切换导航条
此项目
正在载入...
登录
何书鹏
/
salarycalculator
·
提交
转到一个项目
GitLab
转到仪表盘
项目
活动
文件
提交
管道
0
构建
0
图表
里程碑
问题
0
合并请求
0
成员
标记
维基
派生
网络
创建新的问题
下载为
邮件补丁
差异文件
浏览文件
作者
Karson
4 years ago
提交
adb3cc080abd99a13baccbdbc403a8bd166c90a7
1 个父辈
cdd53ac3
新增安全过滤类
隐藏空白字符变更
内嵌
并排对比
正在显示
2 个修改的文件
包含
884 行增加
和
0 行删除
application/common.php
application/common/library/Security.php
application/common.php
查看文件 @
adb3cc0
...
...
@@ -408,3 +408,13 @@ if (!function_exists('check_cors_request')) {
}
}
}
if (!function_exists('xss_clean')) {
/**
* 清理XSS
*/
function xss_clean(
$content
,
$is_image
= false)
{
return \app\common\library\Security::instance()->xss_clean(
$content
,
$is_image
);
}
}
...
...
application/common/library/Security.php
0 → 100644
查看文件 @
adb3cc0
<?php
namespace
app\common\library
;
use
Exception
;
/**
* 安全过滤类
*
* @category Security
* @copyright Copyright (c) 2008 - 2014, EllisLab, Inc. (https://ellislab.com/)
* @copyright Copyright (c) 2014 - 2019, British Columbia Institute of Technology (https://bcit.ca/)
* @license https://opensource.org/licenses/MIT MIT License
* @link https://codeigniter.com
* @author EllisLab Dev Team
*/
class
Security
{
protected
static
$instance
=
null
;
/**
* List of sanitize filename strings
*
* @var array
*/
public
$filename_bad_chars
=
array
(
'../'
,
'<!--'
,
'-->'
,
'<'
,
'>'
,
"'"
,
'"'
,
'&'
,
'$'
,
'#'
,
'{'
,
'}'
,
'['
,
']'
,
'='
,
';'
,
'?'
,
'%20'
,
'%22'
,
'%3c'
,
// <
'%253c'
,
// <
'%3e'
,
// >
'%0e'
,
// >
'%28'
,
// (
'%29'
,
// )
'%2528'
,
// (
'%26'
,
// &
'%24'
,
// $
'%3f'
,
// ?
'%3b'
,
// ;
'%3d'
// =
);
/**
* Character set
*
* Will be overridden by the constructor.
*
* @var string
*/
public
$charset
=
'UTF-8'
;
/**
* XSS Hash
*
* Random Hash for protecting URLs.
*
* @var string
*/
protected
$_xss_hash
;
/**
* List of never allowed strings
*
* @var array
*/
protected
$_never_allowed_str
=
array
(
'document.cookie'
=>
'[removed]'
,
'(document).cookie'
=>
'[removed]'
,
'document.write'
=>
'[removed]'
,
'(document).write'
=>
'[removed]'
,
'.parentNode'
=>
'[removed]'
,
'.innerHTML'
=>
'[removed]'
,
'-moz-binding'
=>
'[removed]'
,
'<!--'
=>
'<!--'
,
'-->'
=>
'-->'
,
'<![CDATA['
=>
'<![CDATA['
,
'<comment>'
=>
'<comment>'
,
'<%'
=>
'<%'
);
/**
* List of never allowed regex replacements
*
* @var array
*/
protected
$_never_allowed_regex
=
array
(
'javascript\s*:'
,
'(\(?document\)?|\(?window\)?(\.document)?)\.(location|on\w*)'
,
'expression\s*(\(|&\#40;)'
,
// CSS and IE
'vbscript\s*:'
,
// IE, surprise!
'wscript\s*:'
,
// IE
'jscript\s*:'
,
// IE
'vbs\s*:'
,
// IE
'Redirect\s+30\d'
,
"([
\"
'])?data\s*:[^
\\
1]*?base64[^
\\
1]*?,[^
\\
1]*?
\\
1?"
