ',
+                       $text );
+       }
+
+       /**
+        * Normalizes whitespace in a section name, such as might be returned
+        * by Parser::stripSectionName(), for use in the id's that are used for
+        * section links.
+        *
+        * @param $section String
+        * @return String
+        */
+       static function normalizeSectionNameWhitespace( $section ) {
+               return trim( preg_replace( '/[ _]+/', ' ', $section ) );
+       }
+
        /**
         * Ensure that any entities and character references are legal
         * for XML and XHTML specifically. Any stray bits will be
         * &amp;-escaped to result in a valid text fragment.
         *
-        * a. any named char refs must be known in XHTML
+        * a. named char refs can only be &lt; &gt; &amp; &quot;, others are
+        *   numericized (this way we're well-formed even without a DTD)
         * b. any numeric char refs must be legal chars, not invalid or forbidden
         * c. use &#x, not &#X
         * d. fix or reject non-valid attributes
         *
-        * @param string $text
-        * @return string
+        * @param $text String
+        * @return String
         * @private
         */
        static function normalizeCharReferences( $text ) {
                return preg_replace_callback(
-                       MW_CHAR_REFS_REGEX,
+                       self::CHAR_REFS_REGEX,
                        array( 'Sanitizer', 'normalizeCharReferencesCallback' ),
                        $text );
        }
        /**
-        * @param string $matches
-        * @return string
+        * @param $matches String
+        * @return String
         */
        static function normalizeCharReferencesCallback( $matches ) {
                $ret = null;
@@ -888,8 +1245,6 @@ class Sanitizer {
                        $ret = Sanitizer::decCharReference( $matches[2] );
                } elseif( $matches[3] != ''  ) {
                        $ret = Sanitizer::hexCharReference( $matches[3] );
-               } elseif( $matches[4] != '' ) {
-                       $ret = Sanitizer::hexCharReference( $matches[4] );
                }
                if( is_null( $ret ) ) {
                        return htmlspecialchars( $matches[0] );
@@ -900,22 +1255,31 @@ class Sanitizer {
 
        /**
         * If the named entity is defined in the HTML 4.0/XHTML 1.0 DTD,
-        * return the named entity reference as is. Otherwise, returns
-        * HTML-escaped text of pseudo-entity source (eg &amp;foo;)
+        * return the equivalent numeric entity reference (except for the core &lt;
+        * &gt; &amp; &quot;). If the entity is a MediaWiki-specific alias, returns
+        * the HTML equivalent. Otherwise, returns HTML-escaped text of
+        * pseudo-entity source (eg &amp;foo;)
         *
-        * @param string $name
-        * @return string
-        * @static
+        * @param $name String
+        * @return String
         */
        static function normalizeEntity( $name ) {
-               global $wgHtmlEntities;
-               if( isset( $wgHtmlEntities[$name] ) ) {
+               if ( isset( self::$htmlEntityAliases[$name] ) ) {
+                       return '&' . self::$htmlEntityAliases[$name] . ';';
+               } elseif ( in_array( $name,
+               array( 'lt', 'gt', 'amp', 'quot' ) ) ) {
                        return "&$name;";
+               } elseif ( isset( self::$htmlEntities[$name] ) ) {
+                       return '&#' . self::$htmlEntities[$name] . ';';
                } else {
                        return "&amp;$name;";
                }
        }
 
+       /**
+        * @param $codepoint
+        * @return null|string
+        */
        static function decCharReference( $codepoint ) {
                $point = intval( $codepoint );
                if( Sanitizer::validateCodepoint( $point ) ) {
@@ -925,6 +1289,10 @@ class Sanitizer {
                }
        }
 
+       /**
+        * @param $codepoint
+        * @return null|string
+        */
        static function hexCharReference( $codepoint ) {
                $point = hexdec( $codepoint );
                if( Sanitizer::validateCodepoint( $point ) ) {
@@ -936,8 +1304,8 @@ class Sanitizer {
 
