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PHP各种过滤字符函数
/**
* 返回经addslashes处理过的字符串或数组
* @param $string 需要处理的字符串或数组
* @return mixed
*/
function new_addslashes($string) {
if(!is_array($string)) return addslashes($string);
foreach($string as $key => $val) $string[$key] = new_addslashes($val);
return $string;
}
?>
//对请求的字符串进行安全处理
/*
$safestep
0 为不处理,
1 为禁止不安全HTML内容(javascript等),
2 完全禁止HTML内容,并替换部份不安全字符串(如:eval(、union、CONCAT(、--、等)
*/
function StringSafe($str, $safestep=-1){
$safestep = ($safestep > -1) ? $safestep : 1;
if($safestep == 1){
$str = preg_replace("#script:#i", "script:", $str);
$str = preg_replace("#]*>#isU", '', $str);
$str = preg_replace("#[ ]{1,}#", ' ', $str);
return $str;
}else if($safestep == 2){
$str = addslashes(htmlspecialchars(stripslashes($str)));
$str = preg_replace("#eval#i", 'eval', $str);
$str = preg_replace("#union#i", 'union', $str);
$str = preg_replace("#concat#i", 'concat', $str);
$str = preg_replace("#--#", '--', $str);
$str = preg_replace("#[ ]{1,}#", ' ', $str);
return $str;
}else{
return $str;
}
}
?>
/**
+----------------------------------------------------------
* 输出安全的html,用于过滤危险代码
+----------------------------------------------------------
* @access public
+----------------------------------------------------------
* @param string $text 要处理的字符串
* @param mixed $tags 允许的标签列表,如 table|td|th|td
+----------------------------------------------------------
* @return string
+----------------------------------------------------------
*/
static public function safeHtml($text, $tags = null)
{
$text = trim($text);
//完全过滤注释
$text = preg_replace('//','',$text);
//完全过滤动态代码
$text = preg_replace('/|?'.'>/','',$text);
//完全过滤js
$text = preg_replace('/<script>/','',$text);<BR> $text = str_replace('[','[',$text);<BR> $text = str_replace(']',']',$text);<BR> $text = str_replace('|','|',$text);<BR> //过滤换行符<BR> $text = preg_replace('/ ? /','',$text);<BR> //br<BR> $text = preg_replace('/<br(s/)?'.'>/i','[br]',$text);<BR> $text = preg_replace('/([br]s*){10,}/i','[br]',$text);<BR> //过滤危险的属性,如:过滤on事件lang js<BR> while(preg_match('/(<[^><]+)(lang|on|action|background|codebase|dynsrc|lowsrc)[^><]+/i',$text,$mat)){<BR> $text=str_replace($mat[0],$mat[1],$text);<BR> }<BR> while(preg_match('/(<[^><]+)(window.|javascript:|js:|about:|file:|document.|vbs:|cookie)([^><]*)/i',$text,$mat)){<BR> $text=str_replace($mat[0],$mat[1].$mat[3],$text);<BR> }<BR> if( empty($allowTags) ) { $allowTags = self::$htmlTags['allow']; }<BR> //允许的HTML标签<BR> $text = preg_replace('/<('.$allowTags.')( [^><[]]*)>/i','[12]',$text);<BR> //过滤多余html<BR> if ( empty($banTag) ) { $banTag = self::$htmlTags['ban']; }<BR> $text = preg_replace('/</?('.$banTag.')[^><]*>/i','',$text);<BR> //过滤合法的html标签<BR> while(preg_match('/<([a-z]+)[^><[]]*>[^><]*</1>/i',$text,$mat)){<BR> $text=str_replace($mat[0],str_replace('>',']',str_replace('<','[',$mat[0])),$text);<BR> }<BR> //转换引号<BR> while(preg_match('/([[^[]]*=s*)("|')([^2=[]]+)2([^[]]*])/i',$text,$mat)){<BR> $text=str_replace($mat[0],$mat[1].'|'.$mat[3].'|'.$mat[4],$text);<BR> }<BR> //空属性转换<BR> $text = str_replace('''','||',$text);<BR> $text = str_replace('""','||',$text);<BR> //过滤错误的单个引号<BR> while(preg_match('/[[^[]]*("|')[^[]]*]/i',$text,$mat)){<BR> $text=str_replace($mat[0],str_replace($mat[1],'',$mat[0]),$text);<BR> }<BR> //转换其它所有不合法的 < ><BR> $text = str_replace('<','<',$text);<BR> $text = str_replace('>','>',$text);<BR> $text = str_replace('"','"',$text);<BR> //反转换<BR> $text = str_replace('[','<',$text);<BR> $text = str_replace(']','>',$text);<BR> $text = str_replace('|','"',$text);<BR> //过滤多余空格<BR> $text = str_replace(' ',' ',$text);<BR> return $text;<BR> }<BR> ?></script>