);
protected
$options
=
[
'placeholder'
=>
'[removed]'
];
/**
* Class constructor
*
* @return void
*/
public
function
__construct
(
$options
=
[])
{
$this
->
options
=
array_merge
(
$this
->
options
,
$options
);
foreach
(
$this
->
_never_allowed_str
as
$index
=>
&
$item
)
{
$item
=
str_replace
(
'[removed]'
,
$this
->
options
[
'placeholder'
],
$item
);
}
}
/**
*
* @param array $options 参数
* @return Security
*/
public
static
function
instance
(
$options
=
[])
{
if
(
is_null
(
self
::
$instance
))
{
self
::
$instance
=
new
static
(
$options
);
}
return
self
::
$instance
;
}
/**
* XSS Clean
*
* Sanitizes data so that Cross Site Scripting Hacks can be
* prevented. This method does a fair amount of work but
* it is extremely thorough, designed to prevent even the
* most obscure XSS attempts. Nothing is ever 100% foolproof,
* of course, but I haven't been able to get anything passed
* the filter.
*
* Note: Should only be used to deal with data upon submission.
* It's not something that should be used for general
* runtime processing.
*
* @link http://channel.bitflux.ch/wiki/XSS_Prevention
* Based in part on some code and ideas from Bitflux.
*
* @link http://ha.ckers.org/xss.html
* To help develop this script I used this great list of
* vulnerabilities along with a few other hacks I've
* harvested from examining vulnerabilities in other programs.
*
* @param string|string[] $str Input data
* @param bool $is_image Whether the input is an image
* @return string
*/
public
function
xss_clean
(
$str
,
$is_image
=
false
)
{
// Is the string an array?
if
(
is_array
(
$str
))
{
foreach
(
$str
as
$key
=>
&
$value
)
{
$str
[
$key
]
=
$this
->
xss_clean
(
$value
);
}
return
$str
;
}
// Remove Invisible Characters
$str
=
$this
->
remove_invisible_characters
(
$str
);
/*
* URL Decode
*
* Just in case stuff like this is submitted:
*
* <a href="http://%77%77%77%2E%67%6F%6F%67%6C%65%2E%63%6F%6D">Google</a>
*
* Note: Use rawurldecode() so it does not remove plus signs
*/
if
(
stripos
(
$str
,
'%'
)
!==
false
)
{
do
{
$oldstr
=
$str
;
$str
=
rawurldecode
(
$str
);
$str
=
preg_replace_callback
(
'#%(?:\s*[0-9a-f]){2,}#i'
,
array
(
$this
,
'_urldecodespaces'
),
$str
);
}
while
(
$oldstr
!==
$str
);
unset
(
$oldstr
);
}
/*
* Convert character entities to ASCII
*
* This permits our tests below to work reliably.
* We only convert entities that are within tags since
* these are the ones that will pose security problems.
*/
$str
=
preg_replace_callback
(
"/[^a-z0-9>]+[a-z0-9]+=([\'
\"
]).*?
\\
1/si"
,
array
(
$this
,
'_convert_attribute'
),
$str
);
$str
=
preg_replace_callback
(
'/<\w+.*/si'
,
array
(
$this
,
'_decode_entity'
),
$str
);
// Remove Invisible Characters Again!
$str
=
$this
->
remove_invisible_characters
(
$str
);
/*
* Convert all tabs to spaces
*
* This prevents strings like this: ja vascript
* NOTE: we deal with spaces between characters later.
* NOTE: preg_replace was found to be amazingly slow here on
* large blocks of data, so we use str_replace.
*/
$str
=
str_replace
(
"
\t
"
,
' '
,
$str
);
// Capture converted string for later comparison
$converted_string
=
$str
;
// Remove Strings that are never allowed
$str
=
$this
->
_do_never_allowed
(
$str
);
/*
* Makes PHP tags safe
*
* Note: XML tags are inadvertently replaced too:
*
* <?xml
*
* But it doesn't seem to pose a problem.
*/
if
(
$is_image
===
true
)
{
// Images have a tendency to have the PHP short opening and
// closing tags every so often so we skip those and only
// do the long opening tags.
$str
=
preg_replace
(
'/<\?(php)/i'
,
'<?\\1'
,
$str
);
}
else
{
$str
=
str_replace
(
array
(
'<?'