        /**
         * Returns true if a given Unicode codepoint is a valid character in XML.
-        * @param int $codepoint
-        * @return bool
+        * @param $codepoint Integer
+        * @return Boolean
         */
        private static function validateCodepoint( $codepoint ) {
                return ($codepoint ==    0x09)
@@ -952,21 +1320,43 @@ class Sanitizer {
         * Decode any character references, numeric or named entities,
         * in the text and return a UTF-8 string.
         *
-        * @param string $text
-        * @return string
-        * @public
-        * @static
+        * @param $text String
+        * @return String
         */
        public static function decodeCharReferences( $text ) {
                return preg_replace_callback(
-                       MW_CHAR_REFS_REGEX,
+                       self::CHAR_REFS_REGEX,
                        array( 'Sanitizer', 'decodeCharReferencesCallback' ),
                        $text );
        }
 
        /**
-        * @param string $matches
-        * @return string
+        * Decode any character references, numeric or named entities,
+        * in the next and normalize the resulting string. (bug 14952)
+        *
+        * This is useful for page titles, not for text to be displayed,
+        * MediaWiki allows HTML entities to escape normalization as a feature.
+        *
+        * @param $text String (already normalized, containing entities)
+        * @return String (still normalized, without entities)
+        */
+       public static function decodeCharReferencesAndNormalize( $text ) {
+               global $wgContLang;
+               $text = preg_replace_callback(
+                       self::CHAR_REFS_REGEX,
+                       array( 'Sanitizer', 'decodeCharReferencesCallback' ),
+                       $text, /* limit */ -1, $count );
+
+               if ( $count ) {
+                       return $wgContLang->normalize( $text );
+               } else {
+                       return $text;
+               }
+       }
+
+       /**
+        * @param $matches String
+        * @return String
         */
        static function decodeCharReferencesCallback( $matches ) {
                if( $matches[1] != '' ) {
@@ -975,8 +1365,6 @@ class Sanitizer {
                        return  Sanitizer::decodeChar( intval( $matches[2] ) );
                } elseif( $matches[3] != ''  ) {
                        return  Sanitizer::decodeChar( hexdec( $matches[3] ) );
-               } elseif( $matches[4] != '' ) {
-                       return  Sanitizer::decodeChar( hexdec( $matches[4] ) );
                }
                # Last case should be an ampersand by itself
                return $matches[0];
@@ -985,8 +1373,8 @@ class Sanitizer {
        /**
         * Return UTF-8 string for a codepoint if that is a valid
         * character reference, otherwise U+FFFD REPLACEMENT CHARACTER.
-        * @param int $codepoint
-        * @return string
+        * @param $codepoint Integer
+        * @return String
         * @private
         */
        static function decodeChar( $codepoint ) {
@@ -1002,24 +1390,25 @@ class Sanitizer {
         * return the UTF-8 encoding of that character. Otherwise, returns
         * pseudo-entity source (eg &foo;)
         *
-        * @param string $name
-        * @return string
+        * @param $name String
+        * @return String
         */
        static function decodeEntity( $name ) {
-               global $wgHtmlEntities;
-               if( isset( $wgHtmlEntities[$name] ) ) {
-                       return codepointToUtf8( $wgHtmlEntities[$name] );
+               if ( isset( self::$htmlEntityAliases[$name] ) ) {
+                       $name = self::$htmlEntityAliases[$name];
+               }
+               if( isset( self::$htmlEntities[$name] ) ) {
+                       return codepointToUtf8( self::$htmlEntities[$name] );
                } else {
                        return "&$name;";
                }
        }
 
        /**
-        * Fetch the whitelist of acceptable attributes for a given
-        * element name.
+        * Fetch the whitelist of acceptable attributes for a given element name.
         *
-        * @param string $element
-        * @return array
+        * @param $element String
+        * @return Array
         */
        static function attributeWhitelist( $element ) {
                static $list;
@@ -1032,11 +1421,29 @@ class Sanitizer {
        }
 
