| commit | author | age | ||
| 7ac944 | 1 | <?php |
| AM | 2 | |
| 3 | /** | |
| 4 | +-----------------------------------------------------------------------+ | |
| 5 | | This file is part of the Roundcube Webmail client | | |
| 6 | | Copyright (C) 2008-2012, The Roundcube Dev Team | | |
| 7 | | | | |
| 8 | | Licensed under the GNU General Public License version 3 or | | |
| 9 | | any later version with exceptions for skins & plugins. | | |
| 10 | | See the README file for a full license statement. | | |
| 11 | | | | |
| 12 | | PURPOSE: | | |
| 13 | | Utility class providing HTML sanityzer (based on Washtml class) | | |
| 14 | +-----------------------------------------------------------------------+ | |
| 15 | | Author: Thomas Bruederli <roundcube@gmail.com> | | |
| 16 | | Author: Aleksander Machniak <alec@alec.pl> | | |
| 17 | | Author: Frederic Motte <fmotte@ubixis.com> | | |
| 18 | +-----------------------------------------------------------------------+ | |
| 19 | */ | |
| 20 | ||
| 21 | /** | |
| 22 | * Washtml, a HTML sanityzer. | |
| 23 | * | |
| 24 | * Copyright (c) 2007 Frederic Motte <fmotte@ubixis.com> | |
| 25 | * All rights reserved. | |
| 26 | * | |
| 27 | * Redistribution and use in source and binary forms, with or without | |
| 28 | * modification, are permitted provided that the following conditions | |
| 29 | * are met: | |
| 30 | * 1. Redistributions of source code must retain the above copyright | |
| 31 | * notice, this list of conditions and the following disclaimer. | |
| 32 | * 2. Redistributions in binary form must reproduce the above copyright | |
| 33 | * notice, this list of conditions and the following disclaimer in the | |
| 34 | * documentation and/or other materials provided with the distribution. | |
| 35 | * | |
| 36 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR | |
| 37 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES | |
| 38 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. | |
| 39 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, | |
| 40 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT | |
| 41 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, | |
| 42 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY | |
| 43 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT | |
| 44 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF | |
| 45 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | |
| 46 | * | |
| 47 | * OVERVIEW: | |
| 48 | * | |
| 49 | * Wahstml take an untrusted HTML and return a safe html string. | |
| 50 | * | |
| 51 | * SYNOPSIS: | |
| 52 | * | |
| 53 | * $washer = new washtml($config); | |
| 54 | * $washer->wash($html); | |
| 55 | * It return a sanityzed string of the $html parameter without html and head tags. | |
| 56 | * $html is a string containing the html code to wash. | |
| 57 | * $config is an array containing options: | |
| 58 | * $config['allow_remote'] is a boolean to allow link to remote images. | |
| 59 | * $config['blocked_src'] string with image-src to be used for blocked remote images | |
| 60 | * $config['show_washed'] is a boolean to include washed out attributes as x-washed | |
| 61 | * $config['cid_map'] is an array where cid urls index urls to replace them. | |
| 62 | * $config['charset'] is a string containing the charset of the HTML document if it is not defined in it. | |
| 63 | * $washer->extlinks is a reference to a boolean that is set to true if remote images were removed. (FE: show remote images link) | |
| 64 | * | |
| 65 | * INTERNALS: | |
| 66 | * | |
| 67 | * Only tags and attributes in the static lists $html_elements and $html_attributes | |
| 68 | * are kept, inline styles are also filtered: all style identifiers matching | |
| 69 | * /[a-z\-]/i are allowed. Values matching colors, sizes, /[a-z\-]/i and safe | |
| 70 | * urls if allowed and cid urls if mapped are kept. | |
| 71 | * | |
| 72 | * Roundcube Changes: | |
| 73 | * - added $block_elements | |
| 74 | * - changed $ignore_elements behaviour | |
| 75 | * - added RFC2397 support | |
| 76 | * - base URL support | |
