mirror of
https://github.com/moodle/moodle.git
synced 2025-08-05 08:56:36 +02:00
MDL-28627 remove buggy and obsolete KSES cleaning
This commit is contained in:
Petr Skoda
parent
3a81b37617
commit
73b309e6a3
10 changed files with 9 additions and 902 deletions
158
lib/weblib.php
158
lib/weblib.php
|
|
@ -77,26 +77,6 @@ define('URL_MATCH_PARAMS', 1);
|
|||
*/
|
||||
define('URL_MATCH_EXACT', 2);
|
||||
|
||||
/**
|
||||
* Allowed tags - string of html tags that can be tested against for safe html tags
|
||||
* @global string $ALLOWED_TAGS
|
||||
* @name $ALLOWED_TAGS
|
||||
*/
|
||||
global $ALLOWED_TAGS;
|
||||
$ALLOWED_TAGS =
|
||||
'<p><br><b><i><u><font><table><tbody><thead><tfoot><span><div><tr><td><th><ol><ul><dl><li><dt><dd><h1><h2><h3><h4><h5><h6><hr><img><a><strong><emphasis><em><sup><sub><address><cite><blockquote><pre><strike><param><acronym><nolink><lang><tex><algebra><math><mi><mn><mo><mtext><mspace><ms><mrow><mfrac><msqrt><mroot><mstyle><merror><mpadded><mphantom><mfenced><msub><msup><msubsup><munder><mover><munderover><mmultiscripts><mtable><mtr><mtd><maligngroup><malignmark><maction><cn><ci><apply><reln><fn><interval><inverse><sep><condition><declare><lambda><compose><ident><quotient><exp><factorial><divide><max><min><minus><plus><power><rem><times><root><gcd><and><or><xor><not><implies><forall><exists><abs><conjugate><eq><neq><gt><lt><geq><leq><ln><log><int><diff><partialdiff><lowlimit><uplimit><bvar><degree><set><list><union><intersect><in><notin><subset><prsubset><notsubset><notprsubset><setdiff><sum><product><limit><tendsto><mean><sdev><variance><median><mode><moment><vector><matrix><matrixrow><determinant><transpose><selector><annotation><semantics><annotation-xml><tt><code>';
|
||||
|
||||
/**
|
||||
* Allowed protocols - array of protocols that are safe to use in links and so on
|
||||
* @global string $ALLOWED_PROTOCOLS
|
||||
*/
|
||||
$ALLOWED_PROTOCOLS = array('http', 'https', 'ftp', 'news', 'mailto', 'rtsp', 'teamspeak', 'gopher', 'mms',
|
||||
'color', 'callto', 'cursor', 'text-align', 'font-size', 'font-weight', 'font-style', 'font-family',
|
||||
'border', 'border-bottom', 'border-left', 'border-top', 'border-right', 'margin', 'margin-bottom', 'margin-left', 'margin-top', 'margin-right',
|
||||
'padding', 'padding-bottom', 'padding-left', 'padding-top', 'padding-right', 'vertical-align',
|
||||
'background', 'background-color', 'text-decoration'); // CSS as well to get through kses
|
||||
|
||||
|
||||
/// Functions
|
||||
|
||||
/**
|
||||
|
|
@ -1309,19 +1289,6 @@ function wikify_links($string) {
|
|||
return preg_replace('~(<a [^<]*href=["|\']?([^ "\']*)["|\']?[^>]*>([^<]*)</a>)~i','$3 [ $2 ]', $string);
|
||||
}
|
||||
|
||||
/**
|
||||
* Replaces non-standard HTML entities
|
||||
*
|
||||
* @param string $string
|
||||
* @return string
|
||||
*/
|
||||
function fix_non_standard_entities($string) {
|
||||
$text = preg_replace('/�*([0-9]+);?/', '&#$1;', $string);
|
||||
$text = preg_replace('/�*([0-9a-fA-F]+);?/', '&#x$1;', $text);
|
||||
$text = preg_replace('[\x00-\x08\x0b-\x0c\x0e-\x1f]', '', $text);
|
||||
return $text;
|
||||
}
|
||||
|
||||
/**
|
||||
* Given text in a variety of format codings, this function returns
|
||||
* the text as plain text suitable for plain email.
|
||||
|
|
@ -1436,8 +1403,6 @@ function trusttext_trusted($context) {
|
|||
/**
|
||||
* Is trusttext feature active?
