112 lines
3.5 KiB
PHP
112 lines
3.5 KiB
PHP
|
<?php
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Class that handles operations involving percent-encoding in URIs.
|
||
|
|
*
|
||
|
|
* @warning
|
||
|
|
* Be careful when reusing instances of PercentEncoder. The object
|
||
|
|
* you use for normalize() SHOULD NOT be used for encode(), or
|
||
|
|
* vice-versa.
|
||
|
|
*/
|
||
|
|
class HTMLPurifier_PercentEncoder
|
||
|
|
{
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Reserved characters to preserve when using encode().
|
||
|
|
* @type array
|
||
|
|
*/
|
||
|
|
protected $preserve = array();
|
||
|
|
|
||
|
|
/**
|
||
|
|
* String of characters that should be preserved while using encode().
|
||
|
|
* @param bool $preserve
|
||
|
|
*/
|
||
|
|
public function __construct($preserve = false)
|
||
|
|
{
|
||
|
|
// unreserved letters, ought to const-ify
|
||
|
|
for ($i = 48; $i <= 57; $i++) { // digits
|
||
|
|
$this->preserve[$i] = true;
|
||
|
|
}
|
||
|
|
for ($i = 65; $i <= 90; $i++) { // upper-case
|
||
|
|
$this->preserve[$i] = true;
|
||
|
|
}
|
||
|
|
for ($i = 97; $i <= 122; $i++) { // lower-case
|
||
|
|
$this->preserve[$i] = true;
|
||
|
|
}
|
||
|
|
$this->preserve[45] = true; // Dash -
|
||
|
|
$this->preserve[46] = true; // Period .
|
||
|
|
$this->preserve[95] = true; // Underscore _
|
||
|
|
$this->preserve[126]= true; // Tilde ~
|
||
|
|
|
||
|
|
// extra letters not to escape
|
||
|
|
if ($preserve !== false) {
|
||
|
|
for ($i = 0, $c = strlen($preserve); $i < $c; $i++) {
|
||
|
|
$this->preserve[ord($preserve[$i])] = true;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Our replacement for urlencode, it encodes all non-reserved characters,
|
||
|
|
* as well as any extra characters that were instructed to be preserved.
|
||
|
|
* @note
|
||
|
|
* Assumes that the string has already been normalized, making any
|
||
|
|
* and all percent escape sequences valid. Percents will not be
|
||
|
|
* re-escaped, regardless of their status in $preserve
|
||
|
|
* @param string $string String to be encoded
|
||
|
|
* @return string Encoded string.
|
||
|
|
*/
|
||
|
|
public function encode($string)
|
||
|
|
{
|
||
|
|
$ret = '';
|
||
|
|
for ($i = 0, $c = strlen($string); $i < $c; $i++) {
|
||
|
|
if ($string[$i] !== '%' && !isset($this->preserve[$int = ord($string[$i])])) {
|
||
|
|
$ret .= '%' . sprintf('%02X', $int);
|
||
|
|
} else {
|
||
|
|
$ret .= $string[$i];
|
||
|
|
}
|
||
|
|
}
|
||
|
|
return $ret;
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Fix up percent-encoding by decoding unreserved characters and normalizing.
|
||
|
|
* @warning This function is affected by $preserve, even though the
|
||
|
|
* usual desired behavior is for this not to preserve those
|
||
|
|
* characters. Be careful when reusing instances of PercentEncoder!
|
||
|
|
* @param string $string String to normalize
|
||
|
|
* @return string
|
||
|
|
*/
|
||
|
|
public function normalize($string)
|
||
|
|
{
|
||
|
|
if ($string == '') {
|
||
|
|
return '';
|
||
|
|
}
|
||
|
|
$parts = explode('%', $string);
|
||
|
|
$ret = array_shift($parts);
|
||
|
|
foreach ($parts as $part) {
|
||
|
|
$length = strlen($part);
|
||
|
|
if ($length < 2) {
|
||
|
|
$ret .= '%25' . $part;
|
||
|
|
continue;
|
||
|
|
}
|
||
|
|
$encoding = substr($part, 0, 2);
|
||
|
|
$text = substr($part, 2);
|
||
|
|
if (!ctype_xdigit($encoding)) {
|
||
|
|
$ret .= '%25' . $part;
|
||
|
|
continue;
|
||
|
|
}
|
||
|
|
$int = hexdec($encoding);
|
||
|
|
if (isset($this->preserve[$int])) {
|
||
|
|
$ret .= chr($int) . $text;
|
||
|
|
continue;
|
||
|
|
}
|
||
|
|
$encoding = strtoupper($encoding);
|
||
|
|
$ret .= '%' . $encoding . $text;
|
||
|
|
}
|
||
|
|
return $ret;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
// vim: et sw=4 sts=4
|