| 77 | * - invalid HTML comments removal before parsing | |
| 78 | * - "fixing" unitless CSS values for XHTML output | |
| 79 | * - base url resolving | |
| 80 | */ | |
| 81 | ||
| 82 | /** | |
| 83 | * Utility class providing HTML sanityzer | |
| 84 | * | |
| 85 | * @package Framework | |
| 86 | * @subpackage Utils | |
| 87 | */ | |
| 88 | class rcube_washtml | |
| 89 | { | |
| 90 | /* Allowed HTML elements (default) */ | |
| 91 | static $html_elements = array('a', 'abbr', 'acronym', 'address', 'area', 'b', | |
| 92 | 'basefont', 'bdo', 'big', 'blockquote', 'br', 'caption', 'center', | |
| 93 | 'cite', 'code', 'col', 'colgroup', 'dd', 'del', 'dfn', 'dir', 'div', 'dl', | |
| 94 | 'dt', 'em', 'fieldset', 'font', 'h1', 'h2', 'h3', 'h4', 'h5', 'h6', 'hr', 'i', | |
| 95 | 'ins', 'label', 'legend', 'li', 'map', 'menu', 'nobr', 'ol', 'p', 'pre', 'q', | |
| 96 | 's', 'samp', 'small', 'span', 'strike', 'strong', 'sub', 'sup', 'table', | |
| 97 | 'tbody', 'td', 'tfoot', 'th', 'thead', 'tr', 'tt', 'u', 'ul', 'var', 'wbr', 'img', | |
| 98 | // form elements | |
| ffd5ff | 99 | 'button', 'input', 'textarea', 'select', 'option', 'optgroup', |
| AM | 100 | // SVG |
| 73f8b5 | 101 | 'svg', 'altglyph', 'altglyphdef', 'altglyphitem', 'animate', |
| AM | 102 | 'animatecolor', 'animatetransform', 'circle', 'clippath', 'defs', 'desc', |
| ffd5ff | 103 | 'ellipse', 'font', 'g', 'glyph', 'glyphref', 'hkern', 'image', 'line', |
| AM | 104 | 'lineargradient', 'marker', 'mask', 'mpath', 'path', 'pattern', |
| 105 | 'polygon', 'polyline', 'radialgradient', 'rect', 'set', 'stop', 'switch', 'symbol', | |
| 106 | 'text', 'textpath', 'tref', 'tspan', 'use', 'view', 'vkern', 'filter', | |
| 107 | // SVG Filters | |
| 108 | 'feblend', 'fecolormatrix', 'fecomponenttransfer', 'fecomposite', | |
| 109 | 'feconvolvematrix', 'fediffuselighting', 'fedisplacementmap', | |
| 110 | 'feflood', 'fefunca', 'fefuncb', 'fefuncg', 'fefuncr', 'fegaussianblur', | |
| 111 | 'feimage', 'femerge', 'femergenode', 'femorphology', 'feoffset', | |
| 112 | 'fespecularlighting', 'fetile', 'feturbulence', | |
| 7ac944 | 113 | ); |
| AM | 114 | |
| 115 | /* Ignore these HTML tags and their content */ | |
| 116 | static $ignore_elements = array('script', 'applet', 'embed', 'object', 'style'); | |
| 117 | ||
| 118 | /* Allowed HTML attributes */ | |
| 119 | static $html_attribs = array('name', 'class', 'title', 'alt', 'width', 'height', | |
| 120 | 'align', 'nowrap', 'col', 'row', 'id', 'rowspan', 'colspan', 'cellspacing', | |
| 121 | 'cellpadding', 'valign', 'bgcolor', 'color', 'border', 'bordercolorlight', | |
| 122 | 'bordercolordark', 'face', 'marginwidth', 'marginheight', 'axis', 'border', | |
| 123 | 'abbr', 'char', 'charoff', 'clear', 'compact', 'coords', 'vspace', 'hspace', | |
| 124 | 'cellborder', 'size', 'lang', 'dir', 'usemap', 'shape', 'media', | |
| 190c65 | 125 | 'background', 'src', 'poster', 'href', |
| 7ac944 | 126 | // attributes of form elements |
| ffd5ff | 127 | 'type', 'rows', 'cols', 'disabled', 'readonly', 'checked', 'multiple', 'value', |
| AM | 128 | // SVG |
| 73f8b5 | 129 | 'accent-height', 'accumulate', 'additive', 'alignment-baseline', 'alphabetic', |
| ffd5ff | 130 | 'ascent', 'attributename', 'attributetype', 'azimuth', 'basefrequency', 'baseprofile', |
| AM | 131 | 'baseline-shift', 'begin', 'bias', 'by', 'clip', 'clip-path', 'clip-rule', |
| 132 | 'color', 'color-interpolation', 'color-interpolation-filters', 'color-profile', | |
| 133 | 'color-rendering', 'cx', 'cy', 'd', 'dx', 'dy', 'diffuseconstant', 'direction', | |
| 134 | 'display', 'divisor', 'dur', 'edgemode', 'elevation', 'end', 'fill', 'fill-opacity', | |
| 135 | 'fill-rule', 'filter', 'flood-color', 'flood-opacity', 'font-family', 'font-size', | |
| 190c65 | 136 | 'font-size-adjust', 'font-stretch', 'font-style', 'font-variant', 'font-weight', 'from', |
| ffd5ff | 137 | 'fx', 'fy', 'g1', 'g2', 'glyph-name', 'glyphref', 'gradientunits', 'gradienttransform', |
| AM | 138 | 'image-rendering', 'in', 'in2', 'k', 'k1', 'k2', 'k3', 'k4', 'kerning', 'keypoints', |