|
||||
*
|
||||
* @global object
|
||||
* @param object $context
|
||||
* @return bool
|
||||
*/
|
||||
function trusttext_active() {
|
||||
|
|
@ -1459,8 +1424,6 @@ function trusttext_active() {
|
|||
* @return string The cleaned up text
|
||||
*/
|
||||
function clean_text($text, $format = FORMAT_HTML, $options = array()) {
|
||||
global $ALLOWED_TAGS, $CFG;
|
||||
|
||||
if (empty($text) or is_numeric($text)) {
|
||||
return (string)$text;
|
||||
}
|
||||
|
|
@ -1474,22 +1437,7 @@ function clean_text($text, $format = FORMAT_HTML, $options = array()) {
|
|||
return $text;
|
||||
}
|
||||
|
||||
if (!empty($CFG->enablehtmlpurifier)) {
|
||||
$text = purify_html($text, $options);
|
||||
} else {
|
||||
/// Fix non standard entity notations
|
||||
$text = fix_non_standard_entities($text);
|
||||
|
||||
/// Remove tags that are not allowed
|
||||
$text = strip_tags($text, $ALLOWED_TAGS);
|
||||
|
||||
/// Clean up embedded scripts and , using kses
|
||||
$text = cleanAttributes($text);
|
||||
|
||||
/// Again remove tags that are not allowed
|
||||
$text = strip_tags($text, $ALLOWED_TAGS);
|
||||
|
||||
}
|
||||
$text = purify_html($text, $options);
|
||||
|
||||
// Remove potential script events - some extra protection for undiscovered bugs in our code
|
||||
$text = preg_replace("~([^a-z])language([[:space:]]*)=~i", "$1Xlanguage=", $text);
|
||||
|
|
@ -1501,10 +1449,10 @@ function clean_text($text, $format = FORMAT_HTML, $options = array()) {
|
|||
/**
|
||||
* KSES replacement cleaning function - uses HTML Purifier.
|
||||
*
|
||||
* @global object
|
||||
* @param string $text The (X)HTML string to purify
|
||||
* @param array $options Array of options; currently only option supported is 'allowid' (if set,
|
||||
* does not remove id attributes when cleaning)
|
||||
* @return string
|
||||
*/
|
||||
function purify_html($text, $options = array()) {
|
||||
global $CFG;
|
||||
|
|
@ -1568,89 +1516,6 @@ function purify_html($text, $options = array()) {
|
|||
return $text;
|
||||
}
|
||||
|
||||
/**
|
||||
* This function takes a string and examines it for HTML tags.
|
||||
*
|
||||
* If tags are detected it passes the string to a helper function {@link cleanAttributes2()}
|
||||
* which checks for attributes and filters them for malicious content
|
||||
*
|
||||
* @param string $str The string to be examined for html tags
|
||||
* @return string
|
||||
*/
|
||||
function cleanAttributes($str){
|
||||
$result = preg_replace_callback(
|
||||
'%(<[^>]*(>|$)|>)%m', #search for html tags
|
||||
"cleanAttributes2",
|
||||
$str
|
||||
);
|
||||
return $result;
|
||||
}
|
||||
|
||||
/**
|
||||
* This function takes a string with an html tag and strips out any unallowed
|
||||
* protocols e.g. javascript:
|
||||
*
|
||||
* It calls ancillary functions in kses which are prefixed by kses
|
||||
*
|
||||
* @global object
|
||||
* @global string
|
||||
* @param array $htmlArray An array from {@link cleanAttributes()}, containing in its 1st
|
||||
* element the html to be cleared
|
||||
* @return string
|
||||
*/
|
||||
function cleanAttributes2($htmlArray){
|
||||
|
||||
global $CFG, $ALLOWED_PROTOCOLS;
|
||||
require_once($CFG->libdir .'/kses.php');
|
||||
|
||||
$htmlTag = $htmlArray[1];
|
||||
if (substr($htmlTag, 0, 1) != '<') {
|
||||
return '>'; //a single character ">" detected
|
||||
}
|
||||
if (!preg_match('%^<\s*(/\s*)?([a-zA-Z0-9]+)([^>]*)>?$%', $htmlTag, $matches)) {
|
||||
return ''; // It's seriously malformed