,
'?'
.
'>'
),
array
(
'<?'
,
'?>'
),
$str
);
}
/*
* Compact any exploded words
*
* This corrects words like: j a v a s c r i p t
* These words are compacted back to their correct state.
*/
$words
=
array
(
'javascript'
,
'expression'
,
'vbscript'
,
'jscript'
,
'wscript'
,
'vbs'
,
'script'
,
'base64'
,
'applet'
,
'alert'
,
'document'
,
'write'
,
'cookie'
,
'window'
,
'confirm'
,
'prompt'
,
'eval'
);
foreach
(
$words
as
$word
)
{
$word
=
implode
(
'\s*'
,
str_split
(
$word
))
.
'\s*'
;
// We only want to do this when it is followed by a non-word character
// That way valid stuff like "dealer to" does not become "dealerto"
$str
=
preg_replace_callback
(
'#('
.
substr
(
$word
,
0
,
-
3
)
.
')(\W)#is'
,
array
(
$this
,
'_compact_exploded_words'
),
$str
);
}
/*
* Remove disallowed Javascript in links or img tags
* We used to do some version comparisons and use of stripos(),
* but it is dog slow compared to these simplified non-capturing
* preg_match(), especially if the pattern exists in the string
*
* Note: It was reported that not only space characters, but all in
* the following pattern can be parsed as separators between a tag name
* and its attributes: [\d\s"\'`;,\/\=\(\x00\x0B\x09\x0C]
* ... however, $this->remove_invisible_characters() above already strips the
* hex-encoded ones, so we'll skip them below.
*/
do
{
$original
=
$str
;
if
(
preg_match
(
'/<a/i'
,
$str
))
{
$str
=
preg_replace_callback
(
'#<a(?:rea)?[^a-z0-9>]+([^>]*?)(?:>|$)#si'
,
array
(
$this
,
'_js_link_removal'
),
$str
);
}
if
(
preg_match
(
'/<img/i'
,
$str
))
{
$str
=
preg_replace_callback
(
'#<img[^a-z0-9]+([^>]*?)(?:\s?/?>|$)#si'
,
array
(
$this
,
'_js_img_removal'
),
$str
);
}
if
(
preg_match
(
'/script|xss/i'
,
$str
))
{
$str
=
preg_replace
(
'#</*(?:script|xss).*?>#si'
,
$this
->
options
[
'placeholder'
],
$str
);
}
}
while
(
$original
!==
$str
);
unset
(
$original
);
/*
* Sanitize naughty HTML elements
*
* If a tag containing any of the words in the list
* below is found, the tag gets converted to entities.
*
* So this: <blink>
* Becomes: <blink>
*/
$pattern
=
'#'
.
'<((?<slash>/*\s*)((?<tagName>[a-z0-9]+)(?=[^a-z0-9]|$)|.+)'
// tag start and name, followed by a non-tag character
.
'[^\s\042\047a-z0-9>/=]*'
// a valid attribute character immediately after the tag would count as a separator
// optional attributes
.
'(?<attributes>(?:[\s\042\047/=]*'
// non-attribute characters, excluding > (tag close) for obvious reasons
.
'[^\s\042\047>/=]+'
// attribute characters
// optional attribute-value
.
'(?:\s*='
// attribute-value separator
.
'(?:[^\s\042\047=><`]+|\s*\042[^\042]*\042|\s*\047[^\047]*\047|\s*(?U:[^\s\042\047=><`]*))'
// single, double or non-quoted value
.
')?'
// end optional attribute-value group
.
')*)'
// end optional attributes group
.
'[^>]*)(?<closeTag>\>)?#isS'
;
// Note: It would be nice to optimize this for speed, BUT
// only matching the naughty elements here results in
// false positives and in turn - vulnerabilities!
do
{
$old_str
=
$str
;
$str
=
preg_replace_callback
(
$pattern
,
array
(
$this
,
'_sanitize_naughty_html'
),
$str
);
}
while
(
$old_str
!==
$str
);
unset
(
$old_str
);
/*
* Sanitize naughty scripting elements
*
* Similar to above, only instead of looking for
* tags it looks for PHP and JavaScript commands
* that are disallowed. Rather than removing the
* code, it simply converts the parenthesis to entities
* rendering the code un-executable.