| 139 | 'keysplines', 'keytimes', 'lengthadjust', 'letter-spacing', 'kernelmatrix', | |
| 140 | 'kernelunitlength', 'lighting-color', 'local', 'marker-end', 'marker-mid', | |
| 141 | 'marker-start', 'markerheight', 'markerunits', 'markerwidth', 'maskcontentunits', | |
| 142 | 'maskunits', 'max', 'mask', 'mode', 'min', 'numoctaves', 'offset', 'operator', | |
| 143 | 'opacity', 'order', 'orient', 'orientation', 'origin', 'overflow', 'paint-order', | |
| 144 | 'path', 'pathlength', 'patterncontentunits', 'patterntransform', 'patternunits', | |
| 145 | 'points', 'preservealpha', 'r', 'rx', 'ry', 'radius', 'refx', 'refy', 'repeatcount', | |
| 73f8b5 | 146 | 'repeatdur', 'restart', 'rotate', 'scale', 'seed', 'shape-rendering', 'show', 'specularconstant', |
| ffd5ff | 147 | 'specularexponent', 'spreadmethod', 'stddeviation', 'stitchtiles', 'stop-color', |
| AM | 148 | 'stop-opacity', 'stroke-dasharray', 'stroke-dashoffset', 'stroke-linecap', |
| 149 | 'stroke-linejoin', 'stroke-miterlimit', 'stroke-opacity', 'stroke', 'stroke-width', | |
| 150 | 'surfacescale', 'targetx', 'targety', 'transform', 'text-anchor', 'text-decoration', | |
| 190c65 | 151 | 'text-rendering', 'textlength', 'to', 'u1', 'u2', 'unicode', 'values', 'viewbox', |
| ffd5ff | 152 | 'visibility', 'vert-adv-y', 'version', 'vert-origin-x', 'vert-origin-y', 'word-spacing', |
| AM | 153 | 'wrap', 'writing-mode', 'xchannelselector', 'ychannelselector', 'x', 'x1', 'x2', |
| 154 | 'xmlns', 'y', 'y1', 'y2', 'z', 'zoomandpan', | |
| 7ac944 | 155 | ); |
| AM | 156 | |
| cb3e2f | 157 | /* Elements which could be empty and be returned in short form (<tag />) */ |
| AM | 158 | static $void_elements = array('area', 'base', 'br', 'col', 'command', 'embed', 'hr', |
| ffd5ff | 159 | 'img', 'input', 'keygen', 'link', 'meta', 'param', 'source', 'track', 'wbr', |
| 7ac944 | 160 | ); |
| AM | 161 | |
| 162 | /* State for linked objects in HTML */ | |
| 163 | public $extlinks = false; | |
| 164 | ||
| 165 | /* Current settings */ | |
| 166 | private $config = array(); | |
| 167 | ||
| 168 | /* Registered callback functions for tags */ | |
| 169 | private $handlers = array(); | |
| 170 | ||
| 171 | /* Allowed HTML elements */ | |
| 172 | private $_html_elements = array(); | |
| 173 | ||
| 174 | /* Ignore these HTML tags but process their content */ | |
| 175 | private $_ignore_elements = array(); | |
| 176 | ||
| cb3e2f | 177 | /* Elements which could be empty and be returned in short form (<tag />) */ |
| AM | 178 | private $_void_elements = array(); |
| 7ac944 | 179 | |
| AM | 180 | /* Allowed HTML attributes */ |
| 181 | private $_html_attribs = array(); | |
| 182 | ||
| a89940 | 183 | /* Max nesting level */ |
| AM | 184 | private $max_nesting_level; |
| 73f8b5 | 185 | |
| AM | 186 | private $is_xml = false; |
| a89940 | 187 | |
| 7ac944 | 188 | |
| AM | 189 | /** |
| 190 | * Class constructor | |
| 191 | */ | |
| 192 | public function __construct($p = array()) | |
| 193 | { | |
| 190c65 | 194 | $this->_html_elements = array_flip((array)$p['html_elements']) + array_flip(self::$html_elements); |
| AM | 195 | $this->_html_attribs = array_flip((array)$p['html_attribs']) + array_flip(self::$html_attribs); |
| 196 | $this->_ignore_elements = array_flip((array)$p['ignore_elements']) + array_flip(self::$ignore_elements); | |
| 197 | $this->_void_elements = array_flip((array)$p['void_elements']) + array_flip(self::$void_elements); | |
| 7ac944 | 198 | |
| cb3e2f | 199 | unset($p['html_elements'], $p['html_attribs'], $p['ignore_elements'], $p['void_elements']); |
| 7ac944 | 200 | |
| AM | 201 | $this->config = $p + array('show_washed' => true, 'allow_remote' => false, 'cid_map' => array()); |
| 202 | } | |
| 203 | ||
| 204 | /** | |
| 205 | * Register a callback function for a certain tag | |
| 206 | */ | |
| 207 | public function add_callback($tagName, $callback) | |
| 208 | { | |
| 209 | $this->handlers[$tagName] = $callback; | |
| 210 | } | |
| 211 | ||
| 212 | /** | |
| 213 | * Check CSS style | |
| 214 | */ | |
| 215 | private function wash_style($style) | |
