forked from science-ation/science-ation
862 lines
22 KiB
PHP
862 lines
22 KiB
PHP
<?php
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/**
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* htmlfilter.inc
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* ---------------
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* This set of functions allows you to filter html in order to remove
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* any malicious tags from it. Useful in cases when you need to filter
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* user input for any cross-site-scripting attempts.
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*
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* Copyright (C) 2002-2004 by Duke University
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*
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* This library is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2.1 of the License, or (at your option) any later version.
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*
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* This library is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with this library; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
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* 02110-1301 USA
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*
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* @Author Konstantin Riabitsev <icon@linux.duke.edu>
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* @Version 1.1 ($Date: 2011-07-04 14:02:23 -0400 (Mon, 04 Jul 2011) $)
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*/
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/**
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* @Author Jim Jagielski <jim@jaguNET.com / jimjag@gmail.com>
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*/
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/**
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* This function returns the final tag out of the tag name, an array
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* of attributes, and the type of the tag. This function is called by
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* tln_sanitize internally.
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*
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* @param $tagname the name of the tag.
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* @param $attary the array of attributes and their values
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* @param $tagtype The type of the tag (see in comments).
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* @return a string with the final tag representation.
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*/
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function tln_tagprint($tagname, $attary, $tagtype){
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$me = 'tln_tagprint';
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if ($tagtype == 2){
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$fulltag = '</' . $tagname . '>';
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} else {
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$fulltag = '<' . $tagname;
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if (is_array($attary) && sizeof($attary)){
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$atts = Array();
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while (list($attname, $attvalue) = each($attary)){
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array_push($atts, "$attname=$attvalue");
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}
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$fulltag .= ' ' . join(' ', $atts);
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}
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if ($tagtype == 3){
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$fulltag .= ' /';
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}
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$fulltag .= '>';
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}
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return $fulltag;
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}
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/**
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* A small helper function to use with array_walk. Modifies a by-ref
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* value and makes it lowercase.
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*
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* @param $val a value passed by-ref.
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* @return void since it modifies a by-ref value.
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*/
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function tln_casenormalize(&$val){
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$val = strtolower($val);
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}
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/**
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* This function skips any whitespace from the current position within
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* a string and to the next non-whitespace value.
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*
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* @param $body the string
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* @param $offset the offset within the string where we should start
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* looking for the next non-whitespace character.
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* @return the location within the $body where the next
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* non-whitespace char is located.
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*/
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function tln_skipspace($body, $offset){
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$me = 'tln_skipspace';
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preg_match('/^(\s*)/s', substr($body, $offset), $matches);
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if (sizeof($matches[1])){
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$count = strlen($matches[1]);
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$offset += $count;
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}
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return $offset;
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}
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/**
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* This function looks for the next character within a string. It's
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* really just a glorified "strpos", except it catches the failures
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* nicely.
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*
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* @param $body The string to look for needle in.
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* @param $offset Start looking from this position.
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* @param $needle The character/string to look for.
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* @return location of the next occurrence of the needle, or
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* strlen($body) if needle wasn't found.
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*/
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function tln_findnxstr($body, $offset, $needle){
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$me = 'tln_findnxstr';
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$pos = strpos($body, $needle, $offset);
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if ($pos === FALSE){
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$pos = strlen($body);
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}
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return $pos;
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}
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/**
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* This function takes a PCRE-style regexp and tries to match it
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* within the string.
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*
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* @param $body The string to look for needle in.
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* @param $offset Start looking from here.
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* @param $reg A PCRE-style regex to match.
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* @return Returns a false if no matches found, or an array
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* with the following members:
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* - integer with the location of the match within $body
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* - string with whatever content between offset and the match
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* - string with whatever it is we matched
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*/
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function tln_findnxreg($body, $offset, $reg){
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$me = 'tln_findnxreg';
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$matches = Array();
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$retarr = Array();
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$preg_rule = '%^(.*?)(' . $reg . ')%s';
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preg_match($preg_rule, substr($body, $offset), $matches);
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if (!isset($matches[0])){
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$retarr = false;
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} else {
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$retarr[0] = $offset + strlen($matches[1]);
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$retarr[1] = $matches[1];
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$retarr[2] = $matches[2];
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}
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return $retarr;
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}
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/**
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* This function looks for the next tag.
