最近dedecms报漏洞不断，这里分享下php的过滤函数，大牛飘过吧,给小黑阔们学习交流用

函数代码：

代码如下:

//php 批量过滤post,get敏感数据

if (get_magic_quotes_gpc()) {

$_GET = stripslashes_array($_GET);

$_POST = stripslashes_array($_POST);

}

function stripslashes_array(&$array) {

while(list($key,$var) = each($array)) {

if ($key != 'argc' && $key != 'argv' && (strtoupper($key) != $key || ''.intval($key) == "$key")) {

if (is_string($var)) {

$array[$key] = stripslashes($var);

}

if (is_array($var)) {

$array[$key] = stripslashes_array($var);

}

}

}

return $array;

}

//过滤

function htmlencode($str){

if(empty($str)) return;

if($str=="") return $str;

$str=trim($str);

$str=str_replace("&","&",$str);

$str=str_replace(">",">",$str);

$str=str_replace("<","<",$str);

$str=str_replace(chr(32)," ",$str);

$str=str_replace(chr(9)," ",$str);

$str=str_replace(chr(9)," ",$str);

$str=str_replace(chr(34),"&",$str);

$str=str_replace(chr(39),"'",$str);

$str=str_replace(chr(13),"

",$str);

$str=str_replace("'","''",$str);

$str=str_replace("select","select",$str);

$str=str_replace("SCRIPT","SCRIPT",$str);

$str=str_replace("script","script",$str);

$str=str_replace("join","join",$str);

$str=str_replace("union","union",$str);

$str=str_replace("where","where",$str);

$str=str_replace("insert","insert",$str);

$str=str_replace("delete","delete",$str);

$str=str_replace("update","update",$str);

$str=str_replace("like","like",$str);

$str=str_replace("drop","drop",$str);

$str=str_replace("create","create",$str);

$str=str_replace("modify","modify",$str);

$str=str_replace("rename","rename",$str);

$str=str_replace("alter","alter",$str);

$str=str_replace("cast","cas",$str);

return $str;

}

//解码

function htmldecode($str){

if(empty($str)) return;

if($str=="") return $str;

$str=str_replace("select","select",$str);

$str=str_replace("join","join",$str);

$str=str_replace("union","union",$str);

$str=str_replace("where","where",$str);

$str=str_replace("insert","insert",$str);

$str=str_replace("delete","delete",$str);

$str=str_replace("update","update",$str);

$str=str_replace("like","like",$str);

$str=str_replace("drop","drop",$str);

$str=str_replace("create","create",$str);

$str=str_replace("modify","modify",$str);

$str=str_replace("rename","rename",$str);

$str=str_replace("alter","alter",$str);

$str=str_replace("cas","cast",$str);

$str=str_replace("&","&",$str);

$str=str_replace(">",">",$str);

$str=str_replace("<","<",$str);

$str=str_replace(" ",chr(32),$str);

$str=str_replace(" ",chr(9),$str);

$str=str_replace(" ",chr(9),$str);

$str=str_replace("&",chr(34),$str);

$str=str_replace("'",chr(39),$str);

$str=str_replace("

",chr(13),$str);

$str=str_replace("''","'",$str);

return $str;

}

// 函数：string_filter($string, $match_type=1)

// 功能：过滤非法内容

// 参数：

// $string 需要检查的字符串

// $match_type 匹配类型,1为精确匹配, 2为模糊匹配，默认为1

//

// 返回：有非法内容返回True，无非法内容返回False

// 其他：非法关键字列表保存在txt文件里, 分为普通非法关键字和严重非法关键字两个列表

// 作者：heiyeluren

// 时间：2006-1-18

//

//======================================================================

function lib_lawless_string_filter($string, $match_type=1)

{

//字符串空直接返回为非法

$string = trim($string);

if (empty($string))

{

return false;

}

//获取重要关键字列表和普通关键字列表

$common_file = "common_list.txt"; //通用过滤关键字列表

$signify_file = "signify_list.txt"; //重要过滤关键字列表

//如果任何列表文件不存在直接返回false，否则把两个文件列表读取到两个数组里

if (!file_exists($common_file) || !file_exists($signify_file))

{

return false;

}

$common_list = file($common_file);

$signify_list = file($signify_file);

//精确匹配

if ($match_type == 1)

{

$is_lawless = exact_match($string, $common_list);