| 216 | { | |
| 05d419 | 217 | $result = array(); |
| 7ac944 | 218 | |
| AM | 219 | foreach (explode(';', $style) as $declaration) { |
| 220 | if (preg_match('/^\s*([a-z\-]+)\s*:\s*(.*)\s*$/i', $declaration, $match)) { | |
| 221 | $cssid = $match[1]; | |
| 222 | $str = $match[2]; | |
| 223 | $value = ''; | |
| 224 | ||
| 05d419 | 225 | foreach ($this->explode_style($str) as $val) { |
| AM | 226 | if (preg_match('/^url\(/i', $val)) { |
| 227 | if (preg_match('/^url\(\s*[\'"]?([^\'"\)]*)[\'"]?\s*\)/iu', $val, $match)) { | |
| 73f8b5 | 228 | if ($url = $this->wash_uri($match[1])) { |
| AM | 229 | $value .= ' url(' . htmlspecialchars($url, ENT_QUOTES) . ')'; |
| 05d419 | 230 | } |
| 7ac944 | 231 | } |
| AM | 232 | } |
| 05d419 | 233 | else if (!preg_match('/^(behavior|expression)/i', $val)) { |
| 7ac944 | 234 | // whitelist ? |
| 05d419 | 235 | $value .= ' ' . $val; |
| 7ac944 | 236 | |
| AM | 237 | // #1488535: Fix size units, so width:800 would be changed to width:800px |
| 49e260 | 238 | if (preg_match('/^(left|right|top|bottom|width|height)/i', $cssid) |
| 05d419 | 239 | && preg_match('/^[0-9]+$/', $val) |
| 7ac944 | 240 | ) { |
| AM | 241 | $value .= 'px'; |
| 242 | } | |
| 243 | } | |
| 244 | } | |
| 245 | ||
| 246 | if (isset($value[0])) { | |
| 05d419 | 247 | $result[] = $cssid . ':' . $value; |
| 7ac944 | 248 | } |
| AM | 249 | } |
| 250 | } | |
| 251 | ||
| 05d419 | 252 | return implode('; ', $result); |
| 7ac944 | 253 | } |
| AM | 254 | |
| 255 | /** | |
| 256 | * Take a node and return allowed attributes and check values | |
| 257 | */ | |
| 258 | private function wash_attribs($node) | |
| 259 | { | |
| 190c65 | 260 | $result = ''; |
| AM | 261 | $washed = array(); |
| 7ac944 | 262 | |
| ffd5ff | 263 | foreach ($node->attributes as $name => $attr) { |
| AM | 264 | $key = strtolower($name); |
| 265 | $value = $attr->nodeValue; | |
| 7ac944 | 266 | |
| 190c65 | 267 | if ($key == 'style' && ($style = $this->wash_style($value))) { |
| 049940 | 268 | // replace double quotes to prevent syntax error and XSS issues (#1490227) |
| 190c65 | 269 | $result .= ' style="' . str_replace('"', '"', $style) . '"'; |
| 7ac944 | 270 | } |
| 190c65 | 271 | else if (isset($this->_html_attribs[$key])) { |
| AM | 272 | $value = trim($value); |
| 73f8b5 | 273 | $out = null; |
| 190c65 | 274 | |
| 73f8b5 | 275 | // in SVG to/from attribs may contain anything, including URIs |
| AM | 276 | if ($key == 'to' || $key == 'from') { |
| 277 | $key = strtolower($node->getAttribute('attributeName')); | |
| 278 | if ($key && !isset($this->_html_attribs[$key])) { | |
| 279 | $key = null; | |
| 190c65 | 280 | } |
| 7ac944 | 281 | } |
| 73f8b5 | 282 | |
| AM | 283 | if ($this->is_image_attribute($node->tagName, $key)) { |
| 284 | $out = $this->wash_uri($value, true); | |
| 285 | } | |
| 286 | else if ($this->is_link_attribute($node->tagName, $key)) { | |
| 190c65 | 287 | if (!preg_match('!^(javascript|vbscript|data:text)!i', $value) |
| AM | 288 | && preg_match('!^([a-z][a-z0-9.+-]+:|//|#).+!i', $value) |
| 289 | ) { | |
| 290 | $out = $value; | |
| 291 | } | |
| 292 | } | |
| 73f8b5 | 293 | else if ($this->is_funciri_attribute($node->tagName, $key)) { |
| AM | 294 | if (preg_match('/^[a-z:]*url\(/i', $val)) { |
| 295 | if (preg_match('/^([a-z:]*url)\(\s*[\'"]?([^\'"\)]*)[\'"]?\s*\)/iu', $value, $match)) { | |
| 296 | if ($url = $this->wash_uri($match[2])) { | |
| 297 | $result .= ' ' . $attr->nodeName . '="' . $match[1] . '(' . htmlspecialchars($url, ENT_QUOTES) . ')' | |
| 298 | . substr($val, strlen($match[0])) . '"'; | |
| 299 | continue; | |
| 300 | } | |
| 301 | } | |
| 302 | else { | |
| 303 | $out = $value; | |
| 304 | } | |
| 305 | } | |
| 306 | else { | |
| 307 | $out = $value; | |
| 308 | } | |
| 309 | } | |
| 310 | else if ($key) { | |
| 190c65 | 311 | $out = $value; |
| AM | 312 | } |
| 313 | ||
| 73f8b5 | 314 | if ($out !== null && $out !== '') { |
| AM | 315 | $result .= ' ' . $attr->nodeName . '="' . htmlspecialchars($out, ENT_QUOTES) . '"'; |
| 190c65 | 316 | } |