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*
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* @param $body String where to look for the next tag.
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* @param $offset Start looking from here.
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* @return false if no more tags exist in the body, or
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* an array with the following members:
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* - string with the name of the tag
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* - array with attributes and their values
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* - integer with tag type (1, 2, or 3)
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* - integer where the tag starts (starting "<")
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* - integer where the tag ends (ending ">")
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* first three members will be false, if the tag is invalid.
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*/
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function tln_getnxtag($body, $offset){
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$me = 'tln_getnxtag';
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if ($offset > strlen($body)){
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return false;
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}
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$lt = tln_findnxstr($body, $offset, '<');
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if ($lt == strlen($body)){
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return false;
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}
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/**
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* We are here:
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* blah blah <tag attribute="value">
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* \---------^
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*/
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$pos = tln_skipspace($body, $lt + 1);
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if ($pos >= strlen($body)){
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return Array(false, false, false, $lt, strlen($body));
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}
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/**
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* There are 3 kinds of tags:
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* 1. Opening tag, e.g.:
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* <a href="blah">
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* 2. Closing tag, e.g.:
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* </a>
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* 3. XHTML-style content-less tag, e.g.:
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* <img src="blah"/>
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*/
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$tagtype = false;
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switch (substr($body, $pos, 1)){
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case '/':
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$tagtype = 2;
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$pos++;
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break;
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case '!':
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/**
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* A comment or an SGML declaration.
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*/
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if (substr($body, $pos+1, 2) == '--'){
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$gt = strpos($body, '-->', $pos);
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if ($gt === false){
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$gt = strlen($body);
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} else {
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$gt += 2;
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}
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return Array(false, false, false, $lt, $gt);
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} else {
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$gt = tln_findnxstr($body, $pos, '>');
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return Array(false, false, false, $lt, $gt);
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}
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break;
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default:
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/**
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* Assume tagtype 1 for now. If it's type 3, we'll switch values
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* later.
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*/
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$tagtype = 1;
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break;
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}
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$tag_start = $pos;
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$tagname = '';
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/**
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* Look for next [\W-_], which will indicate the end of the tag name.
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*/
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$regary = tln_findnxreg($body, $pos, '[^\w\-_]');
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if ($regary == false){
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return Array(false, false, false, $lt, strlen($body));
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}
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list($pos, $tagname, $match) = $regary;
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$tagname = strtolower($tagname);
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/**
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* $match can be either of these:
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* '>' indicating the end of the tag entirely.
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* '\s' indicating the end of the tag name.
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* '/' indicating that this is type-3 xhtml tag.
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*
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* Whatever else we find there indicates an invalid tag.
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*/
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switch ($match){
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case '/':
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/**
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* This is an xhtml-style tag with a closing / at the
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* end, like so: <img src="blah"/>. Check if it's followed
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* by the closing bracket. If not, then this tag is invalid
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*/
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if (substr($body, $pos, 2) == '/>'){
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$pos++;
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$tagtype = 3;
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} else {
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$gt = tln_findnxstr($body, $pos, '>');
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$retary = Array(false, false, false, $lt, $gt);
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return $retary;
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}
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case '>':
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return Array($tagname, false, $tagtype, $lt, $pos);
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break;
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default:
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/**
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* Check if it's whitespace
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*/
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if (preg_match('/\s/', $match)){
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} else {
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/**
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* This is an invalid tag! Look for the next closing ">".
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*/
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$gt = tln_findnxstr($body, $lt, '>');
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return Array(false, false, false, $lt, $gt);
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}
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}
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/**
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* At this point we're here:
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* <tagname attribute='blah'>
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* \-------^
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*
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* At this point we loop in order to find all attributes.