|
||||
}
|
||||
$slash = trim($matches[1]); //trailing xhtml slash
|
||||
$elem = $matches[2]; //the element name
|
||||
$attrlist = $matches[3]; // the list of attributes as a string
|
||||
|
||||
$attrArray = kses_hair($attrlist, $ALLOWED_PROTOCOLS);
|
||||
|
||||
$attStr = '';
|
||||
foreach ($attrArray as $arreach) {
|
||||
$arreach['name'] = strtolower($arreach['name']);
|
||||
if ($arreach['name'] == 'style') {
|
||||
$value = $arreach['value'];
|
||||
while (true) {
|
||||
$prevvalue = $value;
|
||||
$value = kses_no_null($value);
|
||||
$value = preg_replace("/\/\*.*\*\//Us", '', $value);
|
||||
$value = kses_decode_entities($value);
|
||||
$value = preg_replace('/(&#[0-9]+)(;?)/', "\\1;", $value);
|
||||
$value = preg_replace('/(&#x[0-9a-fA-F]+)(;?)/', "\\1;", $value);
|
||||
if ($value === $prevvalue) {
|
||||
$arreach['value'] = $value;
|
||||
break;
|
||||
}
|
||||
}
|
||||
$arreach['value'] = preg_replace("/j\s*a\s*v\s*a\s*s\s*c\s*r\s*i\s*p\s*t/i", "Xjavascript", $arreach['value']);
|
||||
$arreach['value'] = preg_replace("/v\s*b\s*s\s*c\s*r\s*i\s*p\s*t/i", "Xvbscript", $arreach['value']);
|
||||
$arreach['value'] = preg_replace("/e\s*x\s*p\s*r\s*e\s*s\s*s\s*i\s*o\s*n/i", "Xexpression", $arreach['value']);
|
||||
$arreach['value'] = preg_replace("/b\s*i\s*n\s*d\s*i\s*n\s*g/i", "Xbinding", $arreach['value']);
|
||||
} else if ($arreach['name'] == 'href') {
|
||||
//Adobe Acrobat Reader XSS protection
|
||||
$arreach['value'] = preg_replace('/(\.(pdf|fdf|xfdf|xdp|xfd)[^#]*)#.*$/i', '$1', $arreach['value']);
|
||||
}
|
||||
$attStr .= ' '.$arreach['name'].'="'.$arreach['value'].'"';
|
||||
}
|
||||
|
||||
$xhtml_slash = '';
|
||||
if (preg_match('%/\s*$%', $attrlist)) {
|
||||
$xhtml_slash = ' /';
|
||||
}
|
||||
return '<'. $slash . $elem . $attStr . $xhtml_slash .'>';
|
||||
}
|
||||
|
||||
/**
|
||||
* Given plain text, makes it into HTML as nicely as possible.
|
||||
* May contain HTML tags already
|
||||
|
|
@ -1659,7 +1524,6 @@ function cleanAttributes2($htmlArray){
|
|||
* by {@see format_text()} to convert FORMAT_MOODLE to HTML. You are supposed
|
||||
* to call format_text() in most of cases.
|
||||
*
|
||||
* @global object
|
||||
* @param string $text The string to convert.
|
||||
* @param boolean $smiley_ignored Was used to determine if smiley characters should convert to smiley images, ignored now
|
||||
* @param boolean $para If true then the returned string will be wrapped in div tags
|
||||
|
|
@ -1668,8 +1532,6 @@ function cleanAttributes2($htmlArray){
|
|||
*/
|
||||
|
||||
function text_to_html($text, $smiley_ignored=null, $para=true, $newlines=true) {
|
||||
global $CFG;
|
||||
|
||||
/// Remove any whitespace that may be between HTML tags
|
||||
$text = preg_replace("~>([[:space:]]+)<~i", "><", $text);
|
||||
|
||||
|
|
@ -2612,22 +2474,6 @@ function print_maintenance_message() {
|
|||
die;
|
||||
}
|
||||
|
||||
/**
|
||||
* Adjust the list of allowed tags based on $CFG->allowobjectembed and user roles (admin)
|
||||
*
|
||||
* @global object
|
||||
* @global string
|
||||
* @return void
|
||||
*/
|
||||
function adjust_allowed_tags() {
|
||||
|
||||
global $CFG, $ALLOWED_TAGS;
|
||||
|
||||
if (!empty($CFG->allowobjectembed)) {
|
||||
$ALLOWED_TAGS .= '<embed><object>';
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* A class for tabs, Some code to print tabs
|
||||
*
|
||||
|
|
|
|||
Loading…
Add table
Add a link
Reference in a new issue