| AM | 317 | else if ($value) { |
| 318 | $washed[] = htmlspecialchars($attr->nodeName, ENT_QUOTES); | |
| 7ac944 | 319 | } |
| AM | 320 | } |
| 321 | else { | |
| 190c65 | 322 | $washed[] = htmlspecialchars($attr->nodeName, ENT_QUOTES); |
| 7ac944 | 323 | } |
| AM | 324 | } |
| 325 | ||
| 190c65 | 326 | if (!empty($washed) && $this->config['show_washed']) { |
| AM | 327 | $result .= ' x-washed="' . implode(' ', $washed) . '"'; |
| 328 | } | |
| 329 | ||
| 330 | return $result; | |
| 331 | } | |
| 332 | ||
| 333 | /** | |
| 73f8b5 | 334 | * Wash URI value |
| AM | 335 | */ |
| 336 | private function wash_uri($uri, $blocked_source = false) | |
| 337 | { | |
| 338 | if (($src = $this->config['cid_map'][$uri]) | |
| 339 | || ($src = $this->config['cid_map'][$this->config['base_url'].$uri]) | |
| 340 | ) { | |
| 341 | return $src; | |
| 342 | } | |
| 343 | ||
| 344 | // allow url(#id) used in SVG | |
| 345 | if ($uri[0] == '#') { | |
| 346 | return $uri; | |
| 347 | } | |
| 348 | ||
| 349 | if (preg_match('/^(http|https|ftp):.+/i', $uri)) { | |
| 350 | if ($this->config['allow_remote']) { | |
| 351 | return $uri; | |
| 352 | } | |
| 353 | ||
| 354 | $this->extlinks = true; | |
| 355 | if ($blocked_source && $this->config['blocked_src']) { | |
| 356 | return $this->config['blocked_src']; | |
| 357 | } | |
| 358 | } | |
| 359 | else if (preg_match('/^data:image.+/i', $uri)) { // RFC2397 | |
| 360 | return $uri; | |
| 361 | } | |
| 362 | } | |
| 363 | ||
| 364 | /** | |
| 190c65 | 365 | * Check it the tag/attribute may contain an URI |
| AM | 366 | */ |
| 73f8b5 | 367 | private function is_link_attribute($tag, $attr) |
| 190c65 | 368 | { |
| acf633 | 369 | return ($tag == 'a' || $tag == 'area') && $attr == 'href'; |
| 190c65 | 370 | } |
| AM | 371 | |
| 372 | /** | |
| 373 | * Check it the tag/attribute may contain an image URI | |
| 374 | */ | |
| 73f8b5 | 375 | private function is_image_attribute($tag, $attr) |
| 190c65 | 376 | { |
| AM | 377 | return $attr == 'background' |
| 73f8b5 | 378 | || $attr == 'color-profile' // SVG |
| 190c65 | 379 | || ($attr == 'poster' && $tag == 'video') |
| 73f8b5 | 380 | || ($attr == 'src' && preg_match('/^(img|source)$/i', $tag)) |
| AM | 381 | || ($tag == 'image' && $attr == 'href'); // SVG |
| 382 | } | |
| 383 | ||
| 384 | /** | |
| 385 | * Check it the tag/attribute may contain a FUNCIRI value | |
| 386 | */ | |
| 387 | private function is_funciri_attribute($tag, $attr) | |
| 388 | { | |
| 389 | return in_array($attr, array('fill', 'filter', 'stroke', 'marker-start', | |
| 390 | 'marker-end', 'marker-mid', 'clip-path', 'mask', 'cursor')); | |
| 7ac944 | 391 | } |
| AM | 392 | |
| 393 | /** | |
| 394 | * The main loop that recurse on a node tree. | |
| 7883ec | 395 | * It output only allowed tags with allowed attributes and allowed inline styles |
| AM | 396 | * |
| 397 | * @param DOMNode $node HTML element | |
| 398 | * @param int $level Recurrence level (safe initial value found empirically) | |
| 7ac944 | 399 | */ |
| 7883ec | 400 | private function dumpHtml($node, $level = 20) |
| 7ac944 | 401 | { |
| AM | 402 | if (!$node->hasChildNodes()) { |
| 403 | return ''; | |
| a89940 | 404 | } |
| AM | 405 | |
| 406 | $level++; | |
| 407 | ||
| 408 | if ($this->max_nesting_level > 0 && $level == $this->max_nesting_level - 1) { | |
| 409 | // log error message once | |
| 410 | if (!$this->max_nesting_level_error) { | |
| 411 | $this->max_nesting_level_error = true; | |
| 412 | rcube::raise_error(array('code' => 500, 'type' => 'php', | |
| 413 | 'line' => __LINE__, 'file' => __FILE__, | |
| 414 | 'message' => "Maximum nesting level exceeded (xdebug.max_nesting_level={$this->max_nesting_level})"), | |
| 415 | true, false); | |
| 416 | } | |
| 417 | return '<!-- ignored -->'; | |
| 7ac944 | 418 | } |
| AM | 419 | |
| 420 | $node = $node->firstChild; | |
| 421 | $dump = ''; | |
| 422 | ||
| 423 | do { | |
| e7d1a8 | 424 | switch ($node->nodeType) { |
| 7ac944 | 425 | case XML_ELEMENT_NODE: //Check element |
| AM | 426 | $tagName = strtolower($node->tagName); |