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*/
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$attname = '';
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$atttype = false;
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$attary = Array();
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while ($pos <= strlen($body)){
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$pos = tln_skipspace($body, $pos);
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if ($pos == strlen($body)){
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/**
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* Non-closed tag.
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*/
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return Array(false, false, false, $lt, $pos);
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}
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/**
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* See if we arrived at a ">" or "/>", which means that we reached
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* the end of the tag.
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*/
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$matches = Array();
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preg_match('%^(\s*)(>|/>)%s', substr($body, $pos), $matches);
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if (isset($matches[0]) && $matches[0]){
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/**
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* Yep. So we did.
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*/
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$pos += strlen($matches[1]);
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if ($matches[2] == '/>'){
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$tagtype = 3;
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$pos++;
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}
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return Array($tagname, $attary, $tagtype, $lt, $pos);
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}
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/**
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* There are several types of attributes, with optional
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* [:space:] between members.
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* Type 1:
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* attrname[:space:]=[:space:]'CDATA'
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* Type 2:
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* attrname[:space:]=[:space:]"CDATA"
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* Type 3:
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* attr[:space:]=[:space:]CDATA
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* Type 4:
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* attrname
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*
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* We leave types 1 and 2 the same, type 3 we check for
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* '"' and convert to """ if needed, then wrap in
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* double quotes. Type 4 we convert into:
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* attrname="yes".
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*/
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$regary = tln_findnxreg($body, $pos, '[^\w\-_]');
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if ($regary == false){
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/**
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* Looks like body ended before the end of tag.
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*/
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return Array(false, false, false, $lt, strlen($body));
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}
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list($pos, $attname, $match) = $regary;
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$attname = strtolower($attname);
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/**
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* We arrived at the end of attribute name. Several things possible
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* here:
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* '>' means the end of the tag and this is attribute type 4
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* '/' if followed by '>' means the same thing as above
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* '\s' means a lot of things -- look what it's followed by.
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* anything else means the attribute is invalid.
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*/
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switch($match){
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case '/':
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/**
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* This is an xhtml-style tag with a closing / at the
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* end, like so: <img src="blah"/>. Check if it's followed
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* by the closing bracket. If not, then this tag is invalid
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*/
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if (substr($body, $pos, 2) == '/>'){
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$pos++;
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$tagtype = 3;
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} else {
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$gt = tln_findnxstr($body, $pos, '>');
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$retary = Array(false, false, false, $lt, $gt);
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return $retary;
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}
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case '>':
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$attary{$attname} = '"yes"';
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return Array($tagname, $attary, $tagtype, $lt, $pos);
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break;
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default:
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/**
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* Skip whitespace and see what we arrive at.
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*/
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$pos = tln_skipspace($body, $pos);
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$char = substr($body, $pos, 1);
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/**
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* Two things are valid here:
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* '=' means this is attribute type 1 2 or 3.
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* \w means this was attribute type 4.
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* anything else we ignore and re-loop. End of tag and
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* invalid stuff will be caught by our checks at the beginning
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* of the loop.
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*/
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if ($char == '='){
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$pos++;
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$pos = tln_skipspace($body, $pos);
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/**
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* Here are 3 possibilities:
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* "'" attribute type 1
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* '"' attribute type 2
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* everything else is the content of tag type 3
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*/
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$quot = substr($body, $pos, 1);
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if ($quot == '\''){
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$regary = tln_findnxreg($body, $pos+1, '\'');
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if ($regary == false){
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return Array(false, false, false, $lt, strlen($body));
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}
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list($pos, $attval, $match) = $regary;
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$pos++;
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$attary{$attname} = '\'' . $attval . '\'';
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} else if ($quot == '"'){
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$regary = tln_findnxreg($body, $pos+1, '\"');
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if ($regary == false){
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return Array(false, false, false, $lt, strlen($body));
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}
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list($pos, $attval, $match) = $regary;
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$pos++;
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$attary{$attname} = '"' . $attval . '"';
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} else {
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/**
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* These are hateful. Look for \s, or >.