}

//模糊匹配

if ($match_type == 2)

{

$is_lawless = blur_match($string, $common_list, $signify_list);

}

//判断检索结果数组中是否有数据，如果有，证明是非法的

if (is_array($is_lawless) && !empty($is_lawless))

{

return true;

}

else

{

return false;

}

}

//---------------------

// 精确匹配,为过滤服务

//---------------------

function exact_match($string, $common_list)

{

$string = trim($string);

$string = lib_replace_end_tag($string);

//检索普通过滤关键字列表

foreach($common_list as $block)

{

$block = trim($block);

if (preg_match("/^$string$/i", $block))

{

$blist[] = $block;

}

}

//判断有没有过滤内容在数组里

if (!empty($blist))

{

return array_unique($blist);

}

return false;

}

//----------------------

// 模糊匹配,为过滤服务

//----------------------

function blur_match($string, $common_list, $signify_list)

{

$string = trim($string);

$s_len = strlen($string);

$string = lib_replace_end_tag($string);

//检索普通过滤关键字列表

foreach($common_list as $block)

{

$block = trim($block);

if (preg_match("/^$string$/i", $block))

{

$blist[] = $block;

}

}

//检索严重过滤关键字列表

foreach($signify_list as $block)

{

$block = trim($block);

if ($s_len>=strlen($block) && preg_match("/$block/i", $string))

{

$blist[] = $block;

}

}

//判断有没有过滤内容在数组里

if (!empty($blist))

{

return array_unique($blist);

}

return false;

}

//--------------------------

// 替换HTML尾标签,为过滤服务

//--------------------------

function lib_replace_end_tag($str)

{

if (empty($str)) return false;

$str = htmlspecialchars($str);

$str = str_replace( '/', "", $str);

$str = str_replace("", "", $str);

$str = str_replace(">", "", $str);

$str = str_replace("<", "", $str);

$str = str_replace("", "", $str);

$str = str_replace("", "", $str);

$str=str_replace("select","select",$str);

$str=str_replace("join","join",$str);

$str=str_replace("union","union",$str);

$str=str_replace("where","where",$str);

$str=str_replace("insert","insert",$str);

$str=str_replace("delete","delete",$str);

$str=str_replace("update","update",$str);

$str=str_replace("like","like",$str);

$str=str_replace("drop","drop",$str);

$str=str_replace("create","create",$str);

$str=str_replace("modify","modify",$str);

$str=str_replace("rename","rename",$str);

$str=str_replace("alter","alter",$str);

$str=str_replace("cas","cast",$str);

$str=str_replace("&","&",$str);

$str=str_replace(">",">",$str);

$str=str_replace("<","<",$str);

$str=str_replace(" ",chr(32),$str);

$str=str_replace(" ",chr(9),$str);

$str=str_replace(" ",chr(9),$str);

$str=str_replace("&",chr(34),$str);

$str=str_replace("'",chr(39),$str);

$str=str_replace("

",chr(13),$str);

$str=str_replace("''","'",$str);

$str=str_replace("css","'",$str);

$str=str_replace("CSS","'",$str);

return $str;

//HTML标签，可以作为扩展过滤

/*

$tags = array("/html", "/head", "/body", "/div", "/span", "/DOCTYPE", "/title", "/link", "/meta", "/style", "/p", "/h1,", "/h2,", "/h3,", "/h4,", "/h5,", "/h6", "/strong", "/em", "/abbr", "/acronym", "/address", "/bdo", "/blockquote", "/cite", "/q", "/code", "/ins", "/del", "/dfn", "/kbd", "/pre", "/samp", "/var", "/br", "/a", "/img", "/area", "/map", "/object", "/param", "/ul", "/ol", "/li", "/dl", "/dt", "/dd", "/table", "/tr", "/td", "/th", "/tbody", "/thead", "/tfoot", "/col", "/colgroup", "/caption", "/form", "/input", "/textarea", "/select", "/option", "/optgroup", "/button", "/label", "/fieldset", "/legend", "/script", "/noscript", "/b", "/i", "/tt", "/sub", "/sup", "/big", "/small", "/hr" );

*/

}

代码：

引用是直接这样：

代码如下:

$xxx = htmlspecialchars($_POST['xxx']);

或者

代码如下:

$xxx = htmlspecialchars($_GET['xxx']);

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