| 427 | if ($callback = $this->handlers[$tagName]) { | |
| 428 | $dump .= call_user_func($callback, $tagName, | |
| a89940 | 429 | $this->wash_attribs($node), $this->dumpHtml($node, $level), $this); |
| 7ac944 | 430 | } |
| AM | 431 | else if (isset($this->_html_elements[$tagName])) { |
| a89940 | 432 | $content = $this->dumpHtml($node, $level); |
| 73f8b5 | 433 | $dump .= '<' . $node->tagName; |
| ffd5ff | 434 | |
| AM | 435 | if ($tagName == 'svg') { |
| 436 | $xpath = new DOMXPath($node->ownerDocument); | |
| 437 | foreach ($xpath->query('namespace::*') as $ns) { | |
| 438 | if ($ns->nodeName != 'xmlns:xml') { | |
| 439 | $dump .= ' ' . $ns->nodeName . '="' . $ns->nodeValue . '"'; | |
| 440 | } | |
| 441 | } | |
| 442 | } | |
| 443 | ||
| 444 | $dump .= $this->wash_attribs($node); | |
| 445 | ||
| 73f8b5 | 446 | if ($content === '' && ($this->is_xml || isset($this->_void_elements[$tagName]))) { |
| ffd5ff | 447 | $dump .= ' />'; |
| AM | 448 | } |
| 449 | else { | |
| 73f8b5 | 450 | $dump .= '>' . $content . '</' . $node->tagName . '>'; |
| ffd5ff | 451 | } |
| 7ac944 | 452 | } |
| AM | 453 | else if (isset($this->_ignore_elements[$tagName])) { |
| 73f8b5 | 454 | $dump .= '<!-- ' . htmlspecialchars($node->tagName, ENT_QUOTES) . ' not allowed -->'; |
| 7ac944 | 455 | } |
| AM | 456 | else { |
| 73f8b5 | 457 | $dump .= '<!-- ' . htmlspecialchars($node->tagName, ENT_QUOTES) . ' ignored -->'; |
| a89940 | 458 | $dump .= $this->dumpHtml($node, $level); // ignore tags not its content |
| 7ac944 | 459 | } |
| AM | 460 | break; |
| 461 | ||
| 462 | case XML_CDATA_SECTION_NODE: | |
| 463 | $dump .= $node->nodeValue; | |
| 464 | break; | |
| 465 | ||
| 466 | case XML_TEXT_NODE: | |
| 467 | $dump .= htmlspecialchars($node->nodeValue); | |
| 468 | break; | |
| 469 | ||
| 470 | case XML_HTML_DOCUMENT_NODE: | |
| a89940 | 471 | $dump .= $this->dumpHtml($node, $level); |
| 7ac944 | 472 | break; |
| AM | 473 | } |
| e7d1a8 | 474 | } |
| AM | 475 | while($node = $node->nextSibling); |
| 7ac944 | 476 | |
| AM | 477 | return $dump; |
| 478 | } | |
| 479 | ||
| 480 | /** | |
| 481 | * Main function, give it untrusted HTML, tell it if you allow loading | |
| 482 | * remote images and give it a map to convert "cid:" urls. | |
| 483 | */ | |
| 484 | public function wash($html) | |
| 485 | { | |
| 486 | // Charset seems to be ignored (probably if defined in the HTML document) | |
| 487 | $node = new DOMDocument('1.0', $this->config['charset']); | |
| 488 | $this->extlinks = false; | |
| 489 | ||
| 490 | $html = $this->cleanup($html); | |
| 491 | ||
| 492 | // Find base URL for images | |
| 493 | if (preg_match('/<base\s+href=[\'"]*([^\'"]+)/is', $html, $matches)) { | |
| 494 | $this->config['base_url'] = $matches[1]; | |
| 495 | } | |
| 496 | else { | |
| 497 | $this->config['base_url'] = ''; | |
| 498 | } | |
| a89940 | 499 | |
| AM | 500 | // Detect max nesting level (for dumpHTML) (#1489110) |
| 501 | $this->max_nesting_level = (int) @ini_get('xdebug.max_nesting_level'); | |
| 7ac944 | 502 | |
| ffd5ff | 503 | // SVG need to be parsed as XML |
| 889989 | 504 | $this->is_xml = stripos($html, '<html') === false && stripos($html, '<svg') !== false; |
| 73f8b5 | 505 | $method = $this->is_xml ? 'loadXML' : 'loadHTML'; |
| AM | 506 | $options = 0; |
| ffd5ff | 507 | |
| bfd24f | 508 | // Use optimizations if supported |
| ffd5ff | 509 | if (PHP_VERSION_ID >= 50400) { |
| AM | 510 | $options = LIBXML_PARSEHUGE | LIBXML_COMPACT | LIBXML_NONET; |
| 190c65 | 511 | @$node->{$method}($html, $options); |
| bfd24f | 512 | } |
| 190c65 | 513 | else { |
| AM | 514 | @$node->{$method}($html); |
| 515 | } | |
| bfd24f | 516 | |
| 7ac944 | 517 | return $this->dumpHtml($node); |
| AM | 518 | } |
| 519 | ||
| 520 | /** | |
| 521 | * Getter for config parameters | |
| 522 | */ | |
| 523 | public function get_config($prop) | |
| 524 | { | |
| 525 | return $this->config[$prop]; | |
| 526 | } | |
| 527 | ||
| 528 | /** | |
| 529 | * Clean HTML input | |
| 530 | */ | |
| 531 | private function cleanup($html) | |
| 532 | { | |
| ffd5ff | 533 | $html = trim($html); |