*
* For example: eval('some code')
* Becomes: eval('some code')
*/
$str
=
preg_replace
(
'#(alert|prompt|confirm|cmd|passthru|eval|exec|expression|system|fopen|fsockopen|file|file_get_contents|readfile|unlink)(\s*)\((.*?)\)#si'
,
'\\1\\2(\\3)'
,
$str
);
// Same thing, but for "tag functions" (e.g. eval`some code`)
$str
=
preg_replace
(
'#(alert|prompt|confirm|cmd|passthru|eval|exec|expression|system|fopen|fsockopen|file|file_get_contents|readfile|unlink)(\s*)`(.*?)`#si'
,
'\\1\\2`\\3`'
,
$str
);
// Final clean up
// This adds a bit of extra precaution in case
// something got through the above filters
$str
=
$this
->
_do_never_allowed
(
$str
);
/*
* Images are Handled in a Special Way
* - Essentially, we want to know that after all of the character
* conversion is done whether any unwanted, likely XSS, code was found.
* If not, we return TRUE, as the image is clean.
* However, if the string post-conversion does not matched the
* string post-removal of XSS, then it fails, as there was unwanted XSS
* code found and removed/changed during processing.
*/
if
(
$is_image
===
true
)
{
return
(
$str
===
$converted_string
);
}
return
$str
;
}
// --------------------------------------------------------------------
/**
* XSS Hash
*
* Generates the XSS hash if needed and returns it.
*
* @return string XSS hash
*/
public
function
xss_hash
()
{
if
(
$this
->
_xss_hash
===
null
)
{
$rand
=
$this
->
get_random_bytes
(
16
);
$this
->
_xss_hash
=
(
$rand
===
false
)
?
md5
(
uniqid
(
mt_rand
(),
true
))
:
bin2hex
(
$rand
);
}
return
$this
->
_xss_hash
;
}
// --------------------------------------------------------------------
/**
* Get random bytes
*
* @param int $length Output length
* @return string
*/
public
function
get_random_bytes
(
$length
)
{
if
(
empty
(
$length
)
OR
!
ctype_digit
((
string
)
$length
))
{
return
false
;
}
if
(
function_exists
(
'random_bytes'
))
{
try
{
// The cast is required to avoid TypeError
return
random_bytes
((
int
)
$length
);
}
catch
(
Exception
$e
)
{
// If random_bytes() can't do the job, we can't either ...
// There's no point in using fallbacks.
return
false
;
}
}
// Unfortunately, none of the following PRNGs is guaranteed to exist ...
if
(
defined
(
'MCRYPT_DEV_URANDOM'
)
&&
(
$output
=
mcrypt_create_iv
(
$length
,
MCRYPT_DEV_URANDOM
))
!==
false
)
{
return
$output
;
}
if
(
is_readable
(
'/dev/urandom'
)
&&
(
$fp
=
fopen
(
'/dev/urandom'
,
'rb'
))
!==
false
)
{
// Try not to waste entropy ...
stream_set_chunk_size
(
$fp
,
$length
);
$output
=
fread
(
$fp
,
$length
);
fclose
(
$fp
);
if
(
$output
!==
false
)
{
return
$output
;
}
}
if
(
function_exists
(
'openssl_random_pseudo_bytes'
))
{
return
openssl_random_pseudo_bytes
(
$length
);
}
return
false
;
}
// --------------------------------------------------------------------
/**
* HTML Entities Decode
*
* A replacement for html_entity_decode()
*
* The reason we are not using html_entity_decode() by itself is because
* while it is not technically correct to leave out the semicolon
* at the end of an entity most browsers will still interpret the entity
* correctly. html_entity_decode() does not convert entities without
* semicolons, so we are left with our own little solution here. Bummer.