function RemoveXSS($val) {
// remove all non-printable characters. CR(0a) and LF(0b) and TAB(9) are allowed
// this prevents some character re-spacing such as
// note that you have to handle splits with , , and later since they *are* allowed in some // inputs
$val = preg_replace('/([x00-x08,x0b-x0c,x0e-x19])/', '', $val);
// straight replacements, the user should never need these since they're normal characters
// this prevents like
$search = 'abcdefghijklmnopqrstuvwxyz';
$search .= 'ABCDEFGHIJKLMNOPQRSTUVWXYZ';
$search .= '1234567890!@#$%^&*()';
$search .= '~`";:?+/={}[]-_|'';
for ($i = 0; $i // ;? matches the ;, which is optional
// 0{0,7} matches any padded zeros, which are optional and go up to 8 chars
// @ @ search for the hex values
$val = preg_replace('/([xX]0{0,8}'.dechex(ord($search[$i])).';?)/i', $search[$i], $val);//with a ;
// @ @ 0{0,7} matches '0' zero to seven times
$val = preg_replace('/({0,8}'.ord($search[$i]).';?)/', $search[$i], $val); // with a ;
}
// now the only remaining whitespace attacks are , , and
$ra1 = Array('javascript', 'vbscript', 'expression', 'applet', 'meta', 'xml', 'blink', 'link', 'style', 'script', 'embed', 'object', 'iframe', 'frame', 'frameset', 'ilayer', 'layer', 'bgsound', 'title', 'base');
$ra2 = Array('onabort', 'onactivate', 'onafterprint', 'onafterupdate', 'onbeforeactivate', 'onbeforecopy', 'onbeforecut', 'onbeforedeactivate', 'onbeforeeditfocus', 'onbeforepaste', 'onbeforeprint', 'onbeforeunload', 'onbeforeupdate', 'onblur', 'onbounce', 'oncellchange', 'onchange', 'onclick', 'oncontextmenu', 'oncontrolselect', 'oncopy', 'oncut', 'ondataavailable', 'ondatasetchanged', 'ondatasetcomplete', 'ondblclick', 'ondeactivate', 'ondrag', 'ondragend', 'ondragenter', 'ondragleave', 'ondragover', 'ondragstart', 'ondrop', 'onerror', 'onerrorupdate', 'onfilterchange', 'onfinish', 'onfocus', 'onfocusin', 'onfocusout', 'onhelp', 'onkeydown', 'onkeypress', 'onkeyup', 'onlayoutcomplete', 'onload', 'onlosecapture', 'onmousedown', 'onmouseenter', 'onmouseleave', 'onmousemove', 'onmouseout', 'onmouseover', 'onmouseup', 'onmousewheel', 'onmove', 'onmoveend', 'onmovestart', 'onpaste', 'onpropertychange', 'onreadystatechange', 'onreset', 'onresize', 'onresizeend', 'onresizestart', 'onrowenter', 'onrowexit', 'onrowsdelete', 'onrowsinserted', 'onscroll', 'onselect', 'onselectionchange', 'onselectstart', 'onstart', 'onstop', 'onsubmit', 'onunload');
$ra = array_merge($ra1, $ra2);
$found = true; // keep replacing as long as the previous round replaced something
while ($found == true) {
$val_before = $val;
for ($i = 0; $i $pattern = '/';
for ($j = 0; $j if ($j > 0) {
$pattern .= '(';
$pattern .= '([xX]0{0,8}([9ab]);)';
$pattern .= '|';
$pattern .= '|({0,8}([9|10|13]);)';
$pattern .= ')*';
}
$pattern .= $ra[$i][$j];
}
$pattern .= '/i';
$replacement = substr($ra[$i], 0, 2).'
$val = preg_replace($pattern, $replacement, $val); // filter out the hex tags
if ($val_before == $val) {
// no replacements were made, so exit the loop
$found = false;
}
}
}
return $val;
}
?>