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A simple method to implement sql anti-injection in php, phpsql anti-injection_PHP tutorial
A simple method to implement sql anti-injection in php, phpsql anti-injection_PHP tutorial
Jul 12, 2016 am 08:53 AM
php simple method to implement sql anti-injection, phpsql anti-injection
This article describes the simple method of php to implement sql anti-injection. Share it with everyone for your reference, the details are as follows:
There is not much filtering here, mainly for the combination of php and mysql.
For general injection prevention, just use PHP’s addslashes function.
The following is a copied code:
PHP code:
$_POST = sql_injection($_POST);
$_GET = sql_injection($_GET);
function sql_injection($content)
{
if (!get_magic_quotes_gpc()) {
if (is_array($content)) {
foreach ($content as $key=>$value) {
$content[$key] = addslashes($value);
}
} else {
addslashes($content);
}
}
return $content;
}
If you want to build a system, you can use the following code, which is also copied.
PHP code:
function inject_check($sql_str) {
return eregi('select|insert|update|delete|\'|\/\*|\*|\.\.\/|\.\/|union|into|load_file|outfile', $sql_str); // 進(jìn)行過濾
}
function verify_id($id=null) {
if (!$id) { exit('沒有提交參數(shù)！'); } // 是否為空判斷
elseif (inject_check($id)) { exit('提交的參數(shù)非法！'); } // 注射判斷
elseif (!is_numeric($id)) { exit('提交的參數(shù)非法！'); } // 數(shù)字判斷
$id = intval($id); // 整型化
return $id;
}
function str_check( $str ) {
if (!get_magic_quotes_gpc()) { // 判斷magic_quotes_gpc是否打開
$str = addslashes($str); // 進(jìn)行過濾
}
$str = str_replace("_", "\_", $str); // 把 '_'過濾掉
$str = str_replace("%", "\%", $str); // 把 '%'過濾掉
return $str;
}
function post_check($post) {
if (!get_magic_quotes_gpc()) { // 判斷magic_quotes_gpc是否為打開
$post = addslashes($post); // 進(jìn)行magic_quotes_gpc沒有打開的情況對提交數(shù)據(jù)的過濾
}
$post = str_replace("_", "\_", $post); // 把 '_'過濾掉
$post = str_replace("%", "\%", $post); // 把 '%'過濾掉
$post = nl2br($post); // 回車轉(zhuǎn)換
$post = htmlspecialchars($post); // html標(biāo)記轉(zhuǎn)換
return $post;
}
Readers who are interested in more PHP related content can check out the special topics of this site: "php programming security tutorial", "php security filtering skills summary", PHP operations and operator usage summary", PHP network programming skills Summary", "Introduction Tutorial on PHP Basic Syntax", "Summary of PHP Office Document Operation Skills (Including Word, Excel, Access, PPT)", "Introduction Tutorial on PHP Object-Oriented Programming", "Summary of PHP String Usage" , "Introduction Tutorial on PHP MySQL Database Operation" and "Summary of Common PHP Database Operation Skills"
I hope this article will be helpful to everyone in PHP programming.
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