        /**
-        * @todo Document it a bit
-        * @return array
+        * Foreach array key (an allowed HTML element), return an array
+        * of allowed attributes
+        * @return Array
         */
        static function setupAttributeWhitelist() {
+               global $wgAllowRdfaAttributes, $wgHtml5, $wgAllowMicrodataAttributes;
+
                $common = array( 'id', 'class', 'lang', 'dir', 'title', 'style' );
+
+               if ( $wgAllowRdfaAttributes ) {
+                       #RDFa attributes as specified in section 9 of http://www.w3.org/TR/2008/REC-rdfa-syntax-20081014
+                       $common = array_merge( $common, array(
+                           'about', 'property', 'resource', 'datatype', 'typeof', 
+                       ) );
+               }
+
+               if ( $wgHtml5 && $wgAllowMicrodataAttributes ) {
+                       # add HTML5 microdata tages as pecified by http://www.whatwg.org/specs/web-apps/current-work/multipage/microdata.html#the-microdata-model
+                       $common = array_merge( $common, array(
+                           'itemid', 'itemprop', 'itemref', 'itemscope', 'itemtype'
+                       ) );
+               }
+
                $block = array_merge( $common, array( 'align' ) );
                $tablealign = array( 'align', 'char', 'charoff', 'valign' );
                $tablecell = array( 'abbr',
@@ -1077,12 +1484,12 @@ class Sanitizer {
                        'em'         => $common,
                        'strong'     => $common,
                        'cite'       => $common,
-                       # dfn
+                       'dfn'        => $common,
                        'code'       => $common,
-                       # samp
-                       # kbd
+                       'samp'       => $common,
+                       'kbd'        => $common,
                        'var'        => $common,
-                       # abbr
+                       'abbr'       => $common,
                        # acronym
 
                        # 9.2.2
@@ -1142,6 +1549,15 @@ class Sanitizer {
                        'td'         => array_merge( $common, $tablecell, $tablealign ),
                        'th'         => array_merge( $common, $tablecell, $tablealign ),
 
+                       # 12.2 # NOTE: <a> is not allowed directly, but the attrib whitelist is used from the Parser object
+                       'a'          => array_merge( $common, array( 'href', 'rel', 'rev' ) ), # rel/rev esp. for RDFa 
+
+                       # 13.2
+                       # Not usually allowed, but may be used for extension-style hooks
+                       # such as <math> when it is rasterized, or if $wgAllowImageTag is
+                       # true
+                       'img'        => array_merge( $common, array( 'alt', 'src', 'width', 'height' ) ),
+
                        # 15.2.1
                        'tt'         => $common,
                        'b'          => $common,
@@ -1167,31 +1583,32 @@ class Sanitizer {
                        'rb'         => $common,
                        'rt'         => $common, #array_merge( $common, array( 'rbspan' ) ),
                        'rp'         => $common,
+
+                       # MathML root element, where used for extensions
+                       # 'title' may not be 100% valid here; it's XHTML
+                       # http://www.w3.org/TR/REC-MathML/
+                       'math'       => array( 'class', 'style', 'id', 'title' ),
                        );
                return $whitelist;
        }
 
        /**
         * Take a fragment of (potentially invalid) HTML and return
-        * a version with any tags removed, encoded suitably for literal
-        * inclusion in an attribute value.
+        * a version with any tags removed, encoded as plain text.
         *
-        * @param string $text HTML fragment
-        * @return string
+        * Warning: this return value must be further escaped for literal
+        * inclusion in HTML output as of 1.10!
+        *
+        * @param $text String: HTML fragment
+        * @return String
         */
        static function stripAllTags( $text ) {
                # Actual <tags>
                $text = StringUtils::delimiterReplace( '<', '>', '', $text );
 
                # Normalize &entities and whitespace
-               $text = Sanitizer::normalizeAttributeValue( $text );
-
-               # Will be placed into "double-quoted" attributes,
-               # make sure remaining bits are safe.
-               $text = str_replace(
-                       array('<', '>', '"'),
-                       array('&lt;', '&gt;', '&quot;'),
-                       $text );
+               $text = self::decodeCharReferences( $text );
+               $text = self::normalizeWhitespace( $text );
 
                return $text;
        }
@@ -1203,26 +1620,29 @@ class Sanitizer {
         *
         * Use for passing XHTML fragments to PHP's XML parsing functions
         *
-        * @return string
-        * @static
+        * @return String
         */
        static function hackDocType() {
-               global $wgHtmlEntities;
                $out = "<!DOCTYPE html [\n";
-               foreach( $wgHtmlEntities as $entity => $codepoint ) {
+               foreach( self::$htmlEntities as $entity => $codepoint ) {
                        $out .= "<!ENTITY $entity \"&#$codepoint;\">";
                }
                $out .= "]>\n";
                return $out;
        }
 