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*/
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$regary = tln_findnxreg($body, $pos, '[\s>]');
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if ($regary == false){
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return Array(false, false, false, $lt, strlen($body));
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}
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list($pos, $attval, $match) = $regary;
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/**
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* If it's ">" it will be caught at the top.
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*/
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$attval = preg_replace('/\"/s', '"', $attval);
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$attary{$attname} = '"' . $attval . '"';
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}
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} else if (preg_match('|[\w/>]|', $char)) {
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/**
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* That was attribute type 4.
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*/
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$attary{$attname} = '"yes"';
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} else {
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/**
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* An illegal character. Find next '>' and return.
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*/
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$gt = tln_findnxstr($body, $pos, '>');
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return Array(false, false, false, $lt, $gt);
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}
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}
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}
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/**
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* The fact that we got here indicates that the tag end was never
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* found. Return invalid tag indication so it gets stripped.
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*/
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return Array(false, false, false, $lt, strlen($body));
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}
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/**
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* Translates entities into literal values so they can be checked.
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*
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* @param $attvalue the by-ref value to check.
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* @param $regex the regular expression to check against.
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* @param $hex whether the entites are hexadecimal.
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* @return True or False depending on whether there were matches.
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*/
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function tln_deent(&$attvalue, $regex, $hex=false){
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$me = 'tln_deent';
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$ret_match = false;
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preg_match_all($regex, $attvalue, $matches);
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if (is_array($matches) && sizeof($matches[0]) > 0){
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$repl = Array();
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for ($i = 0; $i < sizeof($matches[0]); $i++){
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$numval = $matches[1][$i];
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if ($hex){
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$numval = hexdec($numval);
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}
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$repl{$matches[0][$i]} = chr($numval);
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}
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$attvalue = strtr($attvalue, $repl);
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return true;
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} else {
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return false;
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}
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}
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/**
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* This function checks attribute values for entity-encoded values
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* and returns them translated into 8-bit strings so we can run
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* checks on them.
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*
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* @param $attvalue A string to run entity check against.
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* @return Nothing, modifies a reference value.
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*/
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function tln_defang(&$attvalue){
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$me = 'tln_defang';
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/**
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* Skip this if there aren't ampersands or backslashes.
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*/
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if (strpos($attvalue, '&') === false
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&& strpos($attvalue, '\\') === false){
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return;
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}
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$m = false;
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do {
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$m = false;
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$m = $m || tln_deent($attvalue, '/\�*(\d+);*/s');
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$m = $m || tln_deent($attvalue, '/\�*((\d|[a-f])+);*/si', true);
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$m = $m || tln_deent($attvalue, '/\\\\(\d+)/s', true);
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} while ($m == true);
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$attvalue = stripslashes($attvalue);
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}
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/**
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* Kill any tabs, newlines, or carriage returns. Our friends the
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* makers of the browser with 95% market value decided that it'd
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* be funny to make "java[tab]script" be just as good as "javascript".
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*
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* @param attvalue The attribute value before extraneous spaces removed.
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* @return attvalue Nothing, modifies a reference value.
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*/
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function tln_unspace(&$attvalue){
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$me = 'tln_unspace';
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if (strcspn($attvalue, "\t\r\n\0 ") != strlen($attvalue)){
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$attvalue = str_replace(Array("\t", "\r", "\n", "\0", " "),
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Array('', '', '', '', ''), $attvalue);
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}
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}
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/**
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* This function runs various checks against the attributes.
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*
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* @param $tagname String with the name of the tag.
|
|
* @param $attary Array with all tag attributes.
|
|
* @param $rm_attnames See description for tln_sanitize
|
|
* @param $bad_attvals See description for tln_sanitize
|
|
* @param $add_attr_to_tag See description for tln_sanitize
|
|
* @return Array with modified attributes.
|
|
*/
|
|
function tln_fixatts($tagname,
|
|
$attary,
|
|
$rm_attnames,
|
|
$bad_attvals,
|
|
$add_attr_to_tag
|
|
){
|
|
$me = 'tln_fixatts';
|
|
while (list($attname, $attvalue) = each($attary)){
|
|
/**
|
|
* See if this attribute should be removed.
