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MDL-22537 new html purifier backported to stable, unfortunately PHP5 only

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This commit is contained in:
Petr Skoda
2010-05-21 11:39:22 +00:00
parent f8502768a2
commit db359e6369
330 changed files with 13929 additions and 10060 deletions
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lib/htmlpurifier/HTMLPurifier/Encoder.php
+67 -108
View File
@@ -1,86 +1,36 @@
<?php
HTMLPurifier_ConfigSchema::define(
'Core', 'Encoding', 'utf-8', 'istring',
'If for some reason you are unable to convert all webpages to UTF-8, '.
'you can use this directive as a stop-gap compatibility change to '.
'let HTML Purifier deal with non UTF-8 input. This technique has '.
'notable deficiencies: absolutely no characters outside of the selected '.
'character encoding will be preserved, not even the ones that have '.
'been ampersand escaped (this is due to a UTF-8 specific <em>feature</em> '.
'that automatically resolves all entities), making it pretty useless '.
'for anything except the most I18N-blind applications, although '.
'%Core.EscapeNonASCIICharacters offers fixes this trouble with '.
'another tradeoff. This directive '.
'only accepts ISO-8859-1 if iconv is not enabled.'
);
HTMLPurifier_ConfigSchema::define(
'Core', 'EscapeNonASCIICharacters', false, 'bool',
'This directive overcomes a deficiency in %Core.Encoding by blindly '.
'converting all non-ASCII characters into decimal numeric entities before '.
'converting it to its native encoding. This means that even '.
'characters that can be expressed in the non-UTF-8 encoding will '.
'be entity-ized, which can be a real downer for encodings like Big5. '.
'It also assumes that the ASCII repetoire is available, although '.
'this is the case for almost all encodings. Anyway, use UTF-8! This '.
'directive has been available since 1.4.0.'
);
if ( !function_exists('iconv') ) {
// only encodings with native PHP support
HTMLPurifier_ConfigSchema::defineAllowedValues(
'Core', 'Encoding', array(
'utf-8',
'iso-8859-1'
)
);
HTMLPurifier_ConfigSchema::defineValueAliases(
'Core', 'Encoding', array(
'iso8859-1' => 'iso-8859-1'
)
);
}
HTMLPurifier_ConfigSchema::define(
'Test', 'ForceNoIconv', false, 'bool',
'When set to true, HTMLPurifier_Encoder will act as if iconv does not '.
'exist and use only pure PHP implementations.'
);
/**
* A UTF-8 specific character encoder that handles cleaning and transforming.
* @note All functions in this class should be static.
*/
class HTMLPurifier_Encoder
{
/**
* Constructor throws fatal error if you attempt to instantiate class
*/
function HTMLPurifier_Encoder() {
private function __construct() {
trigger_error('Cannot instantiate encoder, call methods statically', E_USER_ERROR);
}
/**
* Error-handler that mutes errors, alternative to shut-up operator.
*/
function muteErrorHandler() {}
/**
public static function muteErrorHandler() {}
/**
* Cleans a UTF-8 string for well-formedness and SGML validity
*
*
* It will parse according to UTF-8 and return a valid UTF8 string, with
* non-SGML codepoints excluded.
*
* @static
*
* @note Just for reference, the non-SGML code points are 0 to 31 and
* 127 to 159, inclusive. However, we allow code points 9, 10
* and 13, which are the tab, line feed and carriage return
* respectively. 128 and above the code points map to multibyte
* UTF-8 representations.
*
*
* @note Fallback code adapted from utf8ToUnicode by Henri Sivonen and
* [email protected] at <http://iki.fi/hsivonen/php-utf8/> under the
* LGPL license. Notes on what changed are inside, but in general,
@@ -94,8 +44,8 @@ class HTMLPurifier_Encoder
* would need that, and I'm probably not going to implement them.
* Once again, PHP 6 should solve all our problems.
*/
function cleanUTF8($str, $force_php = false) {
public static function cleanUTF8($str, $force_php = false) {
// UTF-8 validity is checked since PHP 4.3.5
// This is an optimization: if the string is already valid UTF-8, no
// need to do PHP stuff. 99% of the time, this will be the case.
@@ -104,31 +54,31 @@ class HTMLPurifier_Encoder
if (preg_match('/^[\x{9}\x{A}\x{D}\x{20}-\x{7E}\x{A0}-\x{D7FF}\x{E000}-\x{FFFD}\x{10000}-\x{10FFFF}]*$/Du', $str)) {
return $str;
}
$mState = 0; // cached expected number of octets after the current octet
// until the beginning of the next UTF8 character sequence
$mUcs4 = 0; // cached Unicode character
$mBytes = 1; // cached expected number of octets in the current sequence
// original code involved an $out that was an array of Unicode
// codepoints. Instead of having to convert back into UTF-8, we've
// decided to directly append valid UTF-8 characters onto a string
// $out once they're done. $char accumulates raw bytes, while $mUcs4
// turns into the Unicode code point, so there's some redundancy.