-       static function cleanUrl( $url, $hostname=true ) {
+       /**
+        * @param $url string
+        * @return mixed|string
+        */
+       static function cleanUrl( $url ) {
                # Normalize any HTML entities in input. They will be
                # re-escaped by makeExternalLink().
                $url = Sanitizer::decodeCharReferences( $url );
 
                # Escape any control characters introduced by the above step
-               $url = preg_replace( '/[\][<>"\\x00-\\x20\\x7F]/e', "urlencode('\\0')", $url );
+               $url = preg_replace_callback( '/[\][<>"\\x00-\\x20\\x7F\|]/', 
+                       array( __CLASS__, 'cleanUrlCallback' ), $url );
 
                # Validate hostname portion
                $matches = array();
@@ -1250,7 +1670,7 @@ class Sanitizer {
 
                        $host = preg_replace( $strip, '', $host );
 
-                       // @fixme: validate hostnames here
+                       // @todo FIXME: Validate hostnames here
 
                        return $protocol . $host . $rest;
                } else {
@@ -1258,6 +1678,63 @@ class Sanitizer {
                }
        }
 
-}
+       /**
+        * @param $matches array
+        * @return string
+        */
+       static function cleanUrlCallback( $matches ) {
+               return urlencode( $matches[0] );
+       }
 
-?>
+       /**
+        * Does a string look like an e-mail address?
+        *
+        * This validates an email address using an HTML5 specification found at:
+        * http://www.whatwg.org/specs/web-apps/current-work/multipage/states-of-the-type-attribute.html#valid-e-mail-address
+        * Which as of 2011-01-24 says:
+        *
+        *   A valid e-mail address is a string that matches the ABNF production
+        *   1*( atext / "." ) "@" ldh-str *( "." ldh-str ) where atext is defined
+        *   in RFC 5322 section 3.2.3, and ldh-str is defined in RFC 1034 section
+        *   3.5.
+        *
+        * This function is an implementation of the specification as requested in
+        * bug 22449.
+        *
+        * Client-side forms will use the same standard validation rules via JS or
+        * HTML 5 validation; additional restrictions can be enforced server-side
+        * by extensions via the 'isValidEmailAddr' hook.
+        *
+        * Note that this validation doesn't 100% match RFC 2822, but is believed
+        * to be liberal enough for wide use. Some invalid addresses will still
+        * pass validation here.
+        *
+        * @since 1.18
+        *
+        * @param $addr String E-mail address
+        * @return Bool
+        */
+       public static function validateEmail( $addr ) {
+               $result = null;
+               if( !wfRunHooks( 'isValidEmailAddr', array( $addr, &$result ) ) ) {
+                       return $result;
+               }
+
+               // Please note strings below are enclosed in brackets [], this make the
+               // hyphen "-" a range indicator. Hence it is double backslashed below.
+               // See bug 26948
+               $rfc5322_atext   = "a-z0-9!#$%&'*+\\-\/=?^_`{|}~" ;
+               $rfc1034_ldh_str = "a-z0-9\\-" ;
+
+               $HTML5_email_regexp = "/
+               ^                      # start of string
+               [$rfc5322_atext\\.]+    # user part which is liberal :p
+               @                      # 'apostrophe'
+               [$rfc1034_ldh_str]+       # First domain part
+               (\\.[$rfc1034_ldh_str]+)*  # Following part prefixed with a dot
+               $                      # End of string
+               /ix" ; // case Insensitive, eXtended
+
+               return (bool) preg_match( $HTML5_email_regexp, $addr );
+       }
+}