|
|
*/
|
|
foreach ($rm_attnames as $matchtag=>$matchattrs){
|
|
if (preg_match($matchtag, $tagname)){
|
|
foreach ($matchattrs as $matchattr){
|
|
if (preg_match($matchattr, $attname)){
|
|
unset($attary{$attname});
|
|
continue;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
/**
|
|
* Remove any backslashes, entities, or extraneous whitespace.
|
|
*/
|
|
tln_defang($attvalue);
|
|
tln_unspace($attvalue);
|
|
|
|
/**
|
|
* Now let's run checks on the attvalues.
|
|
* I don't expect anyone to comprehend this. If you do,
|
|
* get in touch with me so I can drive to where you live and
|
|
* shake your hand personally. :)
|
|
*/
|
|
foreach ($bad_attvals as $matchtag=>$matchattrs){
|
|
if (preg_match($matchtag, $tagname)){
|
|
foreach ($matchattrs as $matchattr=>$valary){
|
|
if (preg_match($matchattr, $attname)){
|
|
/**
|
|
* There are two arrays in valary.
|
|
* First is matches.
|
|
* Second one is replacements
|
|
*/
|
|
list($valmatch, $valrepl) = $valary;
|
|
$newvalue = preg_replace($valmatch,$valrepl,$attvalue);
|
|
if ($newvalue != $attvalue){
|
|
$attary{$attname} = $newvalue;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
/**
|
|
* See if we need to append any attributes to this tag.
|
|
*/
|
|
foreach ($add_attr_to_tag as $matchtag=>$addattary){
|
|
if (preg_match($matchtag, $tagname)){
|
|
$attary = array_merge($attary, $addattary);
|
|
}
|
|
}
|
|
return $attary;
|
|
}
|
|
|
|
/**
|
|
*
|
|
* @param $body the string with HTML you wish to filter
|
|
* @param $tag_list see description above
|
|
* @param $rm_tags_with_content see description above
|
|
* @param $self_closing_tags see description above
|
|
* @param $force_tag_closing see description above
|
|
* @param $rm_attnames see description above
|
|
* @param $bad_attvals see description above
|
|
* @param $add_attr_to_tag see description above
|
|
* @return tln_sanitized html safe to show on your pages.
|
|
*/
|
|
function tln_sanitize($body,
|
|
$tag_list,
|
|
$rm_tags_with_content,
|
|
$self_closing_tags,
|
|
$force_tag_closing,
|
|
$rm_attnames,
|
|
$bad_attvals,
|
|
$add_attr_to_tag
|
|
)
|
|
{
|
|
$me = 'tln_sanitize';
|
|
/**
|
|
* Normalize rm_tags and rm_tags_with_content.
|
|
*/
|
|
$rm_tags = array_shift($tag_list);
|
|
@array_walk($tag_list, 'tln_casenormalize');
|
|
@array_walk($rm_tags_with_content, 'tln_casenormalize');
|
|
@array_walk($self_closing_tags, 'tln_casenormalize');
|
|
/**
|
|
* See if tag_list is of tags to remove or tags to allow.
|
|
* false means remove these tags
|
|
* true means allow these tags
|
|
*/
|
|
$curpos = 0;
|
|
$open_tags = Array();
|
|
$trusted = "<!-- begin tln_sanitized html -->\n";
|
|
$skip_content = false;
|
|
/**
|
|
* Take care of netscape's stupid javascript entities like
|
|
* &{alert('boo')};
|
|
*/
|
|
$body = preg_replace('/&(\{.*?\};)/si', '&\\1', $body);
|
|
while (($curtag = tln_getnxtag($body, $curpos)) != FALSE){
|
|
list($tagname, $attary, $tagtype, $lt, $gt) = $curtag;
|
|
$free_content = substr($body, $curpos, $lt - $curpos);
|
|
if ($skip_content == false){
|
|
$trusted .= $free_content;
|
|
} else {
|
|
}
|
|
if ($tagname != FALSE){
|
|
if ($tagtype == 2){
|
|
if ($skip_content == $tagname){
|
|
/**
|
|
* Got to the end of tag we needed to remove.