$out = '';
$char = '';
$len = strlen($str);
for($i = 0; $i < $len; $i++) {
$in = ord($str{$i});
$char .= $str[$i]; // append byte to char
if (0 == $mState) {
// When mState is zero we expect either a US-ASCII character
// When mState is zero we expect either a US-ASCII character
// or a multi-octet sequence.
if (0 == (0x80 & ($in))) {
// US-ASCII, pass straight through.
if (($in <= 31 || $in == 127) &&
if (($in <= 31 || $in == 127) &&
!($in == 9 || $in == 13 || $in == 10) // save \r\t\n
) {
// control characters, remove
@@ -158,12 +108,12 @@ class HTMLPurifier_Encoder
$mBytes = 4;
} elseif (0xF8 == (0xFC & ($in))) {
// First octet of 5 octet sequence.
//
// This is illegal because the encoded codepoint must be
//
// This is illegal because the encoded codepoint must be
// either:
// (a) not the shortest form or
// (b) outside the Unicode range of 0-0x10FFFF.
// Rather than trying to resynchronize, we will carry on
// Rather than trying to resynchronize, we will carry on
// until the end of the sequence and let the later error
// handling code catch it.
$mUcs4 = ($in);
@@ -178,7 +128,7 @@ class HTMLPurifier_Encoder
$mState = 5;
$mBytes = 6;
} else {
// Current octet is neither in the US-ASCII range nor a
// Current octet is neither in the US-ASCII range nor a
// legal first octet of a multi-octet sequence.
$mState = 0;
$mUcs4 = 0;
@@ -194,13 +144,13 @@ class HTMLPurifier_Encoder
$tmp = $in;
$tmp = ($tmp & 0x0000003F) << $shift;
$mUcs4 |= $tmp;
if (0 == --$mState) {
// End of the multi-octet sequence. mUcs4 now contains
// the final Unicode codepoint to be output
// Check for illegal sequences and codepoints.
// From Unicode 3.1, non-shortest form is illegal
if (((2 == $mBytes) && ($mUcs4 < 0x0080)) ||
((3 == $mBytes) && ($mUcs4 < 0x0800)) ||
@@ -211,7 +161,7 @@ class HTMLPurifier_Encoder
// Codepoints outside the Unicode range are illegal
($mUcs4 > 0x10FFFF)
) {
} elseif (0xFEFF != $mUcs4 && // omit BOM
// check for valid Char unicode codepoints
(
@@ -246,10 +196,9 @@ class HTMLPurifier_Encoder
}
return $out;
}
/**
* Translates a Unicode codepoint into its corresponding UTF-8 character.
* @static
* @note Based on Feyd's function at
* <http://forums.devnetwork.net/viewtopic.php?p=191404#191404>,
* which is in public domain.
@@ -260,7 +209,7 @@ class HTMLPurifier_Encoder
* maintenance/generate-entity-file.php (although this is superior,
* due to its sanity checks).
*/
// +----------+----------+----------+----------+
// | 33222222 | 22221111 | 111111 | |
// | 10987654 | 32109876 | 54321098 | 76543210 | bit
@@ -272,17 +221,17 @@ class HTMLPurifier_Encoder
// +----------+----------+----------+----------+
// | 00000000 | 00011111 | 11111111 | 11111111 | Theoretical upper limit of legal scalars: 2097151 (0x001FFFFF)
// | 00000000 | 00010000 | 11111111 | 11111111 | Defined upper limit of legal scalar codes
// +----------+----------+----------+----------+
function unichr($code) {
// +----------+----------+----------+----------+
public static function unichr($code) {
if($code > 1114111 or $code < 0 or
($code >= 55296 and $code <= 57343) ) {
// bits are set outside the "valid" range as defined
// by UNICODE 4.1.0
// by UNICODE 4.1.0
return '';
}
$x = $y = $z = $w = 0;
$x = $y = $z = $w = 0;
if ($code < 128) {
// regular ASCII character
$x = $code;
@@ -299,30 +248,35 @@ class HTMLPurifier_Encoder
$z = (($code >> 12) & 63) | 128;
$w = (($code >> 18) & 7) | 240;
}
}
}
}
// set up the actual character
$ret = '';
if($w) $ret .= chr($w);
if($z) $ret .= chr($z);
if($y) $ret .= chr($y);
$ret .= chr($x);
$ret .= chr($x);
return $ret;
}
/**
* Converts a string to UTF-8 based on configuration.