*
* @link https://secure.php.net/html-entity-decode
*
* @param string $str Input
* @param string $charset Character set
* @return string
*/
public
function
entity_decode
(
$str
,
$charset
=
null
)
{
if
(
strpos
(
$str
,
'&'
)
===
false
)
{
return
$str
;
}
static
$_entities
;
isset
(
$charset
)
OR
$charset
=
$this
->
charset
;
isset
(
$_entities
)
OR
$_entities
=
array_map
(
'strtolower'
,
get_html_translation_table
(
HTML_ENTITIES
,
ENT_COMPAT
|
ENT_HTML5
,
$charset
));
do
{
$str_compare
=
$str
;
// Decode standard entities, avoiding false positives
if
(
preg_match_all
(
'/&[a-z]{2,}(?![a-z;])/i'
,
$str
,
$matches
))
{
$replace
=
array
();
$matches
=
array_unique
(
array_map
(
'strtolower'
,
$matches
[
0
]));
foreach
(
$matches
as
&
$match
)
{
if
((
$char
=
array_search
(
$match
.
';'
,
$_entities
,
true
))
!==
false
)
{
$replace
[
$match
]
=
$char
;
}
}
$str
=
str_replace
(
array_keys
(
$replace
),
array_values
(
$replace
),
$str
);
}
// Decode numeric & UTF16 two byte entities
$str
=
html_entity_decode
(
preg_replace
(
'/(&#(?:x0*[0-9a-f]{2,5}(?![0-9a-f;])|(?:0*\d{2,4}(?![0-9;]))))/iS'
,
'$1;'
,
$str
),
ENT_COMPAT
|
ENT_HTML5
,
$charset
);
}
while
(
$str_compare
!==
$str
);
return
$str
;
}
// --------------------------------------------------------------------
/**
* Sanitize Filename
*
* @param string $str Input file name
* @param bool $relative_path Whether to preserve paths
* @return string
*/
public
function
sanitize_filename
(
$str
,
$relative_path
=
false
)
{
$bad
=
$this
->
filename_bad_chars
;
if
(
!
$relative_path
)
{
$bad
[]
=
'./'
;
$bad
[]
=
'/'
;
}
$str
=
$this
->
remove_invisible_characters
(
$str
,
false
);
do
{
$old
=
$str
;
$str
=
str_replace
(
$bad
,
''
,
$str
);
}
while
(
$old
!==
$str
);
return
stripslashes
(
$str
);
}
// ----------------------------------------------------------------
/**
* Strip Image Tags
*
* @param string $str
* @return string
*/
public
function
strip_image_tags
(
$str
)
{
return
preg_replace
(
array
(
'#<img[\s/]+.*?src\s*=\s*(["\'])([^\\1]+?)\\1.*?\>#i'
,
'#<img[\s/]+.*?src\s*=\s*?(([^\s"\'=<>`]+)).*?\>#i'
),
'\\2'
,
$str
);
}
// ----------------------------------------------------------------
/**
* URL-decode taking spaces into account
*
* @param array $matches
* @return string
*/
protected
function
_urldecodespaces
(
$matches
)
{
$input
=
$matches
[
0
];
$nospaces
=
preg_replace
(
'#\s+#'
,
''
,
$input
);
return
(
$nospaces
===
$input
)
?
$input
:
rawurldecode
(
$nospaces
);
}
// ----------------------------------------------------------------
/**
* Compact Exploded Words
*
* Callback method for xss_clean() to remove whitespace from
* things like 'j a v a s c r i p t'.
*
* @param array $matches
* @return string
*/
protected
function
_compact_exploded_words
(
$matches
)
{
return
preg_replace
(
'/\s+/s'
,
''
,
$matches
[
1
])
.
$matches
[
2
];
}
// --------------------------------------------------------------------
/**
* Sanitize Naughty HTML
*
* Callback method for xss_clean() to remove naughty HTML elements.