| AM | 534 | |
| 7ac944 | 535 | // special replacements (not properly handled by washtml class) |
| AM | 536 | $html_search = array( |
| 537 | '/(<\/nobr>)(\s+)(<nobr>)/i', // space(s) between <NOBR> | |
| 538 | '/<title[^>]*>[^<]*<\/title>/i', // PHP bug #32547 workaround: remove title tag | |
| 539 | '/^(\0\0\xFE\xFF|\xFF\xFE\0\0|\xFE\xFF|\xFF\xFE|\xEF\xBB\xBF)/', // byte-order mark (only outlook?) | |
| 540 | '/<html\s[^>]+>/i', // washtml/DOMDocument cannot handle xml namespaces | |
| 541 | ); | |
| 542 | ||
| 543 | $html_replace = array( | |
| 544 | '\\1'.' '.'\\3', | |
| 545 | '', | |
| 546 | '', | |
| 547 | '<html>', | |
| 548 | ); | |
| ffd5ff | 549 | |
| 7ac944 | 550 | $html = preg_replace($html_search, $html_replace, trim($html)); |
| AM | 551 | |
| ffd5ff | 552 | // Replace all of those weird MS Word quotes and other high characters |
| c72507 | 553 | $badwordchars = array( |
| b6a640 | 554 | "\xe2\x80\x98", // left single quote |
| R | 555 | "\xe2\x80\x99", // right single quote |
| 556 | "\xe2\x80\x9c", // left double quote | |
| 557 | "\xe2\x80\x9d", // right double quote | |
| 558 | "\xe2\x80\x94", // em dash | |
| ffd5ff | 559 | "\xe2\x80\xa6" // elipses |
| b6a640 | 560 | ); |
| ffd5ff | 561 | |
| c72507 | 562 | $fixedwordchars = array( |
| b6a640 | 563 | "'", |
| R | 564 | "'", |
| 565 | '"', | |
| 566 | '"', | |
| 567 | '—', | |
| 568 | '...' | |
| 569 | ); | |
| ffd5ff | 570 | |
| c72507 | 571 | $html = str_replace($badwordchars, $fixedwordchars, $html); |
| b6a640 | 572 | |
| 7ac944 | 573 | // PCRE errors handling (#1486856), should we use something like for every preg_* use? |
| AM | 574 | if ($html === null && ($preg_error = preg_last_error()) != PREG_NO_ERROR) { |
| 575 | $errstr = "Could not clean up HTML message! PCRE Error: $preg_error."; | |
| 576 | ||
| 577 | if ($preg_error == PREG_BACKTRACK_LIMIT_ERROR) { | |
| 578 | $errstr .= " Consider raising pcre.backtrack_limit!"; | |
| 579 | } | |
| 580 | if ($preg_error == PREG_RECURSION_LIMIT_ERROR) { | |
| 581 | $errstr .= " Consider raising pcre.recursion_limit!"; | |
| 582 | } | |
| 583 | ||
| 584 | rcube::raise_error(array('code' => 620, 'type' => 'php', | |
| 585 | 'line' => __LINE__, 'file' => __FILE__, | |
| 586 | 'message' => $errstr), true, false); | |
| a89940 | 587 | |
| 7ac944 | 588 | return ''; |
| AM | 589 | } |
| 590 | ||
| 591 | // fix (unknown/malformed) HTML tags before "wash" | |
| ffec85 | 592 | $html = preg_replace_callback('/(<(?!\!)[\/]*)([^\s>]+)([^>]*)/', array($this, 'html_tag_callback'), $html); |
| 7ac944 | 593 | |
| AM | 594 | // Remove invalid HTML comments (#1487759) |
| 595 | // Don't remove valid conditional comments | |
| 1bce14 | 596 | // Don't remove MSOutlook (<!-->) conditional comments (#1489004) |
| 2d233b | 597 | $html = preg_replace('/<!--[^-<>\[\n]+>/', '', $html); |
| c72507 | 598 | |
| AM | 599 | // fix broken nested lists |
| 600 | self::fix_broken_lists($html); | |
| 7ac944 | 601 | |
| AM | 602 | // turn relative into absolute urls |
| 603 | $html = self::resolve_base($html); | |
| 604 | ||
| 605 | return $html; | |
| 606 | } | |
| 607 | ||
| 608 | /** | |
| 609 | * Callback function for HTML tags fixing | |
| 610 | */ | |
| 611 | public static function html_tag_callback($matches) | |
| 612 | { | |
| 613 | $tagname = $matches[2]; | |
| 614 | $tagname = preg_replace(array( | |
| 615 | '/:.*$/', // Microsoft's Smart Tags <st1:xxxx> | |
| ffd5ff | 616 | '/[^a-z0-9_\[\]\!?-]/i', // forbidden characters |
| 7ac944 | 617 | ), '', $tagname); |
| AM | 618 | |
| ffec85 | 619 | // fix invalid closing tags - remove any attributes (#1489446) |
| AM | 620 | if ($matches[1] == '</') { |
| 621 | $matches[3] = ''; | |
| 622 | } | |
| 623 | ||
| 624 | return $matches[1] . $tagname . $matches[3]; | |
| 7ac944 | 625 | } |
| AM | 626 | |
| 627 | /** | |
| 628 | * Convert all relative URLs according to a <base> in HTML | |
| 629 | */ | |
| 630 | public static function resolve_base($body) | |
| 631 | { | |
| 632 | // check for <base href=...> | |