|
|
*/
|
|
$tagname = false;
|
|
$skip_content = false;
|
|
} else {
|
|
if ($skip_content == false){
|
|
if (isset($open_tags{$tagname}) &&
|
|
$open_tags{$tagname} > 0){
|
|
$open_tags{$tagname}--;
|
|
} else {
|
|
$tagname = false;
|
|
}
|
|
} else {
|
|
}
|
|
}
|
|
} else {
|
|
/**
|
|
* $rm_tags_with_content
|
|
*/
|
|
if ($skip_content == false){
|
|
/**
|
|
* See if this is a self-closing type and change
|
|
* tagtype appropriately.
|
|
*/
|
|
if ($tagtype == 1
|
|
&& in_array($tagname, $self_closing_tags)){
|
|
$tagtype = 3;
|
|
}
|
|
/**
|
|
* See if we should skip this tag and any content
|
|
* inside it.
|
|
*/
|
|
if ($tagtype == 1
|
|
&& in_array($tagname, $rm_tags_with_content)){
|
|
$skip_content = $tagname;
|
|
} else {
|
|
if (($rm_tags == false
|
|
&& in_array($tagname, $tag_list)) ||
|
|
($rm_tags == true
|
|
&& !in_array($tagname, $tag_list))){
|
|
$tagname = false;
|
|
} else {
|
|
if ($tagtype == 1){
|
|
if (isset($open_tags{$tagname})){
|
|
$open_tags{$tagname}++;
|
|
} else {
|
|
$open_tags{$tagname} = 1;
|
|
}
|
|
}
|
|
/**
|
|
* This is where we run other checks.
|
|
*/
|
|
if (is_array($attary) && sizeof($attary) > 0){
|
|
$attary = tln_fixatts($tagname,
|
|
$attary,
|
|
$rm_attnames,
|
|
$bad_attvals,
|
|
$add_attr_to_tag);
|
|
}
|
|
}
|
|
}
|
|
} else {
|
|
}
|
|
}
|
|
if ($tagname != false && $skip_content == false){
|
|
$trusted .= tln_tagprint($tagname, $attary, $tagtype);
|
|
}
|
|
} else {
|
|
}
|
|
$curpos = $gt + 1;
|
|
}
|
|
$trusted .= substr($body, $curpos, strlen($body) - $curpos);
|
|
if ($force_tag_closing == true){
|
|
foreach ($open_tags as $tagname=>$opentimes){
|
|
while ($opentimes > 0){
|
|
$trusted .= '</' . $tagname . '>';
|
|
$opentimes--;
|
|
}
|
|
}
|
|
$trusted .= "\n";
|
|
}
|
|
$trusted .= "<!-- end tln_sanitized html -->\n";
|
|
return $trusted;
|
|
}
|
|
|
|
//
|
|
// Use the nifty htmlfilter library
|
|
//
|
|
|
|
|
|
function HTMLFilter($body, $trans_image_path, $block_external_images = false) {
|
|
|
|
$tag_list = Array(
|
|
false,
|
|
"object",
|
|
"meta",
|
|
"html",
|
|
"head",
|
|
"base",
|
|
"link",
|
|
"frame",
|
|
"iframe",
|
|
"plaintext",
|
|
"marquee"
|
|
);
|
|
|
|
$rm_tags_with_content = Array(
|
|
"script",
|
|
"applet",
|
|
"embed",
|
|
"title",
|
|
"frameset",
|
|
"xmp",
|
|
"xml"
|
|
);
|
|
|
|
$self_closing_tags = Array(