*
* @param array $matches
* @return string
*/
protected
function
_sanitize_naughty_html
(
$matches
)
{
static
$naughty_tags
=
array
(
'alert'
,
'area'
,
'prompt'
,
'confirm'
,
'applet'
,
'audio'
,
'basefont'
,
'base'
,
'behavior'
,
'bgsound'
,
'blink'
,
'body'
,
'embed'
,
'expression'
,
'form'
,
'frameset'
,
'frame'
,
'head'
,
'html'
,
'ilayer'
,
'iframe'
,
'input'
,
'button'
,
'select'
,
'isindex'
,
'layer'
,
'link'
,
'meta'
,
'keygen'
,
'object'
,
'plaintext'
,
'style'
,
'script'
,
'textarea'
,
'title'
,
'math'
,
'video'
,
'svg'
,
'xml'
,
'xss'
);
static
$evil_attributes
=
array
(
'on\w+'
,
'style'
,
'xmlns'
,
'formaction'
,
'form'
,
'xlink:href'
,
'FSCommand'
,
'seekSegmentTime'
);
// First, escape unclosed tags
if
(
empty
(
$matches
[
'closeTag'
]))
{
return
'<'
.
$matches
[
1
];
}
// Is the element that we caught naughty? If so, escape it
elseif
(
in_array
(
strtolower
(
$matches
[
'tagName'
]),
$naughty_tags
,
true
))
{
return
'<'
.
$matches
[
1
]
.
'>'
;
}
// For other tags, see if their attributes are "evil" and strip those
elseif
(
isset
(
$matches
[
'attributes'
]))
{
// We'll store the already filtered attributes here
$attributes
=
array
();
// Attribute-catching pattern
$attributes_pattern
=
'#'
.
'(?<name>[^\s\042\047>/=]+)'
// attribute characters
// optional attribute-value
.
'(?:\s*=(?<value>[^\s\042\047=><`]+|\s*\042[^\042]*\042|\s*\047[^\047]*\047|\s*(?U:[^\s\042\047=><`]*)))'
// attribute-value separator
.
'#i'
;
// Blacklist pattern for evil attribute names
$is_evil_pattern
=
'#^('
.
implode
(
'|'
,
$evil_attributes
)
.
')$#i'
;
// Each iteration filters a single attribute
do
{
// Strip any non-alpha characters that may precede an attribute.
// Browsers often parse these incorrectly and that has been a
// of numerous XSS issues we've had.
$matches
[
'attributes'
]
=
preg_replace
(
'#^[^a-z]+#i'
,
''
,
$matches
[
'attributes'
]);
if
(
!
preg_match
(
$attributes_pattern
,
$matches
[
'attributes'
],
$attribute
,
PREG_OFFSET_CAPTURE
))
{
// No (valid) attribute found? Discard everything else inside the tag
break
;
}
if
(
// Is it indeed an "evil" attribute?
preg_match
(
$is_evil_pattern
,
$attribute
[
'name'
][
0
])
// Or does it have an equals sign, but no value and not quoted? Strip that too!
OR
(
trim
(
$attribute
[
'value'
][
0
])
===
''
)
)
{
$attributes
[]
=
'xss=removed'
;
}
else
{
$attributes
[]
=
$attribute
[
0
][
0
];
}
$matches
[
'attributes'
]
=
substr
(
$matches
[
'attributes'
],
$attribute
[
0
][
1
]
+
strlen
(
$attribute
[
0
][
0
]));
}
while
(
$matches
[
'attributes'
]
!==
''
);
$attributes
=
empty
(
$attributes
)
?
''
:
' '
.
implode
(
' '
,
$attributes
);
return
'<'
.
$matches
[
'slash'
]
.
$matches
[
'tagName'
]
.
$attributes
.
'>'
;
}
return
$matches
[
0
];
}
// --------------------------------------------------------------------
/**
* JS Link Removal
*
* Callback method for xss_clean() to sanitize links.
*
* This limits the PCRE backtracks, making it more performance friendly
* and prevents PREG_BACKTRACK_LIMIT_ERROR from being triggered in
* PHP 5.2+ on link-heavy strings.
*
* @param array $match
* @return string
*/
protected
function
_js_link_removal
(
$match
)
{
return
str_replace
(
$match
[
1
],
preg_replace
(
'#href=.*?(?:(?:alert|prompt|confirm)(?:\(|&\#40;|`|&\#96;)|javascript:|livescript:|mocha:|charset=|window\.|\(?document\)?\.|\.cookie|<script|<xss|d\s*a\s*t\s*a\s*:)#si'
,
''
,
$this
->
_filter_attributes
(
$match
[
1
])
),
$match
[
0
]
);
}
// --------------------------------------------------------------------
/**
* JS Image Removal
*
* Callback method for xss_clean() to sanitize image tags.