* @static
*/
function convertToUTF8($str, $config, &$context) {
$encoding = $config->get('Core', 'Encoding');
public static function convertToUTF8($str, $config, $context) {
$encoding = $config->get('Core.Encoding');
if ($encoding === 'utf-8') return $str;
static $iconv = null;
if ($iconv === null) $iconv = function_exists('iconv');
set_error_handler(array('HTMLPurifier_Encoder', 'muteErrorHandler'));
if ($iconv && !$config->get('Test', 'ForceNoIconv')) {
if ($iconv && !$config->get('Test.ForceNoIconv')) {
$str = iconv($encoding, 'utf-8//IGNORE', $str);
if ($str === false) {
// $encoding is not a valid encoding
restore_error_handler();
trigger_error('Invalid encoding ' . $encoding, E_USER_ERROR);
return '';
}
// If the string is bjorked by Shift_JIS or a similar encoding
// that doesn't support all of ASCII, convert the naughty
// characters to their true byte-wise ASCII/UTF-8 equivalents.
@@ -334,25 +288,24 @@ class HTMLPurifier_Encoder
restore_error_handler();
return $str;
}
trigger_error('Encoding not supported', E_USER_ERROR);
trigger_error('Encoding not supported, please install iconv', E_USER_ERROR);
}
/**
* Converts a string from UTF-8 based on configuration.
* @static
* @note Currently, this is a lossy conversion, with unexpressable
* characters being omitted.
*/
function convertFromUTF8($str, $config, &$context) {
$encoding = $config->get('Core', 'Encoding');
public static function convertFromUTF8($str, $config, $context) {
$encoding = $config->get('Core.Encoding');
if ($encoding === 'utf-8') return $str;
static $iconv = null;
if ($iconv === null) $iconv = function_exists('iconv');
if ($escape = $config->get('Core', 'EscapeNonASCIICharacters')) {
if ($escape = $config->get('Core.EscapeNonASCIICharacters')) {
$str = HTMLPurifier_Encoder::convertToASCIIDumbLossless($str);
}
set_error_handler(array('HTMLPurifier_Encoder', 'muteErrorHandler'));
if ($iconv && !$config->get('Test', 'ForceNoIconv')) {
if ($iconv && !$config->get('Test.ForceNoIconv')) {
// Undo our previous fix in convertToUTF8, otherwise iconv will barf
$ascii_fix = HTMLPurifier_Encoder::testEncodingSupportsASCII($encoding);
if (!$escape && !empty($ascii_fix)) {
@@ -372,10 +325,9 @@ class HTMLPurifier_Encoder
}
trigger_error('Encoding not supported', E_USER_ERROR);
}
/**
* Lossless (character-wise) conversion of HTML to ASCII
* @static
* @param $str UTF-8 string to be converted to ASCII
* @returns ASCII encoded string with non-ASCII character entity-ized
* @warning Adapted from MediaWiki, claiming fair use: this is a common
@@ -390,7 +342,7 @@ class HTMLPurifier_Encoder
* @note Sort of with cleanUTF8() but it assumes that $str is
* well-formed UTF-8
*/
function convertToASCIIDumbLossless($str) {
public static function convertToASCIIDumbLossless($str) {
$bytesleft = 0;
$result = '';
$working = 0;
@@ -420,19 +372,19 @@ class HTMLPurifier_Encoder
}
return $result;
}
/**
* This expensive function tests whether or not a given character
* encoding supports ASCII. 7/8-bit encodings like Shift_JIS will
* fail this test, and require special processing. Variable width
* encodings shouldn't ever fail.
*
*
* @param string $encoding Encoding name to test, as per iconv format
* @param bool $bypass Whether or not to bypass the precompiled arrays.
* @return Array of UTF-8 characters to their corresponding ASCII,
* which can be used to "undo" any overzealous iconv action.
*/
function testEncodingSupportsASCII($encoding, $bypass = false) {
public static function testEncodingSupportsASCII($encoding, $bypass = false) {
static $encodings = array();
if (!$bypass) {
if (isset($encodings[$encoding])) return $encodings[$encoding];
@@ -449,8 +401,14 @@ class HTMLPurifier_Encoder
set_error_handler(array('HTMLPurifier_Encoder', 'muteErrorHandler'));
if (iconv('UTF-8', $encoding, 'a') === false) return false;
for ($i = 0x20; $i <= 0x7E; $i++) { // all printable ASCII chars
$c = chr($i);
if (iconv('UTF-8', "$encoding//IGNORE", $c) === '') {
$c = chr($i); // UTF-8 char
$r = iconv('UTF-8', "$encoding//IGNORE", $c); // initial conversion
if (
$r === '' ||
// This line is needed for iconv implementations that do not
// omit characters that do not exist in the target character set
($r === $c && iconv($encoding, 'UTF-8//IGNORE', $r) !== $c)
) {
// Reverse engineer: what's the UTF-8 equiv of this byte
// sequence? This assumes that there's no variable width
// encoding that doesn't support ASCII.
@@ -461,7 +419,8 @@ class HTMLPurifier_Encoder
$encodings[$encoding] = $ret;
return $ret;
}
}
// vim: et sw=4 sts=4