|
|
"img",
|
|
"br",
|
|
"hr",
|
|
"input",
|
|
"outbind"
|
|
);
|
|
|
|
$force_tag_closing = true;
|
|
|
|
$rm_attnames = Array(
|
|
"/.*/" =>
|
|
Array(
|
|
// "/target/i",
|
|
"/^on.*/i",
|
|
"/^dynsrc/i",
|
|
"/^data.*/i",
|
|
"/^lowsrc.*/i"
|
|
)
|
|
);
|
|
|
|
$bad_attvals = Array(
|
|
"/.*/" =>
|
|
Array(
|
|
"/^src|background/i" =>
|
|
Array(
|
|
Array(
|
|
"/^([\'\"])\s*\S+script\s*:.*([\'\"])/si",
|
|
"/^([\'\"])\s*mocha\s*:*.*([\'\"])/si",
|
|
"/^([\'\"])\s*about\s*:.*([\'\"])/si"
|
|
),
|
|
Array(
|
|
"\\1$trans_image_path\\2",
|
|
"\\1$trans_image_path\\2",
|
|
"\\1$trans_image_path\\2",
|
|
"\\1$trans_image_path\\2"
|
|
)
|
|
),
|
|
"/^href|action/i" =>
|
|
Array(
|
|
Array(
|
|
"/^([\'\"])\s*\S+script\s*:.*([\'\"])/si",
|
|
"/^([\'\"])\s*mocha\s*:*.*([\'\"])/si",
|
|
"/^([\'\"])\s*about\s*:.*([\'\"])/si"
|
|
),
|
|
Array(
|
|
"\\1#\\1",
|
|
"\\1#\\1",
|
|
"\\1#\\1",
|
|
"\\1#\\1"
|
|
)
|
|
),
|
|
"/^style/i" =>
|
|
Array(
|
|
Array(
|
|
"/expression/i",
|
|
"/binding/i",
|
|
"/behaviou*r/i",
|
|
"/include-source/i",
|
|
"/position\s*:\s*absolute/i",
|
|
"/url\s*\(\s*([\'\"])\s*\S+script\s*:.*([\'\"])\s*\)/si",
|
|
"/url\s*\(\s*([\'\"])\s*mocha\s*:.*([\'\"])\s*\)/si",
|
|
"/url\s*\(\s*([\'\"])\s*about\s*:.*([\'\"])\s*\)/si",
|
|
"/(.*)\s*:\s*url\s*\(\s*([\'\"]*)\s*\S+script\s*:.*([\'\"]*)\s*\)/si"
|
|
),
|
|
Array(
|
|
"idiocy",
|
|
"idiocy",
|
|
"idiocy",
|
|
"idiocy",
|
|
"",
|
|
"url(\\1#\\1)",
|
|
"url(\\1#\\1)",
|
|
"url(\\1#\\1)",
|
|
"url(\\1#\\1)",
|
|
"url(\\1#\\1)",
|
|
"\\1:url(\\2#\\3)"
|
|
)
|
|
)
|
|
)
|
|
);
|
|
|
|
if ($block_external_images){
|
|
array_push($bad_attvals{'/.*/'}{'/^src|background/i'}[0],
|
|
'/^([\'\"])\s*https*:.*([\'\"])/si');
|
|
array_push($bad_attvals{'/.*/'}{'/^src|background/i'}[1],
|
|
"\\1$trans_image_path\\1");
|
|
array_push($bad_attvals{'/.*/'}{'/^style/i'}[0],
|
|
'/url\(([\'\"])\s*https*:.*([\'\"])\)/si');
|
|
array_push($bad_attvals{'/.*/'}{'/^style/i'}[1],
|
|
"url(\\1$trans_image_path\\1)");
|
|
}
|
|
|
|
$add_attr_to_tag = Array(
|
|
"/^a$/i" =>
|
|
Array('target'=>'"_blank"')
|
|
);
|
|
|
|
$trusted = tln_sanitize($body,
|
|
$tag_list,
|
|
$rm_tags_with_content,
|
|
$self_closing_tags,
|
|
$force_tag_closing,
|
|
$rm_attnames,
|
|
$bad_attvals,
|
|
$add_attr_to_tag
|
|
);
|
|
return $trusted;
|
|
}
|
|
|
|
?>
|