| 633 | if (preg_match('!(<base.*href=["\']?)([hftps]{3,5}://[a-z0-9/.%-]+)!i', $body, $regs)) { | |
| 634 | $replacer = new rcube_base_replacer($regs[2]); | |
| 635 | $body = $replacer->replace($body); | |
| 636 | } | |
| 637 | ||
| 638 | return $body; | |
| 639 | } | |
| 640 | ||
| c72507 | 641 | /** |
| AM | 642 | * Fix broken nested lists, they are not handled properly by DOMDocument (#1488768) |
| 643 | */ | |
| 644 | public static function fix_broken_lists(&$html) | |
| 645 | { | |
| 646 | // do two rounds, one for <ol>, one for <ul> | |
| 647 | foreach (array('ol', 'ul') as $tag) { | |
| 648 | $pos = 0; | |
| 649 | while (($pos = stripos($html, '<' . $tag, $pos)) !== false) { | |
| 650 | $pos++; | |
| 651 | ||
| 652 | // make sure this is an ol/ul tag | |
| 653 | if (!in_array($html[$pos+2], array(' ', '>'))) { | |
| 654 | continue; | |
| 655 | } | |
| 656 | ||
| 657 | $p = $pos; | |
| 658 | $in_li = false; | |
| 659 | $li_pos = 0; | |
| 660 | ||
| 661 | while (($p = strpos($html, '<', $p)) !== false) { | |
| 662 | $tt = strtolower(substr($html, $p, 4)); | |
| 663 | ||
| 664 | // li open tag | |
| 665 | if ($tt == '<li>' || $tt == '<li ') { | |
| 666 | $in_li = true; | |
| 667 | $p += 4; | |
| 668 | } | |
| 669 | // li close tag | |
| 670 | else if ($tt == '</li' && in_array($html[$p+4], array(' ', '>'))) { | |
| 671 | $li_pos = $p; | |
| 672 | $p += 4; | |
| 673 | $in_li = false; | |
| 674 | } | |
| 675 | // ul/ol closing tag | |
| 676 | else if ($tt == '</' . $tag && in_array($html[$p+4], array(' ', '>'))) { | |
| 677 | break; | |
| 678 | } | |
| 679 | // nested ol/ul element out of li | |
| 680 | else if (!$in_li && $li_pos && ($tt == '<ol>' || $tt == '<ol ' || $tt == '<ul>' || $tt == '<ul ')) { | |
| 681 | // find closing tag of this ul/ol element | |
| 682 | $element = substr($tt, 1, 2); | |
| 683 | $cpos = $p; | |
| 684 | do { | |
| 685 | $tpos = stripos($html, '<' . $element, $cpos+1); | |
| 686 | $cpos = stripos($html, '</' . $element, $cpos+1); | |
| 687 | } | |
| 688 | while ($tpos !== false && $cpos !== false && $cpos > $tpos); | |
| 689 | ||
| 690 | // not found, this is invalid HTML, skip it | |
| 691 | if ($cpos === false) { | |
| 692 | break; | |
| 693 | } | |
| 694 | ||
| 695 | // get element content | |
| 696 | $end = strpos($html, '>', $cpos); | |
| 697 | $len = $end - $p + 1; | |
| 698 | $element = substr($html, $p, $len); | |
| 699 | ||
| 700 | // move element to the end of the last li | |
| 701 | $html = substr_replace($html, '', $p, $len); | |
| 702 | $html = substr_replace($html, $element, $li_pos, 0); | |
| 703 | ||
| 704 | $p = $end; | |
| 705 | } | |
| 706 | else { | |
| 707 | $p++; | |
| 708 | } | |
| 709 | } | |
| 710 | } | |
| 711 | } | |
| 712 | } | |
| 05d419 | 713 | |
| AM | 714 | /** |
| 715 | * Explode css style value | |
| 716 | */ | |
| 717 | protected function explode_style($style) | |
| 718 | { | |
| 719 | $style = trim($style); | |
| 720 | ||
| 721 | // first remove comments | |
| 722 | $pos = 0; | |
| 723 | while (($pos = strpos($style, '/*', $pos)) !== false) { | |
| 724 | $end = strpos($style, '*/', $pos+2); | |
| 725 | ||
| 726 | if ($end === false) { | |
| 727 | $style = substr($style, 0, $pos); | |
| 728 | } | |
| 729 | else { | |
| 730 | $style = substr_replace($style, '', $pos, $end - $pos + 2); | |
| 731 | } | |
| 732 | } | |
| 733 | ||
| 734 | $strlen = strlen($style); | |
| 735 | $result = array(); | |
| 736 | ||
| 737 | // explode value | |
| 738 | for ($p=$i=0; $i < $strlen; $i++) { | |
| 739 | if (($style[$i] == "\"" || $style[$i] == "'") && $style[$i-1] != "\\") { | |
| 740 | if ($q == $style[$i]) { | |
| 741 | $q = false; | |
| 742 | } | |
| 743 | else if (!$q) { | |
| 744 | $q = $style[$i]; | |
| 745 | } | |
| 746 | } | |
| 747 | ||
| 748 | if (!$q && $style[$i] == ' ' && !preg_match('/[,\(]/', $style[$i-1])) { | |
| 749 | $result[] = substr($style, $p, $i - $p); | |
| 750 | $p = $i + 1; | |
| 751 | } | |
| 752 | } | |
| 753 | ||
| 754 | $result[] = (string) substr($style, $p); | |
| 755 | ||
| 756 | return $result; | |
| 757 | } | |
| c72507 | 758 | } |