*
* This limits the PCRE backtracks, making it more performance friendly
* and prevents PREG_BACKTRACK_LIMIT_ERROR from being triggered in
* PHP 5.2+ on image tag heavy strings.
*
* @param array $match
* @return string
*/
protected
function
_js_img_removal
(
$match
)
{
return
str_replace
(
$match
[
1
],
preg_replace
(
'#src=.*?(?:(?:alert|prompt|confirm|eval)(?:\(|&\#40;|`|&\#96;)|javascript:|livescript:|mocha:|charset=|window\.|\(?document\)?\.|\.cookie|<script|<xss|base64\s*,)#si'
,
''
,
$this
->
_filter_attributes
(
$match
[
1
])
),
$match
[
0
]
);
}
// --------------------------------------------------------------------
/**
* Attribute Conversion
*
* @param array $match
* @return string
*/
protected
function
_convert_attribute
(
$match
)
{
return
str_replace
(
array
(
'>'
,
'<'
,
'\\'
),
array
(
'>'
,
'<'
,
'\\\\'
),
$match
[
0
]);
}
// --------------------------------------------------------------------
/**
* Filter Attributes
*
* Filters tag attributes for consistency and safety.
*
* @param string $str
* @return string
*/
protected
function
_filter_attributes
(
$str
)
{
$out
=
''
;
if
(
preg_match_all
(
'#\s*[a-z\-]+\s*=\s*(\042|\047)([^\\1]*?)\\1#is'
,
$str
,
$matches
))
{
foreach
(
$matches
[
0
]
as
$match
)
{
$out
.=
preg_replace
(
'#/\*.*?\*/#s'
,
''
,
$match
);
}
}
return
$out
;
}
// --------------------------------------------------------------------
/**
* HTML Entity Decode Callback
*
* @param array $match
* @return string
*/
protected
function
_decode_entity
(
$match
)
{
// Protect GET variables in URLs
// 901119URL5918AMP18930PROTECT8198
$match
=
preg_replace
(
'|\&([a-z\_0-9\-]+)\=([a-z\_0-9\-/]+)|i'
,
$this
->
xss_hash
()
.
'\\1=\\2'
,
$match
[
0
]);
// Decode, then un-protect URL GET vars
return
str_replace
(
$this
->
xss_hash
(),
'&'
,
$this
->
entity_decode
(
$match
,
$this
->
charset
)
);
}
// --------------------------------------------------------------------
/**
* Do Never Allowed
*
* @param string
* @return string
*/
protected
function
_do_never_allowed
(
$str
)
{
$str
=
str_replace
(
array_keys
(
$this
->
_never_allowed_str
),
$this
->
_never_allowed_str
,
$str
);
foreach
(
$this
->
_never_allowed_regex
as
$regex
)
{
$str
=
preg_replace
(
'#'
.
$regex
.
'#is'
,
$this
->
options
[
'placeholder'
],
$str
);
}
return
$str
;
}
/**
* Remove Invisible Characters
*/
public
function
remove_invisible_characters
(
$str
,
$url_encoded
=
true
)
{
$non_displayables
=
array
();
// every control character except newline (dec 10),
// carriage return (dec 13) and horizontal tab (dec 09)
if
(
$url_encoded
)
{
$non_displayables
[]
=
'/%0[0-8bcef]/i'
;
// url encoded 00-08, 11, 12, 14, 15
$non_displayables
[]
=
'/%1[0-9a-f]/i'
;
// url encoded 16-31
$non_displayables
[]
=
'/%7f/i'
;
// url encoded 127
}
$non_displayables
[]
=
'/[\x00-\x08\x0B\x0C\x0E-\x1F\x7F]+/S'
;
// 00-08, 11, 12, 14-31, 127
do
{
$str
=
preg_replace
(
$non_displayables
,
''
,
$str
,
-
1
,
$count
);
}
while
(
$count
);
return
$str
;
}
}
...
...
请
注册
或
登